AeroElectric-Archive.digest.vol-jl
April 05, 2010 - April 21, 2010
you're pondering, then there are dozens of folks here
on the List that would be pleased to see it including
yours truly.
In the mean time my best recommendations are to (1) modify
the alternator for external regulation and OV control
like B&C, (3) modify for external control of field power
including OV control like Plane Power, or (3) use Z-24.
Bob . . .
________________________________________________________________________________
| From: | Danny <dan42101(at)yahoo.com> |
| Subject: | Re: Jhp 520 PTT cable |
Bob,
Below is the reply from the good folks at Sam's photofacts...- I also sen
t an email to Rexon.- I won't hold my breath for that reply.-
-
I guess this radio will be on ebay shortly.
Thanks to all.
- DjD
Sorry, we cannot locate anything on this.
-
-
----
Jeff Morris
-
SAMS Technical Publishing, LLC
9850 East 30th Street
Indianapolis, IN 46229
-
Phone: 1-800-428-7267
Fax: 1-800-552-3910
Email: customercare1(at)samswebsite.com
--- On Thu, 4/1/10, Robert L. Nuckolls, III
wrote:
From: Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com>
Subject: Re: AeroElectric-List: Re: Jhp 520 PTT cable
Date: Thursday, April 1, 2010, 4:05 PM
s.bob(at)aeroelectric.com>
At 02:08 PM 4/1/2010, you wrote:
> Thanks,
> I borrowed a David Clark c 10-15 PTT switch.- I moved the wires in the
one jack I could get open every way I could think of.- No help.
>
> I wonder if I could cut the wire to the internal mike on the radio, and j
ust use it with the headset only and no remote PTT.
- I'm not sure the JHP-500 series radios will accept
- external PTT. My cord only carries mic audio from
- the headset to the radio. I use the hand-held's
- built in PTT to transmit.- If one can track down
- a service manual with a schematic of the radio,
- we could easily figure out what it takes.
- Bob . . .
le, List Admin.
=0A=0A=0A
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: External vr runaway "B" alternator protection |
Seems I didn't answer your questions specifically.
My apologies and thanks to a couple of List readers
that rattled my cage . . .
>
>Question: is the above correct, at least in some cases?
Have no way to know without detailed data on
the specific alternator/regulator being
considered.
> Is there an issue in an external type B regulator that a failure
> "inside the box" can result in a runaway alternator, and that
> simply pulling off power to the vr will not de-energize the alternator?
Matters not whether B-type or A-type. There
are components that can fail in a manner that
full-fields the alternator and produces a
current limited but not very voltage limited
runaway event.
> what happens if I simply pull the 60 amp B lead breaker while the
> alternator is running away?
The alternator b-lead terminal in a runaway
condition can reach well over 100 volts DC
and sustain it for some time before the field
coil smokes. The b-lead breaker is generally
designed for operation in systems not exceeding
32vdc. It's quite likely that by the time you
sense that an ov event is in progress and
react by pulling the breaker, the alternator will
be in a current limited attempt to pull the bus
up against the battery's limited ability to
hold it down.
Opening the breaker is guaranteed to start a
fire between contacts designed to break much
lower voltages. Once the arc starts, it would
liberate several thousand watts of concentrated
energy within the confines of the plastic breaker
housing.
> should I have a pullable breaker between the vr and the Field
> terminal on the alternator, that can be manually switched off?
An OV event is one of those things we always
managed with a millisecond-fast protection
system. This is not a duty you want to
take on as pilot.
is this the best way to assume control in the unlikely event of a
failure to short in the vr switching diode?
Whether it's a bad "vr switching diode" or any other component
of the alternator voltage control system, the legacy technique
calls for fast, automatic OV management techniques.
Bob . . .
________________________________________________________________________________
| From: | "Bill Hibbing" <n744bh(at)bellsouth.net> |
Just thought that I'd pass along that I'm slowly changing over to glass
so I have the following operable avionics for sale. I don't want to use
the forum for advertising so if you have any interest in any of the
items please email me direct and I' send you the price.
1. King KT-76A transponder wired for and including an Ameriking AK-350
altitude encoder.
2. STec ST-901 GPSS converter for STec A/P's.
3. 52D54 Autopilot directional gyro
4. JP instruments EDM-700 engine data monitor with new EGT and CHT
probes and STC paperwork for TC airplanes.
Bill Hibbing
Glasair
________________________________________________________________________________
| Subject: | Wanted - Used CDI |
If anyone has a GARMIN GI-106 CDI, they'd like to sell, let me know.
Thanks,
Glenn
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Chemical "nut busters" |
Just got this note from a cousin out in California . . .
---------------------------------------
Penetrating Oils Compared
Machinist's Workshop magazine actually tested penetrants for break
out torque on rusted nuts. Significant results! They arranged a subjective
test of all the popular penetrants with the control being the torque
required to remove the nut from a "scientifically rusted" environment.
Penetrating oil Average load
None ..................... 516 pounds
WD-40 .................. 238 pounds
PB Blaster ..............214 pounds
Liquid Wrench ...... 127 pounds
Kano Kroil ............ 106 pounds
ATF-Acetone mix... 53 pounds
The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
transmission fluid and acetone.
Note: The "home brew" was better than any commercial product in this
one particular test. A local machinist group mixed up a batch and all now
use it with equally good results. Note also that "Liquid Wrench" is about as
good as "Kroil" for about 20% of the price.
------------------------------------------
Kool Data! I have a can of Kroil that's
left over from our airport days. Bought it to refurbish
some parts on our tractor/hedge-hogg. But it's
interesting to see that one can do better yet
with some off-the-shelf ingredients. Would
be interested in hearing from members on
the list who have tried the home brew.
Bob . . .
________________________________________________________________________________
| From: | Marvin Haught <handainc(at)madisoncounty.net> |
| Subject: | Re: Chemical "nut busters" |
Bob -
I have been using "the brew" now for about a year, and am astonished at
how well it works. Recently I was tearing down a washer for repair, and
the tub nut was frozen in place (aluminum). All the repair directions
said to cut it off with a chisel and replace. I soaked it in "the brew"
for around an hour, ever so often, giving it a couple of whacks around
the perimeter with a hammer and a drift. When I put the wrench on it,
off it came like it was new! I have used it side by side with Liquid
wrench, and it works twice as fast. Drawbacks are that it is very
flammable, has to be kept in a closed container (I use old shampoo
bottles with the snap over tops and a short length of vinyl tubing in
the hole for a spout), and will ruin a paint job in a hurry. I'm on a
couple of machinist's websites and put the info on both of them
recently. All my buddies are using it now.
M. Haught
Robert L. Nuckolls, III wrote:
>
>
>
> Just got this note from a cousin out in California . . .
>
> ---------------------------------------
> Penetrating Oils Compared
>
> Machinist's Workshop magazine actually tested penetrants for break
> out torque on rusted nuts. Significant results! They arranged a
> subjective
> test of all the popular penetrants with the control being the torque
> required to remove the nut from a "scientifically rusted" environment.
>
> Penetrating oil Average load
>
> None ..................... 516 pounds
>
> WD-40 .................. 238 pounds
>
> PB Blaster ..............214 pounds
>
> Liquid Wrench ...... 127 pounds
>
> Kano Kroil ............ 106 pounds
>
> ATF-Acetone mix... 53 pounds
>
> The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
> transmission fluid and acetone.
>
> Note: The "home brew" was better than any commercial product in this
> one particular test. A local machinist group mixed up a batch and all now
> use it with equally good results. Note also that "Liquid Wrench" is
> about as
> good as "Kroil" for about 20% of the price.
>
> ------------------------------------------
>
> Kool Data! I have a can of Kroil that's
> left over from our airport days. Bought it to refurbish
> some parts on our tractor/hedge-hogg. But it's
> interesting to see that one can do better yet
> with some off-the-shelf ingredients. Would
> be interested in hearing from members on
> the list who have tried the home brew.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "JOHN TIPTON" <jmtipton(at)btopenworld.com> |
| Subject: | Re: Chemical "nut busters" |
Hi Guys
What is the significance of the 'automatic transmission fluid'
Regards
John
>> ---------------------------------------
>> Penetrating Oils Compared
>>
>> Machinist's Workshop magazine actually tested penetrants for break
>> out torque on rusted nuts. Significant results! They arranged a
>> subjective
>> test of all the popular penetrants with the control being the torque
>> required to remove the nut from a "scientifically rusted" environment.
>>
>> Penetrating oil Average load
>>
>> None ..................... 516 pounds
>>
>> WD-40 .................. 238 pounds
>>
>> PB Blaster ..............214 pounds
>>
>> Liquid Wrench ...... 127 pounds
>>
>> Kano Kroil ............ 106 pounds
>>
>> ATF-Acetone mix... 53 pounds
>>
>> The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
>> transmission fluid and acetone.
>>
>> Note: The "home brew" was better than any commercial product in this
>> one particular test. A local machinist group mixed up a batch and all now
>> use it with equally good results. Note also that "Liquid Wrench" is about
>> as
>> good as "Kroil" for about 20% of the price.
>>
>> ------------------------------------------
>>
>> Kool Data! I have a can of Kroil that's
>> left over from our airport days. Bought it to refurbish
>> some parts on our tractor/hedge-hogg. But it's
>> interesting to see that one can do better yet
>> with some off-the-shelf ingredients. Would
>> be interested in hearing from members on
>> the list who have tried the home brew.
>>
>> Bob . . .
>>
>>
>>
>>
>>
>
>
>
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
| Subject: | Chemical "nut busters" |
What is the significance of the 'automatic transmission fluid'
Regards
John
I would assume that this is the lubricant,
and the acetone is a strong solvent which carries it into the "nooks and
crannies" of the rusted assembly. Probably some other lubricant could be
used, but this apparently works!
Roger
________________________________________________________________________________
| From: | Marvin Haught <handainc(at)madisoncounty.net> |
| Subject: | Re: Chemical "nut busters" |
I don't know - we tried regular motor oil and it did not work as well.
M. Haught
ROGER & JEAN CURTIS wrote:
> What is the significance of the 'automatic transmission fluid'
>
> Regards
>
> John
>
>
> I would assume that this is the lubricant,
> and the acetone is a strong solvent which carries it into the "nooks and
> crannies" of the rusted assembly. Probably some other lubricant could be
> used, but this apparently works!
>
> Roger
>
>
>
________________________________________________________________________________
| From: | Harley <harley(at)AgelessWings.com> |
| Subject: | Re: Chemical "nut busters" |
ROGER & JEAN CURTIS wrote:
> What is the significance of the 'automatic transmission fluid'
>
> Regards
>
> John
>
>
> I would assume that this is the lubricant,
> and the acetone is a strong solvent which carries it into the "nooks and
> crannies" of the rusted assembly. Probably some other lubricant could be
> used, but this apparently works!
>
> Roger
>
In addition, ATF is a pretty good solvent in it's own right...besides
lubricating, it can dissolve lacquers, corrosion and other hard to
remove cruds. It is a recommended solvent for cleaning gun powder
fouling in firearms.
So, I would think that between the acetone's properties of being thin
and working into tiny spaces and being a solvent for most plastics, and
the additional solvent properties of the ATF and it's ability to stay
behind as a lubricant, it makes a good combination.
The containers of ATF do have warnings against getting it on your auto's
finish...
Harley
________________________________________________________________________________
| From: | David <ainut(at)hiwaay.net> |
| Subject: | Re: Chemical "nut busters" |
________________________________________________________________________________
| Subject: | HLMP-2685 multi-LEDs off LR3C |
| From: | James Kilford <james(at)etravel.org> |
Gents,
I'm putting together a small annunciator panel with a number of
HLMP-2685 (and similar) LED packages on it. Each one has 8 discrete
LEDs, which can be wired in series or parallel to work together. The
HLMP-2685 is red, and there are green, yellow, etc., available too.
http://parts.digikey.com/1/parts/681506-led-lt-bar-hi-eff-red-8led-dip-hlmp2685.html
I'd like to hook one of these to the LR3C regulator instead of the
supplied filament lamp, so that it can go into the annunciator panel
too.
I've been trying to trace a schematic of Bob's, which I'm sure I've
seen, of how to use an LED instead of a filament lamp with the LR3C,
as a starting point. I can't find it, and the resistor values would
be different in any case, so can anyone throw any light on to how to
use one of these 8-LED devices with the LR3C?
For the other uses of this HLMP-2685, e.g fuel pump, flaps, timer,
etc, I'd put four of the LEDs in series, paralleled with the other
four, with a 220ohm resistor, to run from a nominal 12V supply.
Any advice would be greatly appreciated. Many thanks in anticipation.
James
________________________________________________________________________________
| From: | David <ainut(at)knology.net> |
| Subject: | Re: Chemical "nut busters" |
________________________________________________________________________________
| From: | David <ainut(at)hiwaay.net> |
| Subject: | Re: Chemical "nut busters" |
________________________________________________________________________________
| From: | RGent1224(at)aol.com |
| Subject: | Re: Chemical "nut busters" |
Hey, Ainut, this is the third blank you have sent
What gives????????
________________________________________________________________________________
| From: | <robert.mccallum2(at)sympatico.ca> |
| Subject: | re Chemical "nut Busters" |
Thanks for passing this along Bob.
Great research info.
I'm also happy to see that these test results bear out my own observations over
many years as a mechanic restoring antique autos, that WD-40 is practically useless
and a waste of money. The other product which is not on the list, but which
I've found effective is called "Break Away" made by Cyclo Automotive Inc
of Elkhart Indiana. It would have been interesting to see this as well as additional
products on the list such as "Mouse Milk", and "Corrosion X" to further
the comparisons. The major drawback of the ATF/Acetone mixture is its propensity
to immediately remove paint and of course its extreme flammability. Used
carefully however it's the "cats a**" so to speak.
Bob McC
$B!!(B
Just got this note from a cousin out in California . . .
---------------------------------------
Penetrating Oils Compared
Machinist's Workshop magazine actually tested penetrants for break
out torque on rusted nuts. Significant results! They arranged a subjective
test of all the popular penetrants with the control being the torque
required to remove the nut from a "scientifically rusted" environment.
Penetrating oil Average load
None ..................... 516 pounds
WD-40 .................. 238 pounds
PB Blaster ..............214 pounds
Liquid Wrench ...... 127 pounds
Kano Kroil ............ 106 pounds
ATF-Acetone mix... 53 pounds
The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
transmission fluid and acetone.
Note: The "home brew" was better than any commercial product in this
one particular test. A local machinist group mixed up a batch and all now
use it with equally good results. Note also that "Liquid Wrench" is about as
good as "Kroil" for about 20% of the price.
------------------------------------------
Kool Data! I have a can of Kroil that's
left over from our airport days. Bought it to refurbish
some parts on our tractor/hedge-hogg. But it's
interesting to see that one can do better yet
with some off-the-shelf ingredients. Would
be interested in hearing from members on
the list who have tried the home brew.
Bob . . .
$B!!(B
$B!!(B
$B!!(B
$B!!(B
________________________________________________________________________________
| Subject: | Need New TNC male gold pin |
| From: | "johngoodman" <johngoodman(at)earthlink.net> |
I messed up my TNC male gold pin and need a new one. The TNC I have was pretty
pricey from Aircraft Spruce, but I did see an older thread with a link for one
much cheaper. Before I get a new one, is there any kind of source for just the
pins?
John
--------
#40572 QB. Working on Cowling & Panel
N711JG reserved
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293286#293286
________________________________________________________________________________
| From: | Marvin Haught <handainc(at)madisoncounty.net> |
| Subject: | Re: re Chemical "nut Busters" |
Robert -
I think you are right on - I only use "the brew" on rough old rusty
machinery, or something that I am reconditioning. You can get by with
less "dangerous" solvents on other stuff. I keep various solvents on
hand, as I am sure you do to - this is the "last resort" product where
either the stuff works, or you are going to end up drilling out the
bolts or worse to salvage the parts.
M. Haught
robert.mccallum2(at)sympatico.ca wrote:
> *Thanks for passing this along Bob. *
> *Great research info.*
> *I'm also happy to see that these test results bear out my own
> observations over many years as a mechanic restoring antique autos,
> that WD-40 is practically useless and a waste of money. The other
> product which is not on the list, but which I've found effective is
> called "Break Away" made by Cyclo Automotive Inc of Elkhart Indiana.
> It would have been interesting to see this as well as additional
> products on the list such as "Mouse Milk", and "Corrosion X" to
> further the comparisons. The major drawback of the ATF/Acetone mixture
> is its propensity to immediately remove paint and of course its
> extreme flammability. Used carefully however it's the "cats a**" so to
> speak.*
> **
> *Bob McC*
>
>
> $B!!(B
> Just got this note from a cousin out in California . . .
> ---------------------------------------
> Penetrating Oils Compared
> Machinist's Workshop magazine actually tested penetrants for break
> out torque on rusted nuts. Significant results! They arranged a subjective
> test of all the popular penetrants with the control being the torque
> required to remove the nut from a "scientifically rusted" environment.
> Penetrating oil Average load
> None ..................... 516 pounds
> WD-40 .................. 238 pounds
> PB Blaster ..............214 pounds
> Liquid Wrench ...... 127 pounds
> Kano Kroil ............ 106 pounds
> ATF-Acetone mix... 53 pounds
> The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
> transmission fluid and acetone.
> Note: The "home brew" was better than any commercial product in this
> one particular test. A local machinist group mixed up a batch and all now
> use it with equally good results. Note also that "Liquid Wrench" is
> about as
> good as "Kroil" for about 20% of the price.
> ------------------------------------------
> Kool Data! I have a can of Kroil that's
> left over from our airport days. Bought it to refurbish
> some parts on our tractor/hedge-hogg. But it's
> interesting to see that one can do better yet
> with some off-the-shelf ingredients. Would
> be interested in hearing from members on
> the list who have tried the home brew.
> Bob . . .
> $B!!(B
> $B!!(B
> $B!!(B
> $B!!(B
> *
>
>
> *
________________________________________________________________________________
| From: | David <ainut(at)hiwaay.net> |
| Subject: | probs with text AGAIN in emails & have forgotten the |
solution
________________________________________________________________________________
| Subject: | Re: Need New TNC male gold pin |
| From: | "Jim Berry" <jimberry(at)qwest.net> |
John,
I had the same situation several months ago, but had no joy from ACS, Stein, McMaster,
Digikey or Mouser. Good luck.
Jim Berry
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293302#293302
________________________________________________________________________________
| From: | "John F. Herminghaus" <catignano(at)tele2.it> |
| Subject: | Re: Used avionics |
Am interested in the ST-901. What is your asking price?
Tried to email you directly, but your server rejected my message as spam.
John Herminghaus
On 06/04/2010 04:53, Bill Hibbing wrote:
> Just thought that I'd pass along that I'm slowly changing over to
> glass so I have the following operable avionics for sale. I don't
> want to use the forum for advertising so if you have any interest in
> any of the items please email me direct and I' send you the price.
> 1. King KT-76A transponder wired for and including an Ameriking
> AK-350 altitude encoder.
> 2. STec ST-901 GPSS converter for STec A/P's.
> 3. 52D54 Autopilot directional gyro
> 4. JP instruments EDM-700 engine data monitor with new EGT and CHT
> probes and STC paperwork for TC airplanes.
> Bill Hibbing
> Glasair
> *
>
>
> *
________________________________________________________________________________
| From: | David <ainut(at)hiwaay.net> |
| Subject: | Re: re Chemical "nut Busters" |
maybe it will work this time. same problem as before.
regarding current thread:
Please do not use the acetone and *anything* in closed quarters. In
fact, if possible, have a fan blowing the fumes away from you while
using. I don't know of ATF will keep acetone from immediately drying
into the air, but don't chance it.
David
Marvin Haught wrote:
>
> Robert -
>
> I think you are right on - I only use "the brew" on rough old rusty
> machinery, or something that I am reconditioning. You can get by with
> less "dangerous" solvents on other stuff. I keep various solvents on
> hand, as I am sure you do to - this is the "last resort" product where
> either the stuff works, or you are going to end up drilling out the
> bolts or worse to salvage the parts.
>
> M. Haught
>
>
> robert.mccallum2(at)sympatico.ca wrote:
>
>> *Thanks for passing this along Bob. *
>> *Great research info.*
>> *I'm also happy to see that these test results bear out my own
>> observations over many years as a mechanic restoring antique autos,
>> that WD-40 is practically useless and a waste of money. The other
>> product which is not on the list, but which I've found effective is
>> called "Break Away" made by Cyclo Automotive Inc of Elkhart Indiana.
>> It would have been interesting to see this as well as additional
>> products on the list such as "Mouse Milk", and "Corrosion X" to
>> further the comparisons. The major drawback of the ATF/Acetone mixture
>> is its propensity to immediately remove paint and of course its
>> extreme flammability. Used carefully however it's the "cats a**" so to
>> speak.*
>> **
>> *Bob McC*
>>
>>
>>
>> Just got this note from a cousin out in California . . .
>> ---------------------------------------
>> Penetrating Oils Compared
>> Machinist's Workshop magazine actually tested penetrants for break
>> out torque on rusted nuts. Significant results! They arranged a subjective
>> test of all the popular penetrants with the control being the torque
>> required to remove the nut from a "scientifically rusted" environment.
>> Penetrating oil Average load
>> None ..................... 516 pounds
>> WD-40 .................. 238 pounds
>> PB Blaster ..............214 pounds
>> Liquid Wrench ...... 127 pounds
>> Kano Kroil ............ 106 pounds
>> ATF-Acetone mix... 53 pounds
>> The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
>> transmission fluid and acetone.
>> Note: The "home brew" was better than any commercial product in this
>> one particular test. A local machinist group mixed up a batch and all now
>> use it with equally good results. Note also that "Liquid Wrench" is
>> about as
>> good as "Kroil" for about 20% of the price.
>> ------------------------------------------
>> Kool Data! I have a can of Kroil that's
>> left over from our airport days. Bought it to refurbish
>> some parts on our tractor/hedge-hogg. But it's
>> interesting to see that one can do better yet
>> with some off-the-shelf ingredients. Would
>> be interested in hearing from members on
>> the list who have tried the home brew.
>> Bob . . .
>>
>>
>>
>>
>> *
>>
>>
>> *
>>
>
>
>
________________________________________________________________________________
| From: | Marvin Haught <handainc(at)madisoncounty.net> |
| Subject: | Re: re Chemical "nut Busters" |
Very good point, and why I call it a "dangerous" mix, both to health and
what you are working on if it is painted. The good thing is the acetone
is so volatile that it evaporates quickly, but also why it is a threat
in close quarters.
M. Haught
David wrote:
>
> maybe it will work this time. same problem as before.
>
> regarding current thread:
> Please do not use the acetone and *anything* in closed quarters. In
> fact, if possible, have a fan blowing the fumes away from you while
> using. I don't know of ATF will keep acetone from immediately drying
> into the air, but don't chance it.
>
> David
>
>
> Marvin Haught wrote:
>>
>>
>> Robert -
>>
>> I think you are right on - I only use "the brew" on rough old rusty
>> machinery, or something that I am reconditioning. You can get by with
>> less "dangerous" solvents on other stuff. I keep various solvents on
>> hand, as I am sure you do to - this is the "last resort" product where
>> either the stuff works, or you are going to end up drilling out the
>> bolts or worse to salvage the parts.
>>
>> M. Haught
>>
>>
>> robert.mccallum2(at)sympatico.ca wrote:
>>
>>> *Thanks for passing this along Bob. *
>>> *Great research info.*
>>> *I'm also happy to see that these test results bear out my own
>>> observations over many years as a mechanic restoring antique autos,
>>> that WD-40 is practically useless and a waste of money. The other
>>> product which is not on the list, but which I've found effective is
>>> called "Break Away" made by Cyclo Automotive Inc of Elkhart Indiana.
>>> It would have been interesting to see this as well as additional
>>> products on the list such as "Mouse Milk", and "Corrosion X" to
>>> further the comparisons. The major drawback of the ATF/Acetone mixture
>>> is its propensity to immediately remove paint and of course its
>>> extreme flammability. Used carefully however it's the "cats a**" so to
>>> speak.*
>>> **
>>> *Bob McC*
>>>
>>>
>>>
>>> Just got this note from a cousin out in California . . .
>>> ---------------------------------------
>>> Penetrating Oils Compared
>>> Machinist's Workshop magazine actually tested penetrants for break
>>> out torque on rusted nuts. Significant results! They arranged a
>>> subjective
>>> test of all the popular penetrants with the control being the torque
>>> required to remove the nut from a "scientifically rusted" environment.
>>> Penetrating oil Average load
>>> None ..................... 516 pounds
>>> WD-40 .................. 238 pounds
>>> PB Blaster ..............214 pounds
>>> Liquid Wrench ...... 127 pounds
>>> Kano Kroil ............ 106 pounds
>>> ATF-Acetone mix... 53 pounds
>>> The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
>>> transmission fluid and acetone.
>>> Note: The "home brew" was better than any commercial product in this
>>> one particular test. A local machinist group mixed up a batch and
>>> all now
>>> use it with equally good results. Note also that "Liquid Wrench" is
>>> about as
>>> good as "Kroil" for about 20% of the price.
>>> ------------------------------------------
>>> Kool Data! I have a can of Kroil that's
>>> left over from our airport days. Bought it to refurbish
>>> some parts on our tractor/hedge-hogg. But it's
>>> interesting to see that one can do better yet
>>> with some off-the-shelf ingredients. Would
>>> be interested in hearing from members on
>>> the list who have tried the home brew.
>>> Bob . . .
>>>
>>>
>>>
>>>
>>> *
>>>
>>>
>>> *
>>>
>>
>>
>>
>>
>>
>>
>>
>
>
________________________________________________________________________________
| From: | "Fisher Paul A." <FisherPaulA(at)johndeere.com> |
| Subject: | Chemical "nut busters" |
Bob,
I had seen that note a few months ago. Over this last winter I had to replace
an engine on a log splitter. Since it had been together for 25+ years, everything
was pretty well rusted together. With nothing to lose, I tried the "home
brew" and it worked exactly as advertised! I was working outside, and removing
paint was not an issue, so none of the concerns expressed on the list were
an issue for me. I was as surprised as anyone how well the brew worked. I certainly
recommend it for seriously rusted together parts!
Paul A. Fisher
Q-200, N17PF
RV-7A, N18PF
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
| Subject: | re Chemical "nut Busters" |
The good thing is the acetone
is so volatile that it evaporates quickly, but also why it is a threat
in close quarters.
M. Haught
Two reasons it is a threat in close quarters: 1. It is very
flammable. 2. It is absorbed into your body very readily through the skin
and also through the lungs. Small amounts are not considered very harmful
but continued exposure can be. Read the MSDS.
Roger
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Need New TNC male gold pin |
At 08:51 PM 4/6/2010, you wrote:
>
>
>I messed up my TNC male gold pin and need a new one. The TNC I have
>was pretty pricey from Aircraft Spruce, but I did see an older
>thread with a link for one much cheaper. Before I get a new one, is
>there any kind of source for just the pins?
None that I know of. Years ago, we needed a batch of
loose pins for some coax connectors and went to
TED Mfg to order several thousand. But nobody stocks
them as low-quantity, off-the-shelf items.
Your best bet is to replace the whole connector.
Ebay offers them pretty inexpensively but often
the postage is more than the connector!
Bob . . .
________________________________________________________________________________
| From: | "David E. Nelson" <david.nelson(at)pobox.com> |
| Subject: | Re: Chemical "nut busters" |
Hi Bob,
Thank you for forwarding this great info on. I was pondering this info while
driving into work this AM and came up with a couple of curiosity questions:
- How long were the assemblies exposed to the penetrants before applying the
torque (seconds, minutes, hours, days)?
- Is there any data for 'torque vs time' - ie. How much torque to break an
assembly vs time exposed to the penetrants?
Also, I would imagine that the assemblies would have to be _very_ clean before
re-assembling them - particularly for the 'home brew' stuff since it offers
nearly 10x reduction in torque.
Regards,
/\/elson
~~ Lately my memory seems to be like a steel trap .... without any spring. ~~
On Tue, 6 Apr 2010, Robert L. Nuckolls, III wrote:
>
>
>
> Just got this note from a cousin out in California . . .
>
> ---------------------------------------
> Penetrating Oils Compared
>
> Machinist's Workshop magazine actually tested penetrants for break
> out torque on rusted nuts. Significant results! They arranged a subjective
> test of all the popular penetrants with the control being the torque
> required to remove the nut from a "scientifically rusted" environment.
>
> Penetrating oil Average load
>
> None ..................... 516 pounds
>
> WD-40 .................. 238 pounds
>
> PB Blaster ..............214 pounds
>
> Liquid Wrench ...... 127 pounds
>
> Kano Kroil ............ 106 pounds
>
> ATF-Acetone mix... 53 pounds
>
> The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
> transmission fluid and acetone.
>
> Note: The "home brew" was better than any commercial product in this
> one particular test. A local machinist group mixed up a batch and all now
> use it with equally good results. Note also that "Liquid Wrench" is about as
> good as "Kroil" for about 20% of the price.
>
> ------------------------------------------
>
> Kool Data! I have a can of Kroil that's
> left over from our airport days. Bought it to refurbish
> some parts on our tractor/hedge-hogg. But it's
> interesting to see that one can do better yet
> with some off-the-shelf ingredients. Would
> be interested in hearing from members on
> the list who have tried the home brew.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | ray <raymondj(at)frontiernet.net> |
| Subject: | Re: Chemical "nut busters" |
Here's one I have used a few times and it seems to work well. 1 oz of
wintergreen oil (available at a pharmacy) with 1/2 gal diesel fuel is
the formula I have seen. When I've used it, I mix small (<1oz) batches
of wintergreen and air tool oil ('cause it was close at hand and low
viscosity).
Raymond Julian
Kettle River, MN.
Robert L. Nuckolls, III wrote:
>
>
>
> Just got this note from a cousin out in California . . .
>
> ---------------------------------------
> Penetrating Oils Compared
>
> Machinist's Workshop magazine actually tested penetrants for break
> out torque on rusted nuts. Significant results! They arranged a subjective
> test of all the popular penetrants with the control being the torque
> required to remove the nut from a "scientifically rusted" environment.
>
> Penetrating oil Average load
>
> None ..................... 516 pounds
>
> WD-40 .................. 238 pounds
>
> PB Blaster ..............214 pounds
>
> Liquid Wrench ...... 127 pounds
>
> Kano Kroil ............ 106 pounds
>
> ATF-Acetone mix... 53 pounds
>
> The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
> transmission fluid and acetone.
>
> Note: The "home brew" was better than any commercial product in this
> one particular test. A local machinist group mixed up a batch and all now
> use it with equally good results. Note also that "Liquid Wrench" is
> about as
> good as "Kroil" for about 20% of the price.
>
> ------------------------------------------
>
> Kool Data! I have a can of Kroil that's
> left over from our airport days. Bought it to refurbish
> some parts on our tractor/hedge-hogg. But it's
> interesting to see that one can do better yet
> with some off-the-shelf ingredients. Would
> be interested in hearing from members on
> the list who have tried the home brew.
>
> Bob . . .
>
>
>
>
>
>
________________________________________________________________________________
| From: | "jakent(at)unison.ie" <jakent(at)unison.ie> |
| Subject: | RE:Chemical nut busters. |
Now the Honours question!
Lots of RVers have reported using ATF fluid instead of aircraft brake fluid.
Will aircraft brake fluid work in the 'nut-buster' mixture instead of ATF
liquid?
Some of our number have it still on our shelves.
Rgds John Kent RV-4 (EI-DIY).
--------------------------------------------------------------------
mail2web.com Enhanced email for the mobile individual based on Microsoft
Exchange - http://link.mail2web.com/Personal/EnhancedEmail
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Chemical "nut busters" |
At 09:10 AM 4/7/2010, you wrote:
Hi Bob,
Thank you for forwarding this great info on. I was pondering this
info while driving into work this AM and came up with a couple of
curiosity questions:
- How long were the assemblies exposed to the penetrants before
applying the torque (seconds, minutes, hours, days)?
I Did a web search on "ATF" and "acetone" and got a gob
of hits. Seems the original author of the article
did an update of the article but the website link
is broken. I think the site is defunct. Did find this
bit on at:
------------------------------
http://mytractorforum.com/showthread.php?t=99250
------------------------------
This same quote has been circulated over the internet for a while but
if you actually read the article you will find:
The scientifically rusted environment was just 12 hours in salt water.
No bolts, no nuts but just dowel pins rusted into a block of steel.
A 8 hour soaking in the penetrating oil not just a few sprays.
There was no ATF but it was a 50-50 mix of acetone and power steering fluid.
Power steering fluid and acetone do not mix well, it will separate
into two layers because acetone is relatively polar.
How valid was his study? From what I could tell from the article, it
was really not valid. I suggest getting a copy of the article and
deciding for your self.
-------------------------------
The ATF/Acetone thing is very widely spread
on 'net. Almost viral. A search on "power steering
fluid" and "acetone" yielded a bunch of articles
on hazardous waste disposal.
Would be interesting to pursue further but I'm painting
cabinets today . . .
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: HLMP-2685 multi-LEDs off LR3C |
>
>http://parts.digikey.com/1/parts/681506-led-lt-bar-hi-eff-red-8led-dip-hlmp2685.html
>
>I'd like to hook one of these to the LR3C regulator instead of the
>supplied filament lamp, so that it can go into the annunciator panel
>too.
>
>I've been trying to trace a schematic of Bob's, which I'm sure I've
>seen, of how to use an LED instead of a filament lamp with the LR3C,
>as a starting point. I can't find it, and the resistor values would
>be different in any case, so can anyone throw any light on to how to
>use one of these 8-LED devices with the LR3C?
The schematic I published is at:
http://aeroelectric.com/Pictures/Schematics/LR3_LV_Led_1.jpg
Your application will take some experimentation.
You can try paralleling all the LEDs and seeing how
well you can excite the array and still have uniform
illumination. You may find that you need to treat
them as separate LEDs.
Just be aware that LR3 lamp driver is never completely
"OFF". The off current is too low to get any light
from a bulb but it will cause an LED to glow at a
reduced intensity. Hence the paralleling resistor to
get the LED to mimic a lamp more closely.
Bob . . .
________________________________________________________________________________
| From: | "William Greenley" <wgreenley(at)gmail.com> |
| Subject: | Chemical "nut busters" |
I have teach some advanced high school classes where the students are always
looking for interesting projects for science fairs. This research might be a
good fit. What thoughts does anyone have on how to "scientifically" within a
reasonable time frame get a bunch of comparably rusted bolts? Also, any
ideas on what application protocol for the "nut busters" would be most
useful?
Dr Greenley
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Thursday, April 08, 2010 8:59 AM
Subject: Re: AeroElectric-List: Chemical "nut busters"
At 09:10 AM 4/7/2010, you wrote:
Hi Bob,
Thank you for forwarding this great info on. I was pondering this
info while driving into work this AM and came up with a couple of
curiosity questions:
- How long were the assemblies exposed to the penetrants before
applying the torque (seconds, minutes, hours, days)?
I Did a web search on "ATF" and "acetone" and got a gob
of hits. Seems the original author of the article
did an update of the article but the website link
is broken. I think the site is defunct. Did find this
bit on at:
------------------------------
http://mytractorforum.com/showthread.php?t=99250
------------------------------
This same quote has been circulated over the internet for a while but
if you actually read the article you will find:
The scientifically rusted environment was just 12 hours in salt water.
No bolts, no nuts but just dowel pins rusted into a block of steel.
A 8 hour soaking in the penetrating oil not just a few sprays.
There was no ATF but it was a 50-50 mix of acetone and power steering fluid.
Power steering fluid and acetone do not mix well, it will separate
into two layers because acetone is relatively polar.
How valid was his study? From what I could tell from the article, it
was really not valid. I suggest getting a copy of the article and
deciding for your self.
-------------------------------
The ATF/Acetone thing is very widely spread
on 'net. Almost viral. A search on "power steering
fluid" and "acetone" yielded a bunch of articles
on hazardous waste disposal.
Would be interesting to pursue further but I'm painting
cabinets today . . .
Bob . . .
________________________________________________________________________________
| From: | Robert Borger <rlborger(at)mac.com> |
| Subject: | Re: Chemical "nut busters" |
Dr. G,
I'd say you have at least two nice projects here.
1. Studying corrosion
Compare solutions of water, water with NaCl, water with CaCl, water
with both, on cheap, unplated, hardware bolts/nuts over time (days/
weeks/months).
2. Once you get a suitable set of corroded bolts/nuts, what works best
to separate them.
I'll think more about the necessary protocols until I return home and
can write more easily.
Regards,
Bob Borger
Sent from my iPhone
On Apr 8, 2010, at 9:26, William Greenley wrote:
> >
>
> I have teach some advanced high school classes where the students
> are always
> looking for interesting projects for science fairs. This research
> might be a
> good fit. What thoughts does anyone have on how to "scientifically"
> within a
> reasonable time frame get a bunch of comparably rusted bolts? Also,
> any
> ideas on what application protocol for the "nut busters" would be most
> useful?
> Dr Greenley
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
> Robert L.
> Nuckolls, III
> Sent: Thursday, April 08, 2010 8:59 AM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Chemical "nut busters"
>
>
>
>
> At 09:10 AM 4/7/2010, you wrote:
>
>
>
> Hi Bob,
>
> Thank you for forwarding this great info on. I was pondering this
> info while driving into work this AM and came up with a couple of
> curiosity questions:
>
> - How long were the assemblies exposed to the penetrants before
> applying the torque (seconds, minutes, hours, days)?
>
> I Did a web search on "ATF" and "acetone" and got a gob
> of hits. Seems the original author of the article
> did an update of the article but the website link
> is broken. I think the site is defunct. Did find this
> bit on at:
>
> ------------------------------
> http://mytractorforum.com/showthread.php?t=99250
> ------------------------------
> This same quote has been circulated over the internet for a while but
> if you actually read the article you will find:
>
> The scientifically rusted environment was just 12 hours in salt water.
>
> No bolts, no nuts but just dowel pins rusted into a block of steel.
>
> A 8 hour soaking in the penetrating oil not just a few sprays.
>
> There was no ATF but it was a 50-50 mix of acetone and power
> steering fluid.
> Power steering fluid and acetone do not mix well, it will separate
> into two layers because acetone is relatively polar.
>
> How valid was his study? From what I could tell from the article, it
> was really not valid. I suggest getting a copy of the article and
> deciding for your self.
> -------------------------------
>
> The ATF/Acetone thing is very widely spread
> on 'net. Almost viral. A search on "power steering
> fluid" and "acetone" yielded a bunch of articles
> on hazardous waste disposal.
>
> Would be interesting to pursue further but I'm painting
> cabinets today . . .
>
> Bob . . .
>
>
________________________________________________________________________________
| Subject: | Delete if you wish, but this is funny! |
| From: | rparigor(at)suffolk.lib.ny.us |
You have to have an engineer’s
personality to understand why it is so funny. Enjoy
Reciprocating Dingle
Arm
This is a very funny and classic
presentation organized by
Rockwell Int'l. Read the introduction
before clicking on the video
link below.
Several years
ago, Rockwell International decided to get into
the heavy duty
transmission business. They were getting ready
to tape a first
introduction video, and as a warm up, the
professional narrator began
what has become a legend within the
trucking industry. This man
should have won an academy award for his
stellar performance.
Now remember this is strictly off the cuff,
nothing is written down,
this became the biggest talk in the
industry, vs the new product
which they were introducing.
Click here: http://home.comcast.net/~steveham21/turbo.mpg
________________________________________________________________________________
| Subject: | Delete if you wish, but this is funny! |
What player or codec did you use to play the video?
The Media Player in Windows 7 gives this error message:
"\Windows Media Player cannot play the file. The Player might not support
the file type or might not support the codec that was used to compress the
file."
Best regards,
Rob Housman
Irvine, CA
Europa XS Tri-Gear
A070
Airframe complete
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
rparigor(at)suffolk.lib.ny.us
Sent: Thursday, April 08, 2010 5:31 PM
Subject: AeroElectric-List: Delete if you wish, but this is funny!
You have to have an engineer's personality to understand why it is so funny.
Enjoy
Reciprocating Dingle Arm
This is a very funny and classic presentation organized by
Rockwell Int'l. Read the introduction before clicking on the video
link below.
Several years ago, Rockwell International decided to get into
the heavy duty transmission business. They were getting ready
to tape a first introduction video, and as a warm up, the
professional narrator began what has become a legend within the
trucking industry. This man should have won an academy award for his
stellar performance. Now remember this is strictly off the cuff,
nothing is written down, this became the biggest talk in the
industry, vs the new product which they were introducing.
Click here: <http://home.comcast.net/~steveham21/turbo.mpg>
http://home.comcast.net/~steveham21/turbo.mpg
________________________________________________________________________________
| Subject: | Re: Delete if you wish, but this is funny! |
| From: | Dj Merrill <deej(at)deej.net> |
On 4/8/2010 10:46 PM, Rob Housman wrote:
> What player or codec did you use to play the video?
Try VLC, it plays just about everything:
<http://www.videolan.org/>
http://www.videolan.org/
-Dj
--
Dj Merrill - N1JOV
Glastar Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/
Grumman Yankee Driver N9870L - http://deej.net/yankee/
________________________________________________________________________________
| Subject: | Peer Review of Schematic |
| From: | "Noah" <sgninc(at)cox.net> |
Greetings-
I am requesting comments on the following dual alternator single battery schematic
using Plane Power 60A and B&C SD-20 alternators using an external SB-1B regulator.
http://img88.imageshack.us/img88/4748/100408.png
Plane is an RV which will be equipped with a magneto and an EI, so engine is not
electrically dependent. Mission is multi-day X-country with occasional IFR.
Avionics suite will include EFIS/EM, IFR GPS, and autopilot. Backup flight instruments
(AI, ALT, AS) are planned. EFIS and AI will contain internal backup
batteries. Design goal is to keep it as simple as the mission allows.
Thanks in advance for your thoughts and consideration.
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293590#293590
________________________________________________________________________________
| From: | Harley <harley(at)AgelessWings.com> |
| Subject: | Re: Delete if you wish, but this is funny! |
Hmmm...it played fine in Windows Media player (Windows 7) here...
Harley
------------------------------------------------------------------------
Rob Housman wrote:
>
> What player or codec did you use to play the video?
>
>
>
> The Media Player in Windows 7 gives this error message:
>
>
>
> "\Windows Media Player cannot play the file. The Player might not
> support the file type or might not support the codec that was used to
> compress the file."
>
>
>
>
>
> Best regards,
>
>
>
> Rob Housman
>
> Irvine, CA
>
> Europa XS Tri-Gear
>
> A070
>
> Airframe complete
>
>
>
>
>
>
>
> *From:* owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] *On Behalf Of
> *rparigor(at)suffolk.lib.ny.us
> *Sent:* Thursday, April 08, 2010 5:31 PM
> *To:* AeroelectricList
> *Subject:* AeroElectric-List: Delete if you wish, but this is funny!
>
>
>
> You have to have an engineer's personality to understand why it is so
> funny. Enjoy
>
> *_Reciprocating Dingle Arm_**_
> _*
> This is a very funny and classic presentation organized by
> Rockwell Int'l. Read the introduction before clicking on the video
> link below.
>
> Several years ago, Rockwell International decided to get into
> the heavy duty transmission business. They were getting ready
> to tape a first introduction video, and as a warm up, the
> professional narrator began what has become a legend within the
> trucking industry. This man should have won an academy award for his
> stellar performance. Now remember this is strictly off the cuff,
> nothing is written down, this became the biggest talk in the
> industry, vs the new product which they were introducing.
>
>
> Click here: *http://home.comcast.net/~steveham21/turbo.mpg*
> <http://home.comcast.net/%7Esteveham21/turbo.mpg>
>
> * *
> * *
> **
> **
> **
> **
> **
> **
> *http://www.matronics.com/Navigator?AeroElectric-List*
> **
> **
> **
> *http://forums.matronics.com*
> **
> **
> **
> **
> *http://www.matronics.com/contribution*
> **
> * *
> *
>
>
> *
> ------------------------------------------------------------------------
>
>
> Checked by AVG - www.avg.com
>
>
________________________________________________________________________________
| From: | Robert Buls <bulsr(at)bellsouth.net> |
| Subject: | Re: Delete if you wish, but this is funny! |
Yes, but is the "Turbo-encabulator" an outgrowth of, or a practical applica
tion of, principles developed by Rockwell's incredibly versatile "Retro-enc
abulator", already known to be in development? =0A=0A=0A=0A=0A_____________
___________________=0AFrom: Harley <harley(at)AgelessWings.com>=0ATo: aeroelec
tric-list(at)matronics.com=0ASent: Fri, April 9, 2010 7:14:20 AM=0ASubject: Re
: AeroElectric-List: Delete if you wish, but this is funny!=0A=0AHmmm...it
played fine in Windows Media player (Windows 7) here...=0A=0AHarley=0A =0A
________________________________=0A=0ARob Housman wrote: =0A> =0A> > =0A>
What=0A>player or codec did you use to play the video?=0A> =0A>The=0A>Media
Player in Windows 7 gives this error message:=0A> =0A>=9C\Windows=0A
>Media Player cannot play the file. The Player might not support the=0A>fil
e type or=0A>might not support the codec that was used to compress the file
.=9D=0A> =0A> =0A>Best=0A>regards,=0A> =0A>Rob=0A>Housman=0A>Irvine,
=0A>CA =0A>Europa=0A>XS Tri-Gear=0A>A070=0A>Airframe=0A>complete=0A> =0A>
=0A> =0A>From:owner-aeroelectric-list-server(at)matronics.com >[mailto:owner-a
eroelectric-list-server(at)matronics.com] On Behalf Of rparigor(at)suffolk.lib.ny
.us=0A>Sent: Thursday, April 08, 2010 5:31 PM=0A>To: AeroelectricList=0A>Su
bject: AeroElectric-List: Delete if you wish, but this is=0A>funny!=0A> =0A
>You have to have an engineer=99s=0A>personality to understand why it
is so funny. Enjoy =0A> Reciprocating=0A>Dingle Arm=0A>=0A>>This is a ver
y funny and classic presentation organized by=0A>>Rockwell Int'l. Read the
introduction before clicking on the video=0A>>link below.=0A>=0A>>Several y
ears ago, Rockwell International decided to get into=0A>>the heavy duty tra
nsmission business. They were getting ready=0A>>to tape a first introducti
on video, and as a warm up, the=0A>>professional narrator began what has be
come a legend within the=0A>>trucking industry. This man should have won a
n academy award for his=0A>>stellar performance. Now remember this is stri
ctly off the cuff,=0A>>nothing is written down, this became the biggest tal
k in the=0A>>industry, vs the new product which they were introducing. =0A>
=0A>=0A>=0A>> Click here: http://home.comcast.net/~steveham21/turbo.mpg
=0A> =0A> =0A>http://www.matronics.com/Navigator?AeroElectric-List=0A>htt
p://forums.matronics.com=0A>http://www.matronics.com/contribution=0A> =0A>
=0A>=0A> href="http://www.matronics.com/Navigator?AeroElectric-List">http
://www.matronics.com/Navigator?AeroElectric-List=0A> href="http://forums.
matronics.com">http://forums.matronics.com=0A> href="http://www.matronics
.com/contribution">http://www.matronics.com/contribution =0A>=0A>=0A_______
_________________________=0A=0A>=0A>Checked by AVG - www.avg.com =0A>=0A>
=====================
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Peer Review of Schematic |
At 10:08 PM 4/8/2010, you wrote:
>
>Greetings-
>
>I am requesting comments on the following dual alternator single
>battery schematic using Plane Power 60A and B&C SD-20 alternators
>using an external SB-1B regulator.
>
>http://img88.imageshack.us/img88/4748/100408.png
When you post a customized power distribution diagram
it would be most helpful if you also include design
goals you expect to achieve that are over and above
what was published in the nearest Z-figure match.
One presumes that some design goal deficiency is
perceived with an existing z-figure. This would prompt
development of a new configuration. Without knowing
what those deficiencies are, it's difficult if not
impossible to evaluate effectiveness of the new
configuration for meeting design goals.
What drove the decision to use an SD-20 in lieu
of the lighter and much less expensive SD-8?
Bob . . .
________________________________________________________________________________
| From: | Ron Quillin <rjquillin(at)cox.net> |
| Subject: | Delete if you wish, but this is funny! |
At 19:46 4/8/2010, you wrote:
>From: "Rob Housman" <europa@hyperion-ef.com>
>
>What player or codec did you use to play the video?
>
>The Media Player in Windows 7 gives this error message:
Player 11 works fine.
Time for a free upgrade?
>
>"\Windows Media Player cannot play the file. The Player might not
>support the file type or might not support the codec that was used
>to compress the file."
>
>
>Best regards,
>
>Rob Housman
>Irvine, CA
>Europa XS Tri-Gear
>A070
>Airframe complete
>
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "jonlaury" <jonlaury(at)impulse.net> |
Noah,
Thanks for posting your schematic. As you know, I'm doing something similar because
Z-13, with an SD-8, does not meet the needs of my all electric plane with
high Ebus loads. I opted for a 40a Alt over the SD-20 largely because of cost
and a small weight penalty.
Questions:
1. Why the HE sensor and the shunt for the SD-20?
2. Part # for the HE sensor?
3. What kind of device is "Midi 30"?
4. "AFS"?
Thanks,
John
Glasair IIS-TD
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293663#293663
________________________________________________________________________________
| From: | "David LLoyd" <skywagon(at)charter.net> |
| Subject: | Re: Delete if you wish, but this is funny! |
If the "comcast.net" link does not work, then get YouTube up on your
computer and search for "Turboencabulator". There are several versions
of this technosmoke'em video.
D
-------------------------------------------------------------------------
-------
----- Original Message -----
From: Robert Buls
To: aeroelectric-list(at)matronics.com
Sent: Friday, April 09, 2010 5:56 AM
Subject: Re: AeroElectric-List: Delete if you wish, but this is funny!
Yes, but is the "Turbo-encabulator" an outgrowth of, or a practical
application of, principles developed by Rockwell's incredibly versatile
"Retro-encabulator", already known to be in development?
-------------------------------------------------------------------------
-----
From: Harley <harley(at)AgelessWings.com>
To: aeroelectric-list(at)matronics.com
Sent: Fri, April 9, 2010 7:14:20 AM
Subject: Re: AeroElectric-List: Delete if you wish, but this is funny!
Hmmm...it played fine in Windows Media player (Windows 7) here...
Harley
-------------------------------------------------------------------------
-----
Rob Housman wrote:
What player or codec did you use to play the video?
The Media Player in Windows 7 gives this error message:
=9C\Windows Media Player cannot play the file. The Player
might not support the file type or might not support the codec that was
used to compress the file.=9D
Best regards,
Rob Housman
Irvine, CA
Europa XS Tri-Gear
A070
Airframe complete
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
rparigor(at)suffolk.lib.ny.us
Sent: Thursday, April 08, 2010 5:31 PM
To: AeroelectricList
Subject: AeroElectric-List: Delete if you wish, but this is funny!
You have to have an engineer=99s personality to understand why
it is so funny. Enjoy
Reciprocating Dingle Arm
This is a very funny and classic presentation organized by
Rockwell Int'l. Read the introduction before clicking on the video
link below.
Several years ago, Rockwell International decided to get into
the heavy duty transmission business. They were getting ready
to tape a first introduction video, and as a warm up, the
professional narrator began what has become a legend within the
trucking industry. This man should have won an academy award for
his
stellar performance. Now remember this is strictly off the cuff,
nothing is written down, this became the biggest talk in the
industry, vs the new product which they were introducing.
Click here: http://home.comcast.net/~steveham21/turbo.mpg
http://www.matronics.com/Navigator?AeroElectric-Listhttp://forums.matroni
cs.comhttp://www.matronics.com/contribution
href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.
matronics.com/Navigator?AeroElectric-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
ontribution
-------------------------------------------------------------------------
---
Checked by AVG - www.avg.com http://www.matronics.cofollow"
target="_blank"
href="http://forums.matronics.com">http://forum========
=
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "Noah" <sgninc(at)cox.net> |
nuckolls.bob(at)aeroelect wrote:
> At 10:08 PM 4/8/2010, you wrote:
> When you post a customized power distribution diagram
> it would be most helpful if you also include design
> goals you expect to achieve that are over and above
> what was published in the nearest Z-figure match.
>
> One presumes that some design goal deficiency is
> perceived with an existing z-figure. This would prompt
> development of a new configuration. Without knowing
> what those deficiencies are, it's difficult if not
> impossible to evaluate effectiveness of the new
> configuration for meeting design goals.
>
> What drove the decision to use an SD-20 in lieu
> of the lighter and much less expensive SD-8?
>
> Bob . . .
Bob, didn't we already hash these questions out?
http://forums.matronics.com/viewtopic.php?p=288883#288883
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293688#293688
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "Noah" <sgninc(at)cox.net> |
jonlaury wrote:
> Noah,
>
> Thanks for posting your schematic. As you know, I'm doing something similar because
Z-13, with an SD-8, does not meet the needs of my all electric plane with
high Ebus loads. I opted for a 40a Alt over the SD-20 largely because of cost
and a small weight penalty.
>
> Questions:
> 1. Why the HE sensor and the shunt for the SD-20?
> 2. Part # for the HE sensor?
> 3. What kind of device is "Midi 30"?
> 4. "AFS"?
>
> Thanks,
> John
> Glasair IIS-TD
Thanks for the questions John.
1. The Hall Effect Sensor on the SD-20 B-Lead is actually part of the SB1B regulator
kit. With this regulator, the alternator is only brought to life if the
bus voltage falls to around 13V (main alternator failed/offline). The HE sensor
will trigger the regulator to continuously flash the annunciator light if
B-Lead current exceeds 20A, signaling to the pilot to reduce load. If B-Lead
current is below 20A, the annunciator will remain steady-lit. The second current
sensor on the B-Lead goes to the Advanced Flight Systems (AFS) to indicate
current load to the pilot, which can not be determined via the HE sensor on
the regulator (unless all you want to know is whether B-Lead load is 20A).
2. Part of SB1B-14 kit.
3. Midi 30 fuses:
http://www.littelfuse.com/data/en/Data_Sheets/498.pdf
I like these fuseblocks since they are rugged and covered for protection. And
McMaster-Carr sells the fuseblocks, P/N 9180K6.
4. Advanced Flight Systems - EFIS/Engine Monitor.
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293692#293692
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
| Subject: | Lithium backup power |
Bob,
You've probably already heard about this. Any comments?
The huge advancements in lithium battery technology that have improved
consumer products ranging from cell phones and laptop computers to electric
cars will soon arrive in aircraft. Mid-Continent Instruments recently
certified an emergency power supply known as the MD835, which is designed to keep
electric attitude indicators and other critical avionics working when the
aircraft systems that power them fail.
Stan Sutterfield
________________________________________________________________________________
| Subject: | Fuel Pump - dual switching |
| From: | "leckers" <leckers(at)free.fr> |
I have the original panel mounted switch for the fuel pump on my Glasair - simple
'on/off'. On the copilot side I have the stock stick and only a single PTT
on the grip. On the pilot side, I have JD's Infinity grip with one of the switches
(at present it is a simple on/off) ear-marked to also operate the fuel pump.
I need to retain the panel switch capability so the copilot can operate the
pump if (s)he is flying.
My thoughts were along the lines of a switching system like the staircase example
of a switch at top and bottom being able to turn on or off the light from either
position. I would be quite happy to have a warning lamp to indicate the
pump is actually on/running. I need a different type of S700 switch (Which?) on
the panel, and also need to find a smaller equivalent type to fit in JD's grip
- both of which accomplish the necessary internal switching. (I definitely
need assistance with a simple wiring diagram too!). I don't see the necessity
for a relay set-up as I've used for the flaps with a similar scenario - normal
panel switch and JD's toggle switch on pilot's stick grip. I've been through
the chapter in Bob's book on switches a couple of times, but I can't find an applicable
example to help me on this - though it is, I have to say, that I may
be me missing the obvious - "can't see the wood for the trees" etc. etc.
This particular switching scenario must have been resolved many times before, and
I'd be most grateful if a member could point me in the right direction?
--------
IanL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293734#293734
________________________________________________________________________________
| From: | "Bruce Gray" <bgray(at)glasair.org> |
| Subject: | Fuel Pump - dual switching |
Hi Ian,
Check a house wiring book.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
leckers
Sent: Saturday, April 10, 2010 4:35 AM
Subject: AeroElectric-List: Fuel Pump - dual switching
I have the original panel mounted switch for the fuel pump on my Glasair
- simple 'on/off'. On the copilot side I have the stock stick and only a
single PTT on the grip. On the pilot side, I have JD's Infinity grip
with one of the switches (at present it is a simple on/off) ear-marked
to also operate the fuel pump. I need to retain the panel switch
capability so the copilot can operate the pump if (s)he is flying.
My thoughts were along the lines of a switching system like the
staircase example of a switch at top and bottom being able to turn on or
off the light from either position. I would be quite happy to have a
warning lamp to indicate the pump is actually on/running. I need a
different type of S700 switch (Which?) on the panel, and also need to
find a smaller equivalent type to fit in JD's grip - both of which
accomplish the necessary internal switching. (I definitely need
assistance with a simple wiring diagram too!). I don't see the necessity
for a relay set-up as I've used for the flaps with a similar scenario -
normal panel switch and JD's toggle switch on pilot's stick grip. I've
been through the chapter in Bob's book on switches a couple of times,
but I can't find an applicable example to help me on this - though it
is, I have to say, that I may be me missing the obvious - "can't see the
wood for the trees" etc. etc.
This particular switching scenario must have been resolved many times
before, and I'd be most grateful if a member could point me in the right
direction?
--------
IanL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293734#293734
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
| Subject: | Fuel Pump - dual switching |
I have the original panel mounted switch for the fuel pump on my Glasair -
simple 'on/off'. On the copilot side I have the stock stick and only a
single PTT on the grip. On the pilot side, I have JD's Infinity grip with
one of the switches (at present it is a simple on/off) ear-marked to also
operate the fuel pump. I need to retain the panel switch capability so the
copilot can operate the pump if (s)he is flying.
IanL
Here is a simple circuit that requires using 2 single pole
double throw (on - on) switches. Hope this helps a bit.
Roger
________________________________________________________________________________
| From: | "Bill Bradburry" <bbradburry(at)bellsouth.net> |
| Subject: | Fuel Pump - dual switching |
IanL,
I doubt you will find a switch small enough to fit in JDs grip that will
carry the amps necessary for the fuel pump. If you already know how to do
this with a relay, I suggest you go ahead with that method. Or you can
stick a relay in the schematic that was provided by one of the readers.
Bill B
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of leckers
Sent: Saturday, April 10, 2010 4:35 AM
Subject: AeroElectric-List: Fuel Pump - dual switching
I have the original panel mounted switch for the fuel pump on my Glasair -
simple 'on/off'. On the copilot side I have the stock stick and only a
single PTT on the grip. On the pilot side, I have JD's Infinity grip with
one of the switches (at present it is a simple on/off) ear-marked to also
operate the fuel pump. I need to retain the panel switch capability so the
copilot can operate the pump if (s)he is flying.
My thoughts were along the lines of a switching system like the staircase
example of a switch at top and bottom being able to turn on or off the light
from either position. I would be quite happy to have a warning lamp to
indicate the pump is actually on/running. I need a different type of S700
switch (Which?) on the panel, and also need to find a smaller equivalent
type to fit in JD's grip - both of which accomplish the necessary internal
switching. (I definitely need assistance with a simple wiring diagram too!).
I don't see the necessity for a relay set-up as I've used for the flaps with
a similar scenario - normal panel switch and JD's toggle switch on pilot's
stick grip. I've been through the chapter in Bob's book on switches a couple
of times, but I can't find an applicable example to help me on this - though
it is, I have to say, that I may be me missing the obvious - "can't see the
wood for the trees" etc. etc.
This particular switching scenario must have been resolved many times
before, and I'd be most grateful if a member could point me in the right
direction?
--------
IanL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293734#293734
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "rckol" <rckol(at)kaehlers.com> |
Noah,
I don't see any wiring errors.
I am planning to use the same architecture but with a couple of different details
you might consider.
1. I am going to eliminate the two shunts and run both alternator B leads through
one Hall Effect transducer. This eliminates the need to add switching for
the shunts. The AFS manual that I have (about 2 years old) shows provisions for
only one shunt.
2. I am going to use an LR3C regulator instead of the SB1B. With the install kit,
the SB1B is $308 more than the LR3C and the I don't see that the extra features
it has add any value in this application.
You will have a main alt out annunciator light, plus voltage and current reading
on the AFS, plus you can probably program alarms for a low voltage condition
in the AFS, so the automatic turn on feature is not adding any value in my opinion.
You will also be able to read the voltage and standby alt current on the AFS, so
the blinking current warning light is also redundant.
Great features for adding to an old TC aircraft, but you already have their functions
well covered.
Just my 2 cents.
Dick Kaehler
--------
rck
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293761#293761
________________________________________________________________________________
| From: | "B Tomm" <fvalarm(at)rapidnet.net> |
| Subject: | Fuel Pump - dual switching |
While the schematic in the drawing will work, I wouldn't use that
architecture because it will be confusing. Sometimes switch toggle up will
be on and sometimes switch down will be on, depending on the position of the
other switch. That drawing is OK for light switches at home or for
pushbutton latching switches.
I would just wire both switches in parallel so that either one can turn the
pump on, but both must be off to turn pump off. I think this would be best
and satisfy 99% of your flying needs without confusion.
My $.02 worth.
Bevan
> _____________________________________________
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of ROGER
> & JEAN CURTIS
> Sent: Saturday, April 10, 2010 6:47 AM
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Fuel Pump - dual switching
>
>
>
> I have the original panel mounted switch for the fuel pump on my Glasair -
> simple 'on/off'. On the copilot side I have the stock stick and only a
> single PTT on the grip. On the pilot side, I have JD's Infinity grip with
> one of the switches (at present it is a simple on/off) ear-marked to also
> operate the fuel pump. I need to retain the panel switch capability so the
> copilot can operate the pump if (s)he is flying.
> IanL
>
>
> Here is a simple circuit that requires using 2 single pole double
> throw (on - on) switches. Hope this helps a bit.
>
> Roger
>
> << File: Dual switch fuel pump.pdf >>
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
| Subject: | Fuel Pump - dual switching |
While the schematic in the drawing will work, I wouldn't use
that architecture because it will be confusing. Sometimes switch toggle up
will be on and sometimes switch down will be on, depending on the position
of the other switch.
When the light is on the pump is on, flip
either switch and it is off. I personally would not find this confusing.
If up, down is confusing, mount the switch for left, right.
I would just wire both switches in parallel so that either
one can turn the pump on, but both must be off to turn pump off. I think
this would be best and satisfy 99% of your flying needs without confusion.
If both switches are on they must both be
turned off to shut down the pump.
If you are going this route, might I suggest
that you put a switch on the panel within ease reach of either pilot, fewer
parts, fewer single points of failure.
There are other ways of accomplishing this,
but this is simple and will work.
Roger
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "user9253" <fran4sew(at)banyanol.com> |
Noah,
Here are some suggestions for weight savings.
12AWG (or maybe 14) is big enough for the aux alternator and E-Bus.
Have you done a load analysis on the E-Bus, adding the actual amperage of individual
loads (not individual fuse sizes)?
The main power bus feed is not normally protected by a fuse. If you want to, that
is OK. But one ANL60 can protect both the alternator B lead and the main
power bus feed wire from excessive battery current. The alternator can not put
out much more than 60amps, so it is not necessary to use a fuse between the
alternator and main power bus.
6AWG is big enough for the main alternator unless you expect that the aircraft
load will continuously draw 60amps.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293777#293777
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "Noah" <sgninc(at)cox.net> |
rckol wrote:
> Noah,
>
> I don't see any wiring errors.
>
> I am planning to use the same architecture but with a couple of different details
you might consider.
>
> 1. I am going to eliminate the two shunts and run both alternator B leads through
one Hall Effect transducer. This eliminates the need to add switching for
the shunts. The AFS manual that I have (about 2 years old) shows provisions
for only one shunt.
>
> 2. I am going to use an LR3C regulator instead of the SB1B. With the install
kit, the SB1B is $308 more than the LR3C and the I don't see that the extra features
it has add any value in this application.
>
> You will have a main alt out annunciator light, plus voltage and current reading
on the AFS, plus you can probably program alarms for a low voltage condition
in the AFS, so the automatic turn on feature is not adding any value in my
opinion.
>
> You will also be able to read the voltage and standby alt current on the AFS,
so the blinking current warning light is also redundant.
>
> Great features for adding to an old TC aircraft, but you already have their functions
well covered.
>
> Just my 2 cents.
>
> Dick Kaehler
Appreciate the comments Dick.
#1 is a good idea. I actually meant to show a 2nd hall effect sensor on the aux
B-Lead vice a shunt. You're right that AFS does not have provision for two
shunts, but they do have provision for a shunt and a HE sensor. I have struggled
with how much instrumentation on current is enough or too much. I debated
having a single current sensor at the battery ground cable. AFS' software can
not presently deal with negative current flow signals (battery charging) so
this is why I ended up with this configuration. Never thought of having two alternator
B-Leads going thru one HE sensor. I like this. But if you have two
LR3 regulators, doesn't that mean they will both be online simultaneously (load
sharing)? Or are you dialing the voltage setting down on one of them so that
it only comes alive in case of failure of the primary? Or, are you keeping
the aux alternator field switch normally open, and only switching the aux alt
on in case of primary alt failure?
One thing I should have mentioned is that standard operating procedure is to have
both bus switches in the full on position during flight (both alternators available).
One thing I like about this is that no pilot action is required in
case of a primary alternator failure - the aux alternator just comes online and
no switching is immediately required. You might want to eventually turn off
the main bus / battery contactor depending on loads.
Anyway, some thought provoking comments so thank you.
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293779#293779
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "Noah" <sgninc(at)cox.net> |
user9253 wrote:
> Noah,
> Here are some suggestions for weight savings.
> 12AWG (or maybe 14) is big enough for the aux alternator and E-Bus.
> Have you done a load analysis on the E-Bus, adding the actual amperage of individual
loads (not individual fuse sizes)?
> The main power bus feed is not normally protected by a fuse. If you want to,
that is OK. But one ANL60 can protect both the alternator B lead and the main
power bus feed wire from excessive battery current. The alternator can not
put out much more than 60amps, so it is not necessary to use a fuse between the
alternator and main power bus.
> 6AWG is big enough for the main alternator unless you expect that the aircraft
load will continuously draw 60amps.
> Joe
Thanks for the input, Joe.
I am in process of sizing wires, fuses, and breakers so what is listed is preliminary.
I was under the impression that separate ANL fuses were used on both the B-lead
and the bus feed so that a short in either would not take down the other?
Although now that I think about it some more, if configured as you indicate, a
significant enough fault in either the primary B-lead or main bus feed would open
the single ANL fuse, which would take both the primary alternator and the
main bus offline. But the E-bus would not be affected, so maybe this is a good
trade off. Those ANL carriers ARE large and heavy. Why bother carrying the
weight?
I'm gonna have to sleep on this one.
Thanks again for your comments Joe.
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293783#293783
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Peer Review of Schematic |
>
> > What drove the decision to use an SD-20 in lieu
> > of the lighter and much less expensive SD-8?
> >
> > Bob . . .
>
>
>Bob, didn't we already hash these questions out?
Sorry. I have so many conversations going I have trouble
keeping track of them. Ignore all the above.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "Noah" <sgninc(at)cox.net> |
I should have posted some notes along with the schematic. Most have been covered.
One that has not involves the E-bus feed diode. I selected a Power Schottky
from Ixys. Cheapest outlet I found was Future Electronics:
http://ixdev.ixys.com/DataSheet/l227.pdf
The forward voltage drop for this diode is quite low, 0.29V at 20A, so the power
dissipated is also low, only
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293786#293786
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "user9253" <fran4sew(at)banyanol.com> |
Noah,
You pointed out a good reason not to connect the main power bus to the same
fuse as the alternator. I do not think that any of the Z-drawings have a fuse
in the wire supplying power to the main bus. The theory is that a short circuit
in the wire will burn away the aluminum sheet metal and thus electrically
isolate the heavy copper wire once again. If you do a good job of wiring, and
I am sure you will, then the likelihood of a short circuit is remote, especially
if the wire is double insulated where it passes through the firewall or bulkheads.
The main purpose of the ANL fuse is to protect the battery and wires in case
the alternator shorts out (a rare occurrence). But if it does short out, one
would not want 400 amps draining the battery and heating wires.
> Second, to reduce current (and therefore overall voltage drop) across the diode(s).
That is true, but not by a significant amount. Diode redundancy and heat dissipation
are good reasons for using both diodes in the package, IMHO. Heat conducting
grease should be used between the diode and heatsink.
I do not see a problem with always having the E-bus alternate feed turned on.
You might consider having the aux-alternator on a separate switch so that you
can control it independently of the E-bus. If I remember correctly, Bob N.
said that connecting two alternators in parallel causes problems unless the voltage
regulator for the aux unit is set well below the set point of the main alternator.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293788#293788
________________________________________________________________________________
| Subject: | Re: Peer Review of Schematic |
| From: | "rckol" <rckol(at)kaehlers.com> |
Noah,
If you use an LR3C instead of the SB1B, the normal operating condition would be
with the Aux alternator and alt battery feed off. You would be feeding the E-bus
through the diode under normal conditions.
With your scheme using the SB1B and the associated switch always on, I think your
E-bus would end up getting most of its power back through the relay, since
that will be the lower resistance path. I don't think the diode would be doing
much of anything unless the main contactor is on and the alt-feed relay is
off.
I think the auto-on feature of the SB1B would be a great thing on an aircraft with
a volt or ammeter stuck down on the bottom of the panel where you might not
notice the problem until it manifested itself after the battery had run down
and the gizmos started going on the fritz. I heard one such first hand dark
and stormy night story from my CFII. With all the low voltage signaling you
have, I would personally not be worried about missing the event or having to throw
the switch(s).
Dick
--------
rck
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293800#293800
________________________________________________________________________________
| From: | Phil <philwhite9(at)aol.com> |
| Subject: | Crowbar OV module part |
Bob: The part listed as "MBS4991" is no longer carried by Digi-Key.
Mouser lists a possible replacement as a silicon bi-lateral switch by
NTE as their part NTE6403. Is this the correct type item? Or is that
device something else?
Need to build 2 OV modules for my electrically dependent, dual
alternator project.
Phil
RV-10 w/ Mazda 20B rotary engine in IL
________________________________________________________________________________
| Subject: | Re: HLMP-2685 multi-LEDs off LR3C |
| From: | James Kilford <james(at)etravel.org> |
Bob,
That's great, thank you. It gives me a good place from which to experiment.
James
On Thu, Apr 8, 2010 at 2:04 PM, Robert L. Nuckolls, III
wrote:
>
>
>
>>
>>
>> http://parts.digikey.com/1/parts/681506-led-lt-bar-hi-eff-red-8led-dip-hlmp2685.html
>>
>> I'd like to hook one of these to the LR3C regulator instead of the
>> supplied filament lamp, so that it can go into the annunciator panel
>> too.
>>
>> I've been trying to trace a schematic of Bob's, which I'm sure I've
>> seen, of how to use an LED instead of a filament lamp with the LR3C,
>> as a starting point. I can't find it, and the resistor values would
>> be different in any case, so can anyone throw any light on to how to
>> use one of these 8-LED devices with the LR3C?
>
> The schematic I published is at:
>
> http://aeroelectric.com/Pictures/Schematics/LR3_LV_Led_1.jpg
>
> Your application will take some experimentation.
> You can try paralleling all the LEDs and seeing how
> well you can excite the array and still have uniform
> illumination. You may find that you need to treat
> them as separate LEDs.
>
> Just be aware that LR3 lamp driver is never completely
> "OFF". The off current is too low to get any light
> from a bulb but it will cause an LED to glow at a
> reduced intensity. Hence the paralleling resistor to
> get the LED to mimic a lamp more closely.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Crowbar OV module part |
At 04:57 AM 4/11/2010, you wrote:
>
>Bob: The part listed as "MBS4991" is no longer carried by Digi-Key.
>Mouser lists a possible replacement as a silicon bi-lateral switch
>by NTE as their part NTE6403. Is this the correct type item? Or is
>that device something else?
>
> Need to build 2 OV modules for my electrically dependent, dual
> alternator project.
Those devices have been out of production for
many years. We purchased one-time-lifetime-buys
to keep our production needs at B&C/AEC going
but developed the 2-transistor synthetic trigger
diode version illustrated in the DIY data package
for when they finally run out.
Suggest you consider that version for your project.
I'm aware of no suitable replacements for the MBS4991/4992
component.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Lithium backup power |
At 08:46 PM 4/9/2010, you wrote:
>Bob,
>You've probably already heard about this. Any comments?
>
>The huge advancements in lithium battery technology that have
>improved consumer products ranging from cell phones and laptop
>computers to electric cars will soon arrive in aircraft.
>Mid-Continent Instruments recently certified an emergency power
>supply known as the MD835, which is designed to keep electric
>attitude indicators and other critical avionics working when the
>aircraft systems that power them fail.
>
>Stan Sutterfield
>
Sure. Li-Ion has been taking hold in emergency back-up
batteries for some years. They're particularly well
suited to situations that do not call for humongous
discharge (cranking) and charge (dual 600A generators)
currents.
A couple years ago I evaluated the 7V Li-Ion cartridges
from one of the famous hand-tool manufacturers . . . pretty
good batteries but still a pain in the arse for doing
a graceful system integration.
My personal design goals will continue to move forward
with the notion that it's better to build a failure-tolerant
system than patch on emergency back-up band-aids. The
artfully crafted, maintained and operated system will not
experience an emergency.
Bob . . .
________________________________________________________________________________
| Subject: | intermittent transponder mystery solved |
| From: | Bill Boyd <sportav8r(at)gmail.com> |
I finally ran to ground my transponder intermittent that has been plaguing
me for years! My set-up is a Garmin GTX 320 in a tray that formerly housed
a Narco AT-150, using Garmin's plug-and-play adapter to fit between the two.
The first time it crapped-out, I sent the transponder back to Garmin: $250
bench fee to be told the box is fine. Worked fine for awhile after that.
Then it started becoming intermittent - the interrogation light would
flicker normally at the start of a cross-country, and ATC could give me VFR
advisory service, but often by the time I got to the destination I was only
showing as a primary target on radar.
I limped along like this for awhile, but the prospect of having to enter the
Orlando mode C veil next week with "known issues" motivated me to try again.
I started with what has worked before - removing the transponder and
adapter tray, spraying every connection with contact cleaner and
reassembling it all. Well, that worked for a few seconds and then it quit
again, so I got out the continuity checker and started checking the RF path
for opens and shorts. The meter showed an open on the coax center conductor
when I wiggled it in the back of thel Narco tray. Put the innards back in,
and sure enough, if I held the coax a certain way, I saw interrogation
flashes; if I let go, it stopped. Now all I need is for the pax to reach
under the panel and hold the coax the whole trip. Not happening.
The BNC jack on the transponder itself looked good; the male mating plug on
the front side of the adapter looked good - no bent pin. The female jack in
the back of the Garmin-to-Narco adapter looked good. There is a small
length of RG-184-type teflon coax inside the adapter, but it is totally
protected inside the chassis and is under no mechanical strain, and it's new
Garmin manufacture, so the problem can't be there so the
fault must be in that ancient RG-58 pigtail that came with the Narco tray
and was probably soldered in the 1950's. But the continuity checker showed
no opens or shorts no matter how I wiggled it on the bench, and its coax
shield is well-crimped and fully strain-relieved. Maybe the male pin on the
end of that pigtail, the one that's captive in the back of the tray, is
worn/undersize. So I added a thin layer of solder to the gold pin and
pressed it back into the fitting on the Garmin adapter tray - still showed
an intermittent open when I wiggled it! @#$%!
At this point, I noticed that as I twisted the jack into the plug, the shell
of the Garmin female (the barrel) would move with it. That's not supposed
to happen. In fact, the entire guts of the Garmin female fitting is threaded
into its mounting flange, and since it is not secured or safetied in any way
(and was doubtless under-torqued at assembly), movement of the male coax
pigtail on the outside of the tray eventually broke the BNC solder
connection inside the Garmin adapter. I re-threaded the outer shell of the
Garmin adapter's female connector with red LocTite and re-soldered the
mini-coax to it. Problem fixed - hopefully for good!
Moral of the story: never assume that a factory avionics assembly is
properly done, or that a wire that "can't possibly" move/break hasn't done
just that. I only wish that there was some lifetime warranty where the
Garmin would comp me for the time and aggravation this has caused.
I'm attaching pictures that show the adapter tray, the fitting as it comes
apart but isn't supposed to, and how it broke the solder joint internally.
The last one shows the guts of the BNC fitting completely unscrewed from
its mounting flange and the coax just hanging there. May this never happen
to you! :-) If it does, remember to question everything you're assuming.
I'm gonna feel bad if the pictures don't upload - never done that on
Matronics list before.
-Bill B. / "Stormy" RV-6A
________________________________________________________________________________
| From: | "David LLoyd" <skywagon(at)charter.net> |
| Subject: | Re: intermittent transponder mystery solved |
Bill,
If you reach the right service engineer at Garmin, repeat the story, I
am sure that they would be happy to compensate you and also return the
$250 left on their table. I have had issues with Garmin several times
in the past, and when the story was told, they were gracious about
working with me. Unless things have changed at Garmin, I would take
your service problem back to them. They may have an assembly problem or
Q/C problem and would want to know about it...... Shouldn't matter if
the unit is out of warranty....
If you don't have luck with your first try at the refund, review their
management team via the web and write the key guy a detailed letter....
he will make it happen....
David
-------------------------------------------------------------------------
-------
----- Original Message -----
From: Bill Boyd
To: rvsoutheast-list(at)matronics.com ; aeroelectric-list(at)matronics.com
Sent: Sunday, April 11, 2010 7:15 PM
Subject: AeroElectric-List: intermittent transponder mystery solved
I finally ran to ground my transponder intermittent that has been
plaguing me for years! My set-up is a Garmin GTX 320 in a tray that
formerly housed a Narco AT-150, using Garmin's plug-and-play adapter to
fit between the two. The first time it crapped-out, I sent the
transponder back to Garmin: $250 bench fee to be told the box is fine.
Worked fine for awhile after that. Then it started becoming
intermittent - the interrogation light would flicker normally at the
start of a cross-country, and ATC could give me VFR advisory service,
but often by the time I got to the destination I was only showing as a
primary target on radar.
I limped along like this for awhile, but the prospect of having to
enter the Orlando mode C veil next week with "known issues" motivated me
to try again. I started with what has worked before - removing the
transponder and adapter tray, spraying every connection with contact
cleaner and reassembling it all. Well, that worked for a few seconds
and then it quit again, so I got out the continuity checker and started
checking the RF path for opens and shorts. The meter showed an open on
the coax center conductor when I wiggled it in the back of thel Narco
tray. Put the innards back in, and sure enough, if I held the coax a
certain way, I saw interrogation flashes; if I let go, it stopped. Now
all I need is for the pax to reach under the panel and hold the coax the
whole trip. Not happening.
The BNC jack on the transponder itself looked good; the male mating
plug on the front side of the adapter looked good - no bent pin. The
female jack in the back of the Garmin-to-Narco adapter looked good.
There is a small length of RG-184-type teflon coax inside the adapter,
but it is totally protected inside the chassis and is under no
mechanical strain, and it's new Garmin manufacture, so the problem can't
be there so the fault must be in that ancient RG-58
pigtail that came with the Narco tray and was probably soldered in the
1950's. But the continuity checker showed no opens or shorts no matter
how I wiggled it on the bench, and its coax shield is well-crimped and
fully strain-relieved. Maybe the male pin on the end of that pigtail,
the one that's captive in the back of the tray, is worn/undersize. So I
added a thin layer of solder to the gold pin and pressed it back into
the fitting on the Garmin adapter tray - still showed an intermittent
open when I wiggled it! @#$%!
At this point, I noticed that as I twisted the jack into the plug, the
shell of the Garmin female (the barrel) would move with it. That's not
supposed to happen. In fact, the entire guts of the Garmin female
fitting is threaded into its mounting flange, and since it is not
secured or safetied in any way (and was doubtless under-torqued at
assembly), movement of the male coax pigtail on the outside of the tray
eventually broke the BNC solder connection inside the Garmin adapter. I
re-threaded the outer shell of the Garmin adapter's female connector
with red LocTite and re-soldered the mini-coax to it. Problem fixed -
hopefully for good!
Moral of the story: never assume that a factory avionics assembly is
properly done, or that a wire that "can't possibly" move/break hasn't
done just that. I only wish that there was some lifetime warranty where
the Garmin would comp me for the time and aggravation this has caused.
I'm attaching pictures that show the adapter tray, the fitting as it
comes apart but isn't supposed to, and how it broke the solder joint
internally. The last one shows the guts of the BNC fitting completely
unscrewed from its mounting flange and the coax just hanging there. May
this never happen to you! :-) If it does, remember to question
everything you're assuming.
I'm gonna feel bad if the pictures don't upload - never done that on
Matronics list before.
-Bill B. / "Stormy" RV-6A
________________________________________________________________________________
| Subject: | Re: Delete if you wish, but this is funny! |
| From: | "donjohnston" <don(at)numa.aero> |
This is a "cover" (almost verbatim) of the Retro Encabulator. Maybe because I saw
it first, I think the Rockwell product is a better presentation.
http://video.google.com/videoplay?docid=5125780462773187994#
-Don
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293929#293929
________________________________________________________________________________
| Subject: | Re: Fuel Pump - dual switching |
| From: | "leckers" <leckers(at)free.fr> |
Really sorry, but I cannot open either of the .dat files to see the diagram.....
Clues? I use Windows 7. Thanks for the suggestions.
--------
IanL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293931#293931
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
| Subject: | Re: Fuel Pump - dual switching |
Really sorry, but I cannot open either of the .dat files to see the
diagram..... Clues? I use Windows 7. Thanks for the suggestions.
--------
IanL
Go to (get.adobe.com) and download the reader. This will
allow you to open the [Dual switch fuel pump.pdf] file attached.
Roger
________________________________________________________________________________
| Subject: | Re: Fuel Pump - dual switching |
| From: | "leckers" <leckers(at)free.fr> |
Roger - adobe reader will NOT open the file that is in this forum as winmail.dat.
There is no attachment file that I can see in pdf format.
Any chance you could try direct to me ianleckenby(at)yahoo.co.uk? Thanks.
--------
IanL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=293958#293958
________________________________________________________________________________
| From: | Valin & Allyson Thorn <thorn(at)starflight.aero> |
> Bob,
>
> After a lot of business travel I=99m getting back to our
airplane=99s
> electrical system design. As a reminder, we=99re building a
Lancair L
> egacy =93 a small very weight sensitive airplane (explaining why
> we=99re not going with dual alt dual batt). We have the engine
(IO-55
> 0N) and it has a big 100A alternator (all electric air conditioning)
> and B&C=99s little 20A alternator on a vacuum pump pad.
We=99re
> planning on your Z-12 power architecture =93 but, first I=99
d like to
> explore a variation.
>
> As you know, in your Z-12 with the SB1B voltage regulator, the
> auxiliary alternator does not come online unless the main alternator
> is overloaded or off. It would be nice to have the 20A alternator
> contribute to the electrical power generation during normal
> operation. Could I use two normal B&C voltage regulators (LR3Cs)
> with the 20A alternator voltage regulator set at 28V while the
> voltage regulator for the 100A alternator is set at 26V so that the
> first 20 Amps of load are handled by the little Alt and the big Alt
> gets the rest of the load? Would there be any instabilities between
> the two voltage regulators?
>
> I like that in the worst load conditions =93 like taxiing out on
a hot
> day with the electric A/C on =93 that the big Alt would be 20A
lower
> and cooler, maybe extending it's life.
>
> What do you think?
>
> Thanks,
>
> Valin Thorn
>
> Lancair Legacy Project
>
>
________________________________________________________________________________
| From: | "edleg" <ed_legault(at)yahoo.com> |
Your kidding,... right? A "very small, weight sensitive" airplane with a 550 engine,
air conditioning, all electric....
jeeshh
[Rolling Eyes]
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294070#294070
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
At 03:39 PM 4/12/2010, you wrote:
Bob,
After a lot of business travel Im getting back
to our airplanes electrical system design. As
a reminder, were building a Lancair Legacy a
small very weight sensitive airplane (explaining
why were not going with dual alt dual
batt). We have the engine (IO-550N) and it has a
big 100A alternator (all electric air
conditioning) and B&Cs little 20A alternator
on a vacuum pump pad. Were planning on your
Z-12 power architecture but, first Id like to explore a variation.
As you know, in your Z-12 with the SB1B voltage
regulator, the auxiliary alternator does not come
online unless the main alternator is overloaded
or off. It would be nice to have the 20A
alternator contribute to the electrical power
generation during normal operation. Could I use
two normal B&C voltage regulators (LR3Cs) with
the 20A alternator voltage regulator set at 28V
while the voltage regulator for the 100A
alternator is set at 26V so that the first 20
Amps of load are handled by the little Alt and
the big Alt gets the rest of the load? Would
there be any instabilities between the two voltage regulators?
You could use two LR3 as you suggest but the SD-20
driven from the vacuum pump pad is not capable
of significant output during taxi operations.
This is why it's a "standby" alternator as opposed to
an "auxiliary" alternator. It's capable of rated
performance only in flight.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: intermittent transponder mystery solved |
>I'm attaching pictures that show the adapter tray, the fitting as it
>comes apart but isn't supposed to, and how it broke the solder joint
>internally. The last one shows the guts of the BNC fitting
>completely unscrewed from its mounting flange and the coax just
>hanging there. May this never happen to you! :-) If it does,
>remember to question everything you're assuming.
>
>I'm gonna feel bad if the pictures don't upload - never done that
>on Matronics list before.
Good work! That itty-bitty coax has been problematic
when it comes to durability of soldered joints.
As you've discovered, the center-conductor is
pretty skinny.
Bob . . .
________________________________________________________________________________
Wow,
The Legacy is already CG sensitive with the big motor, then you install
the air-conditioning stuff which moves the CG aft and you've stopped the
big guys from sweating so they're no longer losing weight which makes
the plane more sensitive to gross weight when you fill up the 32.5 gal
fuel tanks. Now, you either need more power or you need to buy a 40 amp
alternator to save 4 pounds so you can carry a change of clothes for the
weekend. To save more weight I'd install the SD-8 and when #1 goes
south, shut down the air-conditioning, turn out all the lights and run
home on a 1 amp Dynon. When the 100 amp job goes you'll be sweating
bullets anyway so the air-conditioning will simply become camping gear
at that point.
That said, I really do enjoy the Legacy.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of edleg
Sent: Tuesday, April 13, 2010 10:43 AM
Subject: AeroElectric-List: Re: Z-12 Twist?
Your kidding,... right? A "very small, weight sensitive" airplane with a
550 engine, air conditioning, all electric....
jeeshh
[Rolling Eyes]
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294070#294070
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | copper foil groundplane |
Hi guys=2C
I've just joined this group and have a couple of questions. I have searc
hed the archives=2C but finding my particular answers is tough=2C to say th
e least.
I'm getting very close to installing the Icom A200 comm antenna in my tub
e & fabric airplane (Kolb MkIII). I think I've chosen to go underneath the
fuselage=2C between the main gear legs=2C with the 23" steel rod mast poin
ting down and rearward.
Here's my first question=3B is the center solid wire RG58 antenna lead the
one that point down and away? In other words=2C the shielding cable is th
e lead that I make the groundplane with=2C right? I also assume they are N
OT interchangeable=2C true?
I can build a decent dipole antenna using a 1/8" welding rod using Dean S
cott's design plans. But=2C the groundplane rod of the dipole would be ins
ide the steel frame fuselage=2C which isn't good. I would include the Paws
ey stub for the balun.
Second question=3B can I build a 1/2" copper tape "X" groundplane and at
tach it to the inside of the fabric at the center of the BNC connector. If
it's possible to use this style of groundplane with the solid rod antenna
=2C can a guy use 6 legs of the copper foil? Any advantage to more than ju
st the (4) 23" strips?
Thanks for your help!
Mike Welch
PS. Here is the link to Dean Scott's antenna design I would probably be us
ing.
http://forums.matronics.com//files/antenna_design_118.pdf
_________________________________________________________________
Hotmail is redefining busy with tools for the New Busy. Get more from your
inbox.
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________________________________________________________________________________
| From: | Doug Ilg <doug.ilg(at)verizon.net> |
| Subject: | Re: copper foil groundplane |
Mike,=0A=0AHave you looked at Miracle Antenna's Air Whip?- http://www.mir
acleantenna.com/AirWhip.htm- It's a full dipole antenna that's made compl
etely of flexible wire.- It's also end-fed, so you don't need access to t
he middle of the antenna for connection.- You can put it anywhere in the
fuselage that's not shielded by conductive parts.=0A=0AI'm not flying yet,
but mine seems to work very well on the ground.- It fits quite well in th
e fiberglass nose cone of my Challenger.- Based on a quick look at a pict
ure of a Kolb M3X, I'd guess you could do something similar in your airplan
e.- It might save you some of the hassle you're dealing with.=0A=0AFYI.
=0A=0A--- --- --- --- -Doug=0A-=0ADoug Ilg=0AGrum
man Tiger N74818, College Park-Airport (KCGS), Maryland=0AChallenger II L
SS LW (N641LG-reserved)-- kit underway at Laurel Suburban (W18)=0A=0A
-=0A=0A=0A>=0A>From: Mike Welch <mdnanwelch7(at)hotmail.com>=0A>To: aeroelec
tric-list(at)matronics.com=0A>Sent: Tue, April 13, 2010 1:15:25 PM=0A>Subject:
AeroElectric-List: copper foil groundplane=0A>=0A>Hi guys,=0A>-=0A>- I
've just joined this group and have a couple of questions.- I have search
ed the archives, but finding my particular answers is tough, to say the lea
st.=0A>-=0A>- I'm getting very close to installing the Icom A200 comm a
ntenna in my tube & fabric airplane (Kolb MkIII).- I think I've chosen to
go underneath the fuselage, between the main gear legs, with the 23" steel
rod mast pointing down and rearward.--=0A>-=0A>
________________________________________________________________________________
| Subject: | Re: intermittent transponder mystery solved |
| From: | Bill Boyd <sportav8r(at)gmail.com> |
Actually, Bob, under 10x loupe examination of the coax and the center
terminal of the fitting, there was no visual indication that there had been
an actual joint there to fracture - just solder on each, and no impression
of the conductor in the little puddle on the coax fitting. But you can bet
there is, now! There was no need to re-trim the coax to prepare it for
re-soldering - all the wire was still there.
-Bill
On Tue, Apr 13, 2010 at 11:39 AM, Robert L. Nuckolls, III <
nuckolls.bob(at)aeroelectric.com> wrote:
> nuckolls.bob(at)aeroelectric.com>
>
>
> I'm attaching pictures that show the adapter tray, the fitting as it comes
>> apart but isn't supposed to, and how it broke the solder joint internally.
>> The last one shows the guts of the BNC fitting completely unscrewed from
>> its mounting flange and the coax just hanging there. May this never happen
>> to you! :-) If it does, remember to question everything you're assuming.
>>
>> I'm gonna feel bad if the pictures don't upload - never done that on
>> Matronics list before.
>>
>
> Good work! That itty-bitty coax has been problematic
> when it comes to durability of soldered joints.
> As you've discovered, the center-conductor is
> pretty skinny.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | copper foil groundplane |
Doug=2C
No=2C I hadn't heard of this one. It sounds like this could be the perfe
ct setup. Do you know how the wire is "oriented"? Can you just make a cir
cular loop=2C or ????
I do like the idea of this antenna=2C but since I'm between jobs right no
w=2C funds are very scarce. Plus=2C I really wanted to make the antenna fo
r my plane=2C just for the experience.
Does anyone know of a DIY plan for this type of dipole end-fed com antenn
a? What is in that little black box? (hopefully not some of that "special
smoke" that leaks out when you touch two wrong wires together!!)
If anyone knows of a way to make one these single wire dipole end-fed ant
ennas=2C I'd sure appreciate a drawing or two.
Thanks again=2C Doug=2C for the tip!!
Mike Welch
Mike=2C
Have you looked at Miracle Antenna's Air Whip? http://www.miracleantenna.c
om/AirWhip.htm It's a full dipole antenna that's made completely of flexib
le wire. It's also end-fed=2C so you don't need access to the middle of th
e antenna for connection. You can put it anywhere in the fuselage that's n
ot shielded by conductive parts.
I'm not flying yet=2C but mine seems to work very well on the ground. It f
its quite well in the fiberglass nose cone of my Challenger. Based on a qu
ick look at a picture of a Kolb M3X=2C I'd guess you could do something sim
ilar in your airplane. It might save you some of the hassle you're dealing
with.
FYI.
-Doug
Doug Ilg
Grumman Tiger N74818=2C College Park Airport (KCGS)=2C Maryland
Challenger II LSS LW (N641LG reserved) - kit underway at Laurel Suburban (W
18)
From: Mike Welch <mdnanwelch7(at)hotmail.com>
Sent: Tue=2C April 13=2C 2010 1:15:25 PM
Subject: AeroElectric-List: copper foil groundplane
Hi guys=2C
I've just joined this group and have a couple of questions. I have searc
hed the archives=2C but finding my particular answers is tough=2C to say th
e least.
I'm getting very close to installing the Icom A200 comm antenna in my tub
e & fabric airplane (Kolb MkIII). I think I've chosen to go underneath the
fuselage=2C between the main gear legs=2C with the 23" steel rod mast poin
ting down and rearward.
_________________________________________________________________
Hotmail is redefining busy with tools for the New Busy. Get more from your
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________________________________________________________________________________
| From: | Doug Ilg <doug.ilg(at)verizon.net> |
| Subject: | schematic for a Challenger II |
Folks,
Attached is my schematic diagram for the power distribution in my Challenger II
as a 300 dpi .jpg. I tried to send a .sch file from ExpressSCH, but the list
software refused it.
Anyway, I started with Z-17, but had to change a few things to accommodate the
fuel injection system. This is for a Hirth 3203.
A few notes:
* Pay no attention to wire sizes. I have not really done that analysis. As a
general rule, though, I plan to use 20 AWG for most things, with 4 AWG welding
cable for the fat wires.
* The Hirth lighting coil is good for about 250W, which is about 21A @ 12V.
* The switch logic for the small (1.7Ah) backup battery is pretty much as suggested
by MGL (the EFIS' manufacturer). I combined it with the power for the radio
and EFIS, to save space. I plan to wire it so down is off, middle is backup
power and up is ship's power. In the up position, the EFIS will charge the
battery. The middle position is really only to check that the battery is working.
* The transponder has a built-in power switch, so it was not ganged with the others.
* The EFIS contains low-voltage warning alert.
* The main battery will be an Odyssey PC625, 16Ah.
* I'll add a filter cap on the VR output, if it becomes necessary.
I think that covers it. Now, I'll sit back and watch the fireworks!
Thanks for checking it out.
-Doug
Doug Ilg
Grumman Tiger N74818, College Park Airport (KCGS), Maryland
Challenger II LSS LW (N641LG reserved) - kit underway at Laurel Suburban (W18)
________________________________________________________________________________
| From: | "Valin & Allyson Thorn" <thorn(at)starflight.aero> |
Ed,
Yea, the Lancair Legacy is certainly not a Piper Cub. The weight
sensitivity I'm talking about is because the Legacy was designed for a 1500
lb empty weight -- but most people's airplanes come in around 1650 lbs and
some even approach 1800 lbs.
Also, I live in hot, humid, Houston so have added 40 lbs for an air
conditioner. I have made the A/C unit easily removable, though, for
winters or when payload is more important than comfort. I'm looking to
make up the weight in other areas. Adding a second battery of around 8 AHr
adds about 15 lbs more. I took about 17 lbs out with an MT propeller vs.
the Hartzell.
Valin
Your kidding,... right? A "very small, weight sensitive" airplane with a 550
engine, air conditioning, all electric....
jeeshh
[Rolling Eyes]
________________________________________________________________________________
| From: | "Valin & Allyson Thorn" <thorn(at)starflight.aero> |
Okay, so I shouldn't have to worry about an instability with the two
controllers as long as there's enough difference in their voltage set
points. Good point that the SD-20 only makes rated power at cruise rpms.
Does anyone know of an "auxiliary alternator" candidate that will fit on an
IO-550's vacuum pump pad that has a 1.5 turn ratio to the crankshaft?
Thanks,
Valin
You could use two LR3 as you suggest but the SD-20
driven from the vacuum pump pad is not capable
of significant output during taxi operations.
This is why it's a "standby" alternator as opposed to
an "auxiliary" alternator. It's capable of rated
performance only in flight.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: copper foil groundplane |
At 01:15 PM 4/13/2010, you wrote:
Mike,
Have you looked at Miracle Antenna's Air
Whip? http://www.miracleantenna.com/AirWhip.htm It's a full dipole
antenna that's made completely of flexible wire. It's also end-fed,
so you don't need access to the middle of the antenna for
connection. You can put it anywhere in the fuselage that's not
shielded by conductive parts.
I'm not flying yet, but mine seems to work very well on the
ground. It fits quite well in the fiberglass nose cone of my
Challenger. Based on a quick look at a picture of a Kolb M3X, I'd
guess you could do something similar in your airplane. It might save
you some of the hassle you're dealing with.
The end-fed half-wave antenna has been around
for a long time and is a popular topic of
discussion and debate in the amateur radio
antenna forums. There's a particularly lucid
study of these beasties to be found at:
http://www.aa5tb.com/efha.html
Of course, this article is dealing with the lower
HF frequencies of interest to amateurs but the
physics scales nicely into the higher VHF range.
My sense is that while they can be "tuned" to
accommodate effects of installation, they're not
your grandpa's plug-n-play buggy whip. It's unlikely
that an end-fed half-wave stuck inside the fuselage
of a composite aircraft will be optimized out of the
box for that particular installation.
Having said that, we also know that antenna efficiency
in airplanes can be all over the map and still provide
satisfactory performance. I have no doubt that the
antenna offered has many "satisfied" users.
If the builder is not DIY shy, a few dollars in
materials can be crafted into an quarter-wave
over ground-plane antenna that will certainly
perform as well with more predictable results
for SWR. Getting to the center of a half-wave
dipole isn't hard if you put the center
half way up on the side of the fuselage and
wrap around the inside surface.
Distorting from a straight antenna will have
the effect of electrically lengthening the
antenna so trimming after installation with
some form of SWR instrument would be useful
. . . but probably wouldn't produce observable
differences in performance
I've just joined this group and have a couple of questions.
I have searched the archives, but finding my particular
answers is tough, to say the least. I'm getting very close to
installing the Icom A200 comm antenna in my tube & fabric
airplane (Kolb MkIII). I think I've chosen to go underneath
the fuselage, between the main gear legs, with the 23" steel
rod mast pointing down and rearward.
That will probably work as well as anything else.
You can ground the feedline shield to the steel-tube
structure.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
At 08:13 PM 4/13/2010, you wrote:
>Okay, so I shouldnt have to worry about an
>instability with the two controllers as long as
>theres enough difference in their voltage set
>points Good point that the SD-20 only makes rated power at cruise rpms.
>
>Does anyone know of an auxiliary alternator
>candidate that will fit on an IO-550s vacuum
>pump pad that has a 1.5 turn ratio to the crankshaft?
The problem is drive speed. Most alternators with
automotive pedigrees have a 4000 rpm for full output
with maximum efficiency at about 6000 rpm. George
Braly has another AND2000 pad driven alternator
and claims 30A max output . . . but that too will
be at cruise RPM . . . and I think he gets there by
over-exciting the field by several volts.
Bob . . .
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | RE: copper foil groundplane |
Hi Bob=2C
Thanks for the detailed and informative response. Yes=2C I am very much
a DIY person.
I don't really have the $100 for the Miracle antenna (end-fed halfwave dipo
le)=2C so I guess I'll have to stick with a homemade one.
So far=2C I'm still leaning toward the belly mount dipole=2C and making a
spoke style grid of copper foil=2C where the steel rod mast mounts in the
center of the grid. I'll sure to get a good ground of the groundplane to t
he tube frame.
Does more than four legs of a cu foil groundplane make it better? Or=2C
is that just a waste of copper tape?
I'm curious. After I get this antenna constructed=2C mounted and finishe
d=2C how does one check it's adjustment with a SWR meter. I mean=2C there
aren't many things you could do to the mast=2C except cut off a little. Bu
t=2C what if you cut off too much?
Could you possibly explain the actual nuts and bolts of using an SWR mete
r=2C and how it can allow a guy to improve his antenna's performance?
One more thing.... I am also building a GlaStar=2C and bought the factor
y copper foil dipole antenna. I noticed it has triax cable=2C rather than
regular RG58. I assume this is because the extra layer of the triax acts a
s a balun. I meant to check out how the triax connects at the junction of
the two copper strips=2C but forgot=2C and mounted it in the tail and close
d it up.
For fiberglass airplanes that might use this type of "triax cable copper
foil dipole"=2C how and where is the triax soldered=2C if it's soldered at
all?
Thanks a lot!!
Mike Welch
The end-fed half-wave antenna has been around
for a long time and is a popular topic of
discussion and debate in the amateur radio
antenna forums. There's a particularly lucid
study of these beasties to be found at:
http://www.aa5tb.com/efha.html
Of course=2C this article is dealing with the lower
HF frequencies of interest to amateurs but the
physics scales nicely into the higher VHF range.
My sense is that while they can be "tuned" to
accommodate effects of installation=2C they're not
your grandpa's plug-n-play buggy whip. It's unlikely
that an end-fed half-wave stuck inside the fuselage
of a composite aircraft will be optimized out of the
box for that particular installation.
Having said that=2C we also know that antenna efficiency
in airplanes can be all over the map and still provide
satisfactory performance. I have no doubt that the
antenna offered has many "satisfied" users.
If the builder is not DIY shy=2C a few dollars in
materials can be crafted into an quarter-wave
over ground-plane antenna that will certainly
perform as well with more predictable results
for SWR. Getting to the center of a half-wave
dipole isn't hard if you put the center
half way up on the side of the fuselage and
wrap around the inside surface.
Distorting from a straight antenna will have
the effect of electrically lengthening the
antenna so trimming after installation with
some form of SWR instrument would be useful
. . . but probably wouldn't produce observable
differences in performance
I've just joined this group and have a couple of questions.
I have searched the archives=2C but finding my particular
answers is tough=2C to say the least. I'm getting very close to
installing the Icom A200 comm antenna in my tube & fabric
airplane (Kolb MkIII). I think I've chosen to go underneath
the fuselage=2C between the main gear legs=2C with the 23" steel
rod mast pointing down and rearward.
That will probably work as well as anything else.
You can ground the feedline shield to the steel-tube
structure.
Bob . . .
_________________________________________________________________
The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with H
otmail.
http://www.windowslive.com/campaign/thenewbusy?tile=multicalendar&ocid=
PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5
________________________________________________________________________________
| Subject: | Re: schematic for a Challenger II |
| From: | "user9253" <fran4sew(at)banyanol.com> |
Doug,
The way to let others open a file is to save it on a file sharing website and then
provide a link to it on Matronics. I use WindowsLive. Even though it is
designed for photo sharing, you are allowed to share files with various extensions.
4AWG seems big for a small engine unless the battery is a long way from the
starter.
Placing diodes in parallel across the relays and contactors (with arrows pointing
towards positive) will protect the controlling switches from arcs and sparks.
Switching the grounded side of the master contactor instead of the hot side
will minimize the number of hot wires running to the instrument panel.
An avionics switch is not recommended because if it fails, everything connected
to it stops working. In your case, there are only two items. If each has
its own on-off switch, then an avionics switch is not needed.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294172#294172
________________________________________________________________________________
| From: | RGent1224(at)aol.com |
| Subject: | Re: RE: copper foil groundplane |
Check this out
_http://rst-engr.com/rst/catalog/airplane_antenna.html_
(http://rst-engr.com/rst/catalog/airplane_antenna.html)
Dick
In a message dated 4/14/2010 8:16:26 A.M. Central Daylight Time,
mdnanwelch7(at)hotmail.com writes:
Hi Bob,
Thanks for the detailed and informative response. Yes, I am very much a
DIY person.
I don't really have the $100 for the Miracle antenna (end-fed halfwave
dipole), so I guess I'll have to stick with a homemade one.
So far, I'm still leaning toward the belly mount dipole, and making a
spoke style grid of copper foil, where the steel rod mast mounts in the center
of the grid. I'll sure to get a good ground of the groundplane to the tube
frame.
Does more than four legs of a cu foil groundplane make it better? Or, is
that just a waste of copper tape?
I'm curious. After I get this antenna constructed, mounted and finished,
how does one check it's adjustment with a SWR meter. I mean, there aren't
many things you could do to the mast, except cut off a little. But, what
if you cut off too much?
Could you possibly explain the actual nuts and bolts of using an SWR
meter, and how it can allow a guy to improve his antenna's performance?
One more thing.... I am also building a GlaStar, and bought the factory
copper foil dipole antenna. I noticed it has triax cable, rather than
regular RG58. I assume this is because the extra layer of the triax acts as a
balun. I meant to check out how the triax connects at the junction of the
two copper strips, but forgot, and mounted it in the tail and closed it up.
For fiberglass airplanes that might use this type of "triax cable copper
foil dipole", how and where is the triax soldered, if it's soldered at all?
Thanks a lot!!
Mike Welch
The end-fed half-wave antenna has been around
for a long time and is a popular topic of
discussion and debate in the amateur radio
antenna forums. There's a particularly lucid
study of these beasties to be found at:
_http://www.aa5tb.com/efha.html
_ (http://www.aa5tb.com/efha.html) Of course, this article is dealing with
the lower
HF frequencies of interest to amateurs but the
physics scales nicely into the higher VHF range.
My sense is that while they can be "tuned" to
accommodate effects of installation, they're not
your grandpa's plug-n-play buggy whip. It's unlikely
that an end-fed half-wave stuck inside the fuselage
of a composite aircraft will be optimized out of the
box for that particular installation.
Having said that, we also know that antenna efficiency
in airplanes can be all over the map and still provide
satisfactory performance. I have no doubt that the
antenna offered has many "satisfied" users.
If the builder is not DIY shy, a few dollars in
materials can be crafted into an quarter-wave
over ground-plane antenna that will certainly
perform as well with more predictable results
for SWR. Getting to the center of a half-wave
dipole isn't hard if you put the center
half way up on the side of the fuselage and
wrap around the inside surface.
Distorting from a straight antenna will have
the effect of electrically lengthening the
antenna so trimming after installation with
some form of SWR instrument would be useful
. . . but probably wouldn't produce observable
differences in performance
I've just joined this group and have a couple of questions.
I have searched the archives, but finding my particular
answers is tough, to say the least. I'm getting very close to
installing the Icom A200 comm antenna in my tube & fabric
airplane (Kolb MkIII). I think I've chosen to go underneath
the fuselage, between the main gear legs, with the 23" steel
rod mast pointing down and rearward.
That will probably work as well as anything else.
You can ground the feedline shield to the steel-tube
structure.
Bob . . .
-List">http://www.matronics.com/Navigator?AeroElectric-List
ronics.com ww.matronics.com/contribution
____________________________________
The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with
Hotmail. _Get busy._
(http://www.windowslive.com/campaign/thenewbusy?tile=multicalendar&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5)
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | RE: copper foil groundplane |
Dick=2C
I'm very familiar with Bob Weir's stuff=2C and in fact=2C I built one of
these copper foil antennas a few years ago. I haven't installed it yet. I
f I can find it=2C I think I'm going to go ahead and use it.
I built the mast out of fiberglass=2C with the copper foil sandwiched ins
ide it. The mast is then soldered to a BNC connector=2C and faired in with
more fiberglass. Finally=2C I sanded everything nice and smooth=2C and pa
inted it grey.
Thanks for the reference=2C tho.
Mike Welch
From: RGent1224(at)aol.com
Date: Wed=2C 14 Apr 2010 10:19:48 -0400
Subject: Re: AeroElectric-List: RE: copper foil groundplane
Check this out
http://rst-engr.com/rst/catalog/airplane_antenna.html
Dick
In a message dated 4/14/2010 8:16:26 A.M. Central Daylight Time=2C mdnanwel
ch7(at)hotmail.com writes:
Hi Bob=2C
Thanks for the detailed and informative response. Yes=2C I am very much
a DIY person.
I don't really have the $100 for the Miracle antenna (end-fed halfwave dipo
le)=2C so I guess I'll have to stick with a homemade one.
So far=2C I'm still leaning toward the belly mount dipole=2C and making a
spoke style grid of copper foil=2C where the steel rod mast mounts in the
center of the grid. I'll sure to get a good ground of the groundplane to t
he tube frame.
Does more than four legs of a cu foil groundplane make it better? Or=2C
is that just a waste of copper tape?
I'm curious. After I get this antenna constructed=2C mounted and finishe
d=2C how does one check it's adjustment with a SWR meter. I mean=2C there
aren't many things you could do to the mast=2C except cut off a little. Bu
t=2C what if you cut off too much?
Could you possibly explain the actual nuts and bolts of using an SWR mete
r=2C and how it can allow a guy to improve his antenna's performance?
One more thing.... I am also building a GlaStar=2C and bought the factor
y copper foil dipole antenna. I noticed it has triax cable=2C rather than
regular RG58. I assume this is because the extra layer of the triax acts a
s a balun. I meant to check out how the triax connects at the junction of
the two copper strips=2C but forgot=2C and mounted it in the tail and close
d it up.
For fiberglass airplanes that might use this type of "triax cable copper
foil dipole"=2C how and where is the triax soldered=2C if it's soldered at
all?
Thanks a lot!!
Mike Welch
The end-fed half-wave antenna has been around
for a long time and is a popular topic of
discussion and debate in the amateur radio
antenna forums. There's a particularly lucid
study of these beasties to be found at:
http://www.aa5tb.com/efha.html
Of course=2C this article is dealing with the lower
HF frequencies of interest to amateurs but the
physics scales nicely into the higher VHF range.
My sense is that while they can be "tuned" to
accommodate effects of installation=2C they're not
your grandpa's plug-n-play buggy whip. It's unlikely
that an end-fed half-wave stuck inside the fuselage
of a composite aircraft will be optimized out of the
box for that particular installation.
Having said that=2C we also know that antenna efficiency
in airplanes can be all over the map and still provide
satisfactory performance. I have no doubt that the
antenna offered has many "satisfied" users.
If the builder is not DIY shy=2C a few dollars in
materials can be crafted into an quarter-wave
over ground-plane antenna that will certainly
perform as well with more predictable results
for SWR. Getting to the center of a half-wave
dipole isn't hard if you put the center
half way up on the side of the fuselage and
wrap around the inside surface.
Distorting from a straight antenna will have
the effect of electrically lengthening the
antenna so trimming after installation with
some form of SWR instrument would be useful
. . . but probably wouldn't produce observable
differences in performance
I've just joined this group and have a couple of questions.
I have searched the archives=2C but finding my particular
answers is tough=2C to say the least. I'm getting very close to
installing the Icom A200 comm antenna in my tube & fabric
airplane (Kolb MkIII). I think I've chosen to go underneath
the fuselage=2C between the main gear legs=2C with the 23" steel
rod mast pointing down and rearward.
That will probably work as well as anything else.
You can ground the feedline shield to the steel-tube
structure.
Bob . . .
-List">http://www.matronics.com/Navigator?AeroElectric-List
ronics.com
ww.matronics.com/contribution
The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with H
otmail. Get busy.
List href="http://www.matronics.com/Navigator?AeroElectric-List">http://w
ww.matronics.com/Navigator?AeroElectric-List
ms.matronics.com/">http://forums.matronics.com
tp://www.matronics.com/contribution">http://www.matronics.com/contribution
_________________________________________________________________
The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with H
otmail.
http://www.windowslive.com/campaign/thenewbusy?tile=multicalendar&ocid=
PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5
________________________________________________________________________________
| From: | Doug Ilg <doug.ilg(at)verizon.net> |
| Subject: | Re: schematic for a Challenger II |
Joe,
Oops. I guess attaching the file was a faux pas. Sorry.
Would you say that 6AWG is good enough for the fat wires, then?
Another oops. Ihave those diodesacross the coils on my diagram. Sent the wrong
one.
Good point on switching the ground side. Will do.
For the avionics switch, both of the switched units(EFIS and radio) require external
switches. Wish they didn't. I'll consider separating them if I can find
enough room on the relatively small panel. (The switches I'd like to use are rather
large.)
Doug Ilg
Grumman Tiger N74818, College ParkAirport (KCGS), Maryland
Challenger II LSS LW (N641LGreserved)- kit underway at Laurel Suburban (W18)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: RE: copper foil groundplane |
At 08:12 AM 4/14/2010, you wrote:
Hi Bob,
Thanks for the detailed and informative response. Yes, I am very
much a DIY person. I don't really have the $100 for the Miracle
antenna (end-fed halfwave dipole), so I guess I'll have to stick with
a homemade one.
I've had an antenna building article on my to-do list
for years. Unfortunately that list is long and the
antenna project is pretty far down. Suggest you start
with a manufactured "mount" like . . . .
http://tinyurl.com/y3a4lpf
This is an example of MANY similar products which
you can find at about any truck-stop on a major highway.
You can install the mating PL-259 coax connector
on your coax -OR- install a SO Male to BNC female
adapter to mate with your own installed BNC cable
male -OR- consider this pre-mfg assembly from
Radio Shack . . .
http://tinyurl.com/y7dzxpf
It has a PL-259 on one end that will mate with
your "truckers antenna mount". You can cut the
connector off the other end and install a cable
male to mate with your transceiver.
So far, I'm still leaning toward the belly mount dipole,
"dipole" or "vertical 1/4-wave"?
and making a spoke style grid of copper foil, where the steel rod
mast mounts in the center of the grid. I'll sure to get a good ground
of the groundplane to the tube frame. Does more than four legs of
a cu foil groundplane make it better? Or, is that just a waste of
copper tape?
Tests have shown that there's a diminishing return
on investment for adding radials to the ground plane.
To make a significant improvement one needs to double
the radials. The step from 4 is up to 8 . . . you can
see where that's taking us.
You'll need some sort of structural bracket
that grips a tube and supplies a suitable
flat against the inside surface of the fabric
for attaching the antenna. This bracket also be
suitable for grounding the coax shield to the
airframe. Getting robust connection to a ground
plane attached inside a fabric 'skin' is problematic.
The ship's existing metallic structure is a
reasonable substitute for the classic "spider
legs" ground plane.
I'm curious. After I get this antenna constructed, mounted and finished,
how does one check it's adjustment with a SWR meter. I mean, there
aren't many things you could do to the mast, except cut off a little.
Correct. If you were going to "go for the gold",
you'd make it extra long by about an inch and
then trim to length for best SWR at the selected
center frequency. The theroetical 1/4-wave centered
in the VHF comm band (129.5 Mhz) is 23.34 inches.
If you cut it to 22.34 inches the antenna is
calculated to center on 132.14 Mhz. So the
"tuning sensitivity" for this antenna is on the
order of 2.6 Mhz per inch of length. So trimming
say .1" at a time would let you "sneak up on it".
Alternatively, you can calculate a new length based
on measured center frequency using the 2.6"/MHz
sensitivity factor.
Now that we've fine tuned the theory, know also
that there are other factors that influence the
resonant frequency. An important one is a correction
for length/diameter ratio. I speak to this effect
in figure 13-6 of the 'Connection. If your antenna
rod is .125" diam stainless and is about 23" long,
then the l/d ratio is about 160. This translates
to an electrical "lengthening" of about 3.5% or
.81 inches. Gee, this translates to about 2 Mhz
shift in center frequency.
Further, bending your antenna aft for a rakish
appearance (or better ground clearance) has a
further lengthening effect. All this calculator
key-punching goes to demonstrate that the ideal
antenna is trimmed to length after installation
using some form of instrumentation.
Return on investment? The guy listening to your
transmitted signal wouldn't know the difference
between the "ideal" and "pretty close" antenna.
Further, DIRECTIONAL effects of airframe geometry
can have a PROFOUND effect on the very best of
antennas. This effect is discussed in the BALUN
construction article cited below.
Bottom line: 22" for a 1/4-wave stick is close
enough for government work. An SWR test at the
transceiver end of the feed line is most useful
as a gross check of antenna integrity. Check SWR
at say 1 Mhz steps from 118.0 to 135.0 and plot the
results. The "dip" in the plot shows the center
frequency of the antenna. The SWR shouldn't be
more than 3.0:1 over the full range of interest.
An antenna with a broken connection along the feed
line will have very high SWR numbers and probably
exhibit no clear "dip" in the plot.
But, what if you cut off too much?
That IS a problem only if you're pedantic about
getting the antenna performance centered on
129.5000000000 Mhz. If you "overshoot" a trimming
operation and the durn thing now centers at 131
Mhz, no big deal.
Could you possibly explain the actual nuts and bolts of using
an SWR meter, and how it can allow a guy to improve his antenna's
performance?
It's pretty simple. Use your ship's transmitter
as a signal source and plot measured SWR against
transmit frequency. When you're all done, the
SWR will be LOWEST at the design center. SWR
should not be more than 3:1 at the edges of
the band.
One more thing.... I am also building a GlaStar, and bought the
factory copper foil dipole antenna. I noticed it has triax cable,
rather than regular RG58. I assume this is because the extra layer
of the triax acts as a balun. I meant to check out how the triax
connects at the junction of the two copper strips, but forgot, and
mounted it in the tail and closed it up.
For fiberglass airplanes that might use this type of "triax cable
copper foil dipole", how and where is the triax soldered, if it's
soldered at all?
I've heard of this design but never had the opportunity
to run it through the lab. It's better than NO balun but
again, ROI is problematic. The outer shield could be
used two ways: Soldered to the inner shield 1/4-wave from
the antenna end only. This makes it a "bazooka" decoupling
sleeve.
http://tinyurl.com/y6xgese
Alternatively, it can solder to the inner shield 1/4-wave
away from the antenna as above. The other end of outer
shield solders to the center conductor at the antenna
end. This makes it a piece of transmission line. This
type of balun is easily synthesized without the use
of triaxial coax as shown here:
http://tinyurl.com/yytxwd3
I wouldn't discourage anyone from going for the best-
we-know-how-to-do in selection/fabrication, installation
and testing of antennas on the airplane. At the same
time, know that "missing the mark" by some small amount
is probably not a reason for ripping it out and starting
over.
Bob . . .
________________________________________________________________________________
| Subject: | Re: copper foil groundplane |
Check out Slim Jim and J-pole antennas on Google. They are end fed dipole
s.
John Greaves
VariEze N81JG
Redding, CA
-----Original Message-----
From: Mike Welch <mdnanwelch7(at)hotmail.com>
Sent: Tue, Apr 13, 2010 2:45 pm
Subject: RE: AeroElectric-List: copper foil groundplane
Doug,
No, I hadn't heard of this one. It sounds like this could be the perfec
t setup. Do you know how the wire is "oriented"? Can you just make a cir
cular loop, or ????
I do like the idea of this antenna, but since I'm between jobs right now
, funds are very scarce. Plus, I really wanted to make the antenna for my
plane, just for the experience.
Does anyone know of a DIY plan for this type of dipole end-fed com anten
na? What is in that little black box? (hopefully not some of that "specia
l smoke" that leaks out when you touch two wrong wires together!!)
If anyone knows of a way to make one these single wire dipole end-fed an
tennas, I'd sure appreciate a drawing or two.
Thanks again, Doug, for the tip!!
Mike Welch
Mike,
Have you looked at Miracle Antenna's Air Whip? http://www.miracleantenna.
com/AirWhip.htm It's a full dipole antenna that's made completely of flex
ible wire. It's also end-fed, so you don't need access to the middle of
the antenna for connection. You can put it anywhere in the fuselage that
's not shielded by conductive parts.
I'm not flying yet, but mine seems to work very well on the ground. It fi
ts quite well in the fiberglass nose cone of my Challenger. Based on a qu
ick look at a picture of a Kolb M3X, I'd guess you could do something simi
lar in your airplane. It might save you some of the hassle you're dealing
with.
FYI.
-Doug
Doug Ilg
Grumman Tiger N74818, College Park Airport (KCGS), Maryland
Challenger II LSS LW (N641LG reserved) - kit underway at Laurel Suburban
(W18)
From: Mike Welch <mdnanwelch7(at)hotmail.com>
Sent: Tue, April 13, 2010 1:15:25 PM
Subject: AeroElectric-List: copper foil groundplane
Hi guys,
I've just joined this group and have a couple of questions. I have sear
ched the archives, but finding my particular answers is tough, to say the
least.
I'm getting very close to installing the Icom A200 comm antenna in my tu
be & fabric airplane (Kolb MkIII). I think I've chosen to go underneath
the fuselage, between the main gear legs, with the 23" steel rod mast poi
nting down and rearward.
>
Hotmail is redefining busy with tools for the New Busy. Get more from your
inbox. See how.
========================
===========
========================
===========
========================
===========
========================
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________________________________________________________________________________
| Subject: | copper foil groundplane |
Found this. Just put in the freq and it tells you how long to make it.
Does that mean the length we're shooting for is the middle of the band?
http://www.m0ukd.com/Calculators/Slim_Jim/index.php
Glenn
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
n81jg(at)aol.com
Sent: Wednesday, April 14, 2010 1:50 PM
Subject: Re: AeroElectric-List: copper foil groundplane
Check out Slim Jim and J-pole antennas on Google. They are end fed
dipoles.
John Greaves
VariEze N81JG
Redding, CA
-----Original Message-----
From: Mike Welch <mdnanwelch7(at)hotmail.com>
Sent: Tue, Apr 13, 2010 2:45 pm
Subject: RE: AeroElectric-List: copper foil groundplane
Doug,
No, I hadn't heard of this one. It sounds like this could be the
perfect setup. Do you know how the wire is "oriented"? Can you just
make a circular loop, or ????
I do like the idea of this antenna, but since I'm between jobs right
now, funds are very scarce. Plus, I really wanted to make the antenna
for my plane, just for the experience.
Does anyone know of a DIY plan for this type of dipole end-fed com
antenna? What is in that little black box? (hopefully not some of that
"special smoke" that leaks out when you touch two wrong wires
together!!)
If anyone knows of a way to make one these single wire dipole end-fed
antennas, I'd sure appreciate a drawing or two.
Thanks again, Doug, for the tip!!
Mike Welch
Mike,
Have you looked at Miracle Antenna's Air Whip?
http://www.miracleantenna.com/AirWhip.htm It's a full dipole antenna
that's made completely of flexible wire. It's also end-fed, so you
don't need access to the middle of the antenna for connection. You can
put it anywhere in the fuselage that's not shielded by conductive parts.
I'm not flying yet, but mine seems to work very well on the ground. It
fits quite well in the fiberglass nose cone of my Challenger. Based on
a quick look at a picture of a Kolb M3X, I'd guess you could do
something similar in your airplane. It might save you some of the
hassle you're dealing with.
FYI.
-Doug
Doug Ilg
Grumman Tiger N74818, College Park Airport (KCGS), Maryland Challenger
II LSS LW (N641LG reserved) - kit underway at Laurel Suburban (W18)
From: Mike Welch <mdnanwelch7(at)hotmail.com>
Sent: Tue, April 13, 2010 1:15:25 PM
Subject: AeroElectric-List: copper foil groundplane
Hi guys,
I've just joined this group and have a couple of questions. I have
searched the archives, but finding my particular answers is tough, to
say the least.
I'm getting very close to installing the Icom A200 comm antenna in my
tube & fabric airplane (Kolb MkIII). I think I've chosen to go
underneath the fuselage, between the main gear legs, with the 23" steel
rod mast pointing down and rearward.
>
Hotmail is redefining busy with tools for the New Busy. Get more from
your inbox. See how.
===================================
===================================
===================================
===================================
________________________________________________________________________________
| Subject: | Re: copper foil groundplane |
| From: | "checkn6" <checkn6(at)yahoo.com> |
Inside the magic box
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294242#294242
Attachments:
http://forums.matronics.com//files/themiracleinside_131.jpg
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: "miracle antenna" |
At 04:32 PM 4/14/2010, you wrote:
>
>Inside the magic box
>
>Attachments:
>
>http://forums.matronics.com//files/themiracleinside_131.jpg
Hmmmm. . . . not especially impressive. I think I'll
write the folks an see if they'll send me an evaluation
sample.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Internal comm antennas for composites |
Check these data points . . .
http://davemorris.com/MorrisComLoop.cfm
http://www.aeroelectric.com/articles/Antennas/Popular_Antenna_Lore.pdf
http://www.aeroelectric.com/articles/ant_anal.pdf
http://www.aeroelectric.com/Pictures/Antenna/Figure_13-8.pdf
Bob . . .
________________________________________________________________________________
| Subject: | Re: schematic for a Challenger II |
| From: | "user9253" <fran4sew(at)banyanol.com> |
> I guess attaching the file was a faux pas.
There is nothing wrong with the way that you did it. I was only trying to explain
how to share a drawing with the extension of sch.
> Would you say that 6AWG is good enough for the fat wires, then?
I do not know. It all depends on the current draw of the starter and length of
wire. My Rotax 912 comes with 8awg for the starter. What have others used on
your type of plane and engine? You could try smaller wire and if the engine
cranks too slowly, then replace the wire with a larger size.
I assume that your plane will be used for low and slow fun flying. As long as
failure of the avionics switch does not disable critical equipment, then having
one switch for two devices is OK. Separate switches are ideal but one switch
will work.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294267#294267
________________________________________________________________________________
| From: | "Richard E. Tasker" <retasker(at)optonline.net> |
| Subject: | Re: schematic for a Challenger II |
Why is attaching a file a faux pas? Plenty of others do it. Yours was
quite small as attachments go... Attaching a 5MB file would be, in my
opinion, but an 84K file...
Dick Tasker
Doug Ilg wrote:
> --> AeroElectric-List message posted by: Doug Ilg
>
> Joe,
>
> Oops. I guess attaching the file was a faux pas. Sorry.
> Would you say that 6AWG is good enough for the fat wires, then?
>
> Another oops. I have those diodes across the coils on my diagram. Sent the
wrong one.
>
> Good point on switching the ground side. Will do.
>
> For the avionics switch, both of the switched units (EFIS and radio) require
external switches. Wish they didn't. I'll consider separating them if I can
find enough room on the relatively small panel. (The switches I'd like to use
are rather large.)
>
>
> Doug Ilg
> Grumman Tiger N74818, College Park Airport (KCGS), Maryland
> Challenger II LSS LW (N641LG reserved) - kit underway at Laurel Suburban (W18)
>
>
>
--
Please Note:
No trees were destroyed in the sending of this message. We do concede, however,
that a significant number of electrons may have been temporarily inconvenienced.
--
________________________________________________________________________________
| From: | "Jean Lowenhardt" <aeronca2(at)99main.com> |
| Subject: | noise suppression |
Installation instructions for a 12volt, 8amp wind driven generator
specify shielding on the output lead with no other noise suppression
requirements. Electrical system schematics for later models of the
aircraft, having engine driven generators, specify 0.01 microfarad
capacitors on the armature and stator leads. On the wind driven
generator, the regulator is housed within the generator unit and the
only external wires are the output and ground leads.
Should a capacitor be installed on the wind driven generator output lead
at the generator terminal for noise suppression in addition to the
original shielding requirement? If a capacitor is recommended, it must
be weather resistant. Therefore, please advise on part number and source
information if a capacitor is recommened.
Thanks for any input to my question and request.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | The Miracle Whip series antennas |
Robert Victor, President (VA2ERY)
Miracle Antenna
Montreal, Canada
Good morning sir,
By way of introduction, I'm an electronics engineer
retired from Hawker-Beechcraft after 46 years in the
electronics trades with an emphasis on aircraft. I
have a hobby business that supports the owner built
and maintained aircraft industry. My website is at
http://aeroelectric.com
I've been moderating electrical/electronics discussion
forums for amateur builders on Matronics for over 10
years. Our current membership is about 1800.
I also publish a document intended to assist my readers
in the crafting of failure-tolerant electrical systems;
https://matronics.com/aeroelectric/Catalog/pub/pub.html#P-Book
I was asked about VHF Com and VOR antennas suitable for
installation inside a composite aircraft. One reader
pointed out your offerings for a end-fed, half-wave
antenna specific to that task. I've reviewed this
and ancillary products on your website and in various
postings to the Internet.
Without a doubt, the end-fed, half-wave configuration
offers an opportunity but it also has some special
needs for impedance matching. Have you performed
antenna range testing on the VHF aircraft antennas?
Have you published any performance data for this
device over the frequency range of interest? Have
there been any studies of radiation patterns
associated with recommended installation methods?
I would like to be capable of advising my readers
from a position of knowledge and understanding about
your products. Anything you can offer to assuage my
ignorance would be appreciated. I'd like to add
this technology to the discussion on antennas when
the book is updated.
Finally, would you be willing to consign an exemplar
antenna to me for testing in local facilities? I'd
be pleased to return it to you along with any data
that is developed from the testing efforts.
Kindest regards,
Bob Nuckolls (K0DYH)
AeroElectric Connection
P.O. Box 130
Medicine Lodge, KS 67104-0130
Land line: (620) 886-3403
Mobile: (316) 209-7528
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: noise suppression |
At 09:31 AM 4/15/2010, you wrote:
>Installation instructions for a 12volt, 8amp wind driven generator
>specify shielding on the output lead with no other noise suppression
>requirements.
Shielding of such leads is a pointless effort. Any
noise produced by the generator will be CONDUCTED along
its power feed wire, not electro-statically coupled to
other potential victims.
>Electrical system schematics for later models of the aircraft,
>having engine driven generators, specify 0.01 microfarad capacitors
>on the armature and stator leads. On the wind driven generator, the
>regulator is housed within the generator unit and the only external
>wires are the output and ground leads.
>Should a capacitor be installed on the wind driven generator output
>lead at the generator terminal for noise suppression in addition to
>the original shielding requirement? If a capacitor is recommended,
>it must be weather resistant. Therefore, please advise on part
>number and source information if a capacitor is recommened.
>Thanks for any input to my question and request.
Try it and see. The responsible supplier will
conduct noise tests in a lab and supply
necessary noise suppression technology as
part of the product. If the as-delivered
generator didn't come with filters (and they're
not called out on installation instructions) then
an assumption follows that no filtering is
needed.
Some rudimentary flight-testing after installation
will go to proving/disproving that assumption.
Come back to this discussion with your findings
if indeed the critter turns out to be noisy.
Bob . . .
________________________________________________________________________________
| From: | "Jean Lowenhardt" <aeronca2(at)99main.com> |
| Subject: | Noise suppression |
Installation instructions for a 12volt, 8amp wind driven generator
specify shielding on the output lead with no other noise suppression
requirements. Electrical system schematics for later models of the
aircraft, having engine driven generators, specify 0.01microfarad
capacitors on the armature and stator leads. On the wind driven
generator, the regulator is housed within the generator unit and the
only external wires are the output and ground leads.
Should a capacitor be installed on the wind driven generator output lead
at the generator terminal for noise suppression in addition to the
original shielding requirement?
If a capacitor is recommened, it must be weather resistant. Therfore,
please advise on part number and source information if a capacitor is
recommened.
Thanks for any input to my question and request.
Hugh Loewenhardt
aeronca2(at)99main.com
restoring Fairchild 24C8C, N15076
Stonington, Ct
________________________________________________________________________________
| Subject: | 1/2 Wave Ring Antenna |
| From: | "user9253" <fran4sew(at)banyanol.com> |
Has anyone ever experimented with a 1/2 Wave Ring Antenna? It is described here: http://www.slvrc.org/902band/902antennas.htm
It could be mounted on a metal turtle deck and covered with non-conductive fabric
or fiberglass for streamlining. Its low profile would have less drag than
a quarter wave antenna at high speeds.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294317#294317
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: The Miracle Whip series antennas |
At 10:41 AM 4/15/2010, you wrote:
>
>
>Robert Victor, President (VA2ERY)
>Miracle Antenna
>Montreal, Canada
>
>I would like to be capable of advising my readers
>from a position of knowledge and understanding about
>your products. Anything you can offer to assuage my
>ignorance would be appreciated. I'd like to add
>this technology to the discussion on antennas when
>the book is updated.
I received a pleasant phone call from Mr. Victor.
He was unwilling to share any test data . . . backed
by the notion that such sharing left his venture
open to competition by folks who might exploit
his IR&D efforts.
This is a real risk for simple, easily fabricated
products. He did offer the idea that the Miracle
Whip was not an end-fed but center-fed half-wave
dipole. He explained that the dipole is formed by
exposing 1/4-wave of center conductor of the far end of
the feed line. One then moves 1/4-wave toward the
transmitter and inserts a high efficiency, common-
mode choke. That's what the 7-turns of coax through
the torroid core is all about.
This inserts a discontinuity in the shield. The
effect is that the INSIDE of the coax is a feed-line
out to the center and the outside of the coax shield
beyond the choke becomes one-half of the dipole.
This means that the "wire" we see wrapped through
the core in . . .
>http://forums.matronics.com//files/themiracleinside_131.jpg
is actually an unbroken length of coaxial cable. The
magic comes from core selection for high permeability
while offering the lowest possible losses at VHF
frequencies. No doubt a high quality ferrite material.
When I get the RF bench running fully and have the
time, I'll fiddle with the concept a bit and see what
I can confirm with the test equipment.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: 1/2 Wave Ring Antenna |
At 11:02 AM 4/15/2010, you wrote:
>
>Has anyone ever experimented with a 1/2 Wave Ring Antenna? It is
>described here:
>http://www.slvrc.org/902band/902antennas.htm
>It could be mounted on a metal turtle deck and covered with
>non-conductive fabric or fiberglass for streamlining. Its low
>profile would have less drag than a quarter wave antenna at high speeds.
I'm planning on building a cousin to this antenna for
my 2M storm watch transceiver. See:
http://www.antennex.com/preview/2mddrr.htm
This is the 1/4 wave version. Given that both the
1/4 and 1/2 wave antennas are vertically polarized
says that all the magic happens in that short vertical
mast that goes to ground. This becomes the same thing
as a short vertical with a strong top-hat loading
scheme. So whether the "top hat" is 1/4 or 1/2 wave
in circumference probably offers little difference in
performance.
Given the lengthening effect of so severe a
"rake angle" on this antenna, the physical length
of a 1/4-wave will be shorter than the classic
22" whip. 22" bent around in a circle would give
us less than 6" diameter and about 2" tall for VHF
Comm frequencies. This cross section, even if well
faired, could offer much more drag than the simple
whip stuck out in the breeze.
However, this form of antenna might perform well
inside a composite fuselage.
The biggest problem with heavily loaded antennas
is loss of band-width. They tend to be sharply
tuned at the design frequency with efficiency
falling off rapidly either side. The extreme example
of this phenomenon is demonstrated by small diameter
loop antennas for lower ham frequencies. They
have to be fitted with motor driven capacitors to
allow remote tuning to the frequency of interest.
Circulating currents tend to be very high, voltage
across the tuning capacitor is quite high. To keep
the losses low at such high currents, the antenna
is made from 3" DWV copper!
The DDRR antenna needs a high conductivity ground
plane that's at least 2x the antenna diameter. So
a 6" DDRR might be built on a 12" square piece of
copper clad that could become a "shelf" of sorts
in the tailcone. Further, that same sheet might
also be a good mounting location for the transponder
antenna. Food for thought.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Battery maintenance philosophies to meet design goals |
>If I'm going to ask an opinion of someone on the list, then I
>certainly must provide accurate information - or expect no answer.
>I'm using Odessey and happy with it so far. I have no intention of
>changing at this time. But, I was interested in the answer to the
>proposed question. I am always interested in a less expensive, but
>adequate replacements for equipment.
>Perhaps changing a battery each year is a waste of money. And I've
>been called an old FUDdy before, but it is certainly not out of
>fear, uncertainty, or doubt.
>I change a battery a year because:
>
>1. It is recommended by an expert in the field - Electric Bob
I did NOT recommend it. I suggested it as
an option to be considered and adopted pending
YOUR assessment of design goals, ways in which
you choose to spend your $time$ and tools you
plan to acquire to execute a considered preventative
battery maintenance program.
>2. My ignorance dictates that I listen to the experts
I'd rather you use my offerings more as teacher
than as expert. If you don't understand the
fundamentals upon which best decisions are made,
then you are at risk for falling victim to anyone
who wraps themselves in the mantle of "expert"
>3. It establishes a reasonable means to avoid failure
Let us assume you're going to buy a Hawker-Enersys
super battery of some kind and you plan to run
it until no longer suitable for flight? What
criteria and tools to YOU plan to use to monitor
that condition? Whether you swap every year
or run it until no longer suited for flight,
the means by which you avoid 'failure' lies
entirely in your lap, not the suggestions
of anyone else on the list.
>4. It is not overly expensive
If it's not the LEAST expensive, then
don't do it.
>5. The batteries are used in other equipment and not wasted.
Can you quantify "wasted"? Let's say you install
a shiny new 18 a.h. battery and your endurance
analysis shows that you need 12 a.h. at a 3 hour
rate to meet your battery only endurance goals.
When it's time to replace that battery, it will
still be cranking the engine just fine. When you
swap out an el-chesso battery at one year, it
too will still be cranking the engine just fine.
Both scenarios will remove a battery from your
AIRPLANE that may still have some degree of
usefulness NOT in an airplane. Which scenario
offers the most/least "waste"?
>6. The oldest battery at any moment in my RV is 2 years.
So is the main battery (which I presume was new
last year) going to replace the 2-year old
aux battery soon?
>7. I don't have to bother with capacity checks
I prefer to express it differently. You battery
preventative maintenance program is optimized
to expend the minimum $time$ to insure compliance
with your design goals.
>I also change my tires before they fail. Anyone who wants the old
>ones just let me know.
Boy . . . do I remember those days! There was a
Texaco station owner who took pity on me and
gave me a call when he had extra-ordinarily
meaty take-off tires I could buy.
>I change my hoses before they fail. Anybody want the old ones?
Naw . . . ran too many of those until they blew . . .
>I don't like being stranded in remote locations because I tried to
>stretch the life of consumables such as batteries.
In this case, the "stretching" thing doesn't have
much tension in it. Unless you're installing big lead
pigs with the idea that your battery-only endurance
requirements can be met with only 25% of as-new capacity,
then maybe you would stretch it.
Now, Z13/8 does offer an opportunity to take battery
capacity completely out of the FMEA study for
endurance. Cranking the engine is a pretty good test
of a battery to be MINIMALLY functional where a second,
engine driven power source replaces the battery as
the stand-by power source.
>Just call me an old fuddy.
Old fuddies are those among us who allow our airplanes
to get WAAaaayyyy ahead of us. For many of our brethren
in the TC aircraft world, the airplane is probably too
far "out in front" . . . and they don't have to be grey-
haired to suffer this condition! This assertion is supported
by the many dark-n-stormy-night stories we've read and analyzed
on the List over the years.
I'll respectfully suggest that if folks are participating
here just to ask for and run with an answer that appears
delivered with some expertise, you may be better off
sticking with a C-172 style electrical system. The value
to be gathered here is not the advise of experts or
a mass of anecdotal experience. It's my fondest wish that
folks flying systems crafted from ideas offered here
UNDERSTAND what's going on and are in command and control
of their electro-whizzy destiny.
>Ira, thanks for researching the correct info on the battery and
>providing your opinion. I appreciate it.
>It appears from your comment that you prefer Panasonic
>batteries. Which model do you use? Why do you believe that battery
>is better than an Odessey?
Panasonic makes no product on a par with Hawker-
Enersys. My studies of aircraft battery products
have convinced me and my colleagues that H-E
products are the cream of the battery crop. In no
way should that statement be interpreted to mean
that Panasonic products do not offer good value.
Only the builder/operator of an OBAM aircraft
can make the determination of value based on their
own cost-of-ownership studies.
> Does it have more AH capacity? Does it have faston tabs or screw
> on terminals?
There's a collection of battery manufacturer's
data including Panasonic and H-E on my website
at:
http://aeroelectric.com/Mfgr_Data.html
>Your suggestion of replacing a battery every two years seems like a
>reasonable thing to do - especially if one charges the batteries to
>capacity periodically.
How do we quantify "reasonable" . . . how many
watt seconds of energy are expected to be contained
in an 18 ah battery after 2 years of "reasonable"
use and maintenance?
Please don't think I'm picking on you my friend.
I think it's important that words be crafted to
illustrate well considered recipes for success.
It's important that meaning/understanding is not
sacrificed to misinterpretation.
Bob . . .
________________________________________________________________________________
| From: | "Fisher Paul A." <FisherPaulA(at)johndeere.com> |
| Subject: | 1/2 Wave Ring Antenna |
There has been some discussion about a ring antenna here: http://www.vansairforce.com/community/showthread.php?t=52676
The discussion was specifically about APRS which uses 144.39MHz in the ham bands,
but it's close enough to aviation frequencies that it might give you some ideas.
The biggest issue on this thread is where do you mount such an antenna
in an all metal airframe. Obviously, the problem becomes much simpler if you
eliminate that!
Paul A. Fisher
Q-200, N17PF - copper foil dipole embedded in the vertical tail
RV-7A, N18PF - 1/4 wave sticking out in the wind!
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of user9253
Sent: Thursday, April 15, 2010 11:02
Subject: AeroElectric-List: 1/2 Wave Ring Antenna
Has anyone ever experimented with a 1/2 Wave Ring Antenna? It is described here: http://www.slvrc.org/902band/902antennas.htm
It could be mounted on a metal turtle deck and covered with non-conductive fabric
or fiberglass for streamlining. Its low profile would have less drag than
a quarter wave antenna at high speeds.
Joe
--------
Joe Gores
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Accurate Altitude and Airspeed |
4/15/2010
Hello Mike, You wrote: "Not sure why this (altitude variation with airspeed)
would be, or more importantly, how to fix it."
Hello Bernie, You wrote: "There didn't seem to be any theory behind it."
This is not a very rare or mysterious phenomena. Inaccurate airspeed
indications can be caused by inaccurate dynamic and static air pressure
forces. Inaccurate altitude indications can be caused by inaccurate static
pressure forces.
AIRSPEED. Let's talk about inaccurate airspeed measurements first. An
airspeed indicator is a balancing mechanism. It balances the difference
between a force created by dynamic air pressure and a force created by
static air pressure. The force from the dynamic air pressure is the result
of the forward movement of the airplane. The faster the airplane moves the
greater the force exerted.
In order to get an accurate measure of that dynamic force one needs to
accurately sense the free stream dynamic air pressure and send it to the
airspeed indicator via leak and kink free tubing. That means sensing the air
movement in the actual direction that the airplane is moving and having that
air movement not affected by some local air flow direction change caused by
the airframe itself. This is why you sometimes see flight test airplanes
with a long boom sticking out forward with a small vane mechanism on the
front of it. This boom and vane mechanism, along with connecting tubing, is
a pitot tube system intended to accurately measure the force from the free
stream dynamic air pressure without any inaccuracies introduced by local
airframe air flow. See Note One below.
So much for the dynamic force side of the airspeed indicator balancing act,
what about the static force side? An accurate static force is provided by a
static port ideally located somewhere on the airframe such that it is
measuring the true static air pressure. But finding that ideal location and
making the perfect static port that does not introduce static air pressure
errors is not always so quick and easy. And what do we do if we discover
that the static port that we have installed is not producing accurate static
air pressure? See Note Two below.
ALTITUDE. An altimeter is also a balancing mechanism. It measures the
difference between the initial altitude setting of the altimeter mechanism
as compared to the static air pressure encountered by that same mechanism
while in flight and displays that difference in some lineal measurement
(usually in feet in our part of the world). If the static pressure provided
to the altimeter via the static port and the connecting tubing is in error
or changes with the airplane's airspeed, when the actual altitude is
constant, then the altimeter's altitude indication will be in error. And
what do we do if we discover that the static port that we have installed is
not producing accurate static air pressure? See Note Two below.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
Note One: Why don't we use these long boom and vane type pitot tubes on our
experimental amateur built aircraft? Because the boom and vane would take a
terrific beating from people walking into them on the ground and because the
dynamic force errors introduced by the type of pitot tubes that we commonly
use are just not great enough to cause us concern. There is not very much we
can do about adjusting the force coming from dynamic air pressure other than
using a pitot tube located a sufficient distance from a disturbing piece of
airframe (usually the bottom surface of a wing) and avoiding a leak or kink
in the tubing going from the pitot tube to the airspeed indicator.
Note Two: So we have built our airplane, installed our static port(s), and
discovered that we are getting inaccurate airspeed and / or altitude
indications and decide to do something about it. We could just go on
installing new static ports in different locations, but that is a lot of
work and we are not assured of better results. So we should do just what the
big boy aerodynamic types do, we fudge or bandaid as needed to get the air
to give us the results that we want.
Let's say that the airspeed indicator is reading too high -- it says the
airplane is going faster than it really is. (See Note Three). The dynamic
air pressure side of the airspeed indicator is providing too much force in
the desired balancing act. How can we counteract that excess dynamic force?
We increase the static force being fed to the airspeed instrument by the
static port by installing a small wedge just aft of the opening on the
static port (thin edge of the wedge facing forward towards the hole). This
small wedge causes air to pile up and increase the static air pressure going
to the airspeed indicator (and also to the altimeter unless you have
provided separate static ports for the two instruments) and give us the
accurate force balance measurement that we want.
Let's say that the altimeter reading goes down 200 feet when you speed up 60
miles per hour (Mike, you did not say which direction your altitude was
changing with the changes in airspeed). This means that the static port is
feeding greater than static pressure as your airplane flies faster. How can
we reduce that undesired increase in static air pressure? We install a small
wedge in front of the hole in the static port (thin edge of the wedge facing
aft towards the hole) to shield it a bit from dynamic air pressure coming
from the front in order to get a more stable and accurate altitude reading.
How do we get the right size wedge facing the correct direction to get the
airspeed and altitude results that we want? The same way the big boys do:
TRIAL AND ERROR and MORE TRIAL AND ERROR. Because our airplanes are
experimental, amateur built we are permitted to do just that -- experiment.
Note Three: So now we know how to tweak our static port(s) to give us
accurate airspeed and altitude information, but how do we know that the
airspeed and altitude information is inaccurate in the first place and
during our trial and error efforts how do we know when we have achieved the
accuracy that we are seeking? The answer to those two questions is not as
simple as one might first expect. I won't attempt to answer them here
because the answers are too big and complex to answer in this forum. What I
will suggest is that the reader google "accurate airspeed" and "accurate
altitude" and delve into those subjects to the level desired. Here is just
one source you will find:
http://gpsinformation.net/main/altitude.htm
Note Four: This is a personal view point. There are several methods
available for determining accurate true airspeed. Some rather elaborate --
some use GPS. Just google "accurate airspeed using GPS".
One thing that I've never quite understood regarding these methods is the
focus on precisely determining airspeed accuracy indication in the cruising
airspeed range. If I determine that my airspeed indicator shows 150 knots
indicated airspeed and I determine through some elaborate scheme that I am
actually only going 145 knots through the air what do I do with that
information? Being 5 nautical miles short of my destination after a one hour
flight is a trivial naviagation error contribution compared to all the other
error sources (such as heading, wind, and climb airspeed) that I have to
contend with and should overcome anyway by some means of real time enroute
navigation.
I think that if I were going to invest a lot of time and effort in
determining my exact airspeed error I would be inclined to do that
determination in the approach airspeed arena, not the cruising airspeed
arena. And even then I would not be obsessed with absolute airspeed
accuracy, I'd just want to know what number on the indicator gives me the
right kind of safe approach and landing time after time.
================================================
----- Original Message -----
From: <bwilder(at)tqci.net>
Cc: "mike mccann" ; "Pulsar builders"
Sent: Thursday, April 15, 2010 9:18 AM
Subject: Re: Here's an odd question
>I noticed that the back half of the round washer where the static exits on
> the SR22 had the back half of it filed down so there was in effect a
> little shield protecting the static exit hole. ((Sorry about this
> description.)
>
> I asked the people at their booth why they did that. I think I attended
> four air shows before I found someone who was involved with the
> engineering of the system. The answer - - - - "That is what we had to do
> to make the system work right". There didn't seem to be any theory behind
> it. They indicated that they had to fiddle around to get it to behave the
> way they wanted. Maybe they were just trying to get rid of me.
>
> In any event, I did the same with mine and it works fine.
>
> Bernie Wilder
=============================================
>>
>> ----- Original Message -----
>> From: mike mccann
>> To: Pulsar builders
>> Sent: Thursday, April 15, 2010 5:06 AM
>> Subject: Here's an odd question
>>
>>
>> All,
>>
>> Utilizing a GPS, I've found that my altimeter in my Pulsar varies with
>> changes in airspeed (altitude will change 100-200 feet with speed
>> changes of 60 mph).
>>
>> Has anyone ever heard of this. Not sure why this would be, or more
>> importantly, how to fix it.
>>
>> Many thanks,
>>
>> Mike
>>
>> Pulsar 1
>> N116Km
________________________________________________________________________________
| From: | Tim Shankland <tshankland(at)sbcglobal.net> |
| Subject: | Re: 1/2 Wave Ring Antenna |
Boy that brings back memories I had a two meter halo antenna on the back
of my car in the the 1960's, the principle advantage was that it was
horizontally polarized like most of the other hams base station's. By
the way a much younger version of myself is the middle one of the group.
Tim Shankland 601HD flying ( no halo antenna)
Robert L. Nuckolls, III wrote:
>
>
> At 11:02 AM 4/15/2010, you wrote:
>
>>
>>
>> Has anyone ever experimented with a 1/2 Wave Ring Antenna? It is
>> described here:
>
>
>> http://www.slvrc.org/902band/902antennas.htm
>
>
>> It could be mounted on a metal turtle deck and covered with
>> non-conductive fabric or fiberglass for streamlining. Its low
>> profile would have less drag than a quarter wave antenna at high speeds.
>
>
> I'm planning on building a cousin to this antenna for
> my 2M storm watch transceiver. See:
>
> http://www.antennex.com/preview/2mddrr.htm
>
> This is the 1/4 wave version. Given that both the
> 1/4 and 1/2 wave antennas are vertically polarized
> says that all the magic happens in that short vertical
> mast that goes to ground. This becomes the same thing
> as a short vertical with a strong top-hat loading
> scheme. So whether the "top hat" is 1/4 or 1/2 wave
> in circumference probably offers little difference in
> performance.
>
> Given the lengthening effect of so severe a
> "rake angle" on this antenna, the physical length
> of a 1/4-wave will be shorter than the classic
> 22" whip. 22" bent around in a circle would give
> us less than 6" diameter and about 2" tall for VHF
> Comm frequencies. This cross section, even if well
> faired, could offer much more drag than the simple
> whip stuck out in the breeze.
>
> However, this form of antenna might perform well
> inside a composite fuselage.
>
> The biggest problem with heavily loaded antennas
> is loss of band-width. They tend to be sharply
> tuned at the design frequency with efficiency
> falling off rapidly either side. The extreme example
> of this phenomenon is demonstrated by small diameter
> loop antennas for lower ham frequencies. They
> have to be fitted with motor driven capacitors to
> allow remote tuning to the frequency of interest.
> Circulating currents tend to be very high, voltage
> across the tuning capacitor is quite high. To keep
> the losses low at such high currents, the antenna
> is made from 3" DWV copper!
>
> The DDRR antenna needs a high conductivity ground
> plane that's at least 2x the antenna diameter. So
> a 6" DDRR might be built on a 12" square piece of
> copper clad that could become a "shelf" of sorts
> in the tailcone. Further, that same sheet might
> also be a good mounting location for the transponder
> antenna. Food for thought.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Valin & Allyson Thorn" <thorn(at)starflight.aero> |
Hi Longg,
Yes, our Legacy's weight and c.g. location are one of my focus areas of
concern. Houston is just too hot and humid to not have an A/C in an
airplane like the Legacy with a bubble canopy. I figure half our flights
will be local, low altitude with no relief from the temps with altitude. To
make up for the 40 lb A/C unit behind the seats, I've saved 17 lbs with an
MT propeller vs. the Hartzell. Of course, that weight behind the seats
hurts the aft c.g. tendency of the basic design. So the batteries (30 lbs)
are going on the firewall. Also, we plan on a G900X integrated avionics
system which is going to hurt weight but help move the c.g. forward. Also,
the A/C unit is easily removable for winter months or when the payload
capability is needed.
On the electrical configuration, I subscribe to the design goal that the
failure of an alternator in flight should not prevent comfortably continuing
on to your destination - at least VFR. I do have a Dynon PFD planned as a
backup. With the SD-20, though, I can cover the G900X system with Wx Link
and Traffic Awareness systems off.
Valin
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
longg(at)pjm.com
Sent: Tuesday, April 13, 2010 11:19 AM
Subject: RE: AeroElectric-List: Re: Z-12 Twist?
Wow,
The Legacy is already CG sensitive with the big motor, then you install
the air-conditioning stuff which moves the CG aft and you've stopped the
big guys from sweating so they're no longer losing weight which makes
the plane more sensitive to gross weight when you fill up the 32.5 gal
fuel tanks. Now, you either need more power or you need to buy a 40 amp
alternator to save 4 pounds so you can carry a change of clothes for the
weekend. To save more weight I'd install the SD-8 and when #1 goes
south, shut down the air-conditioning, turn out all the lights and run
home on a 1 amp Dynon. When the 100 amp job goes you'll be sweating
bullets anyway so the air-conditioning will simply become camping gear
at that point.
That said, I really do enjoy the Legacy.
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | is a balun necessary |
Guys=2C
I'm building a 1/4 wave com antenna and have most of it completed=2C exce
pt for adding a balun.
Can someone answer this question for me=3B do I need a balun=2C or more p
recisely=2C what is it about an antenna that tells you you should install o
ne?
If I need one=2C the time to add it is now!! Easy now=2C not so easy lat
er!
My antenna has (4) 1/2" wide copper foil strips=2C soldered to form an "X
" (plus enough copper strips soldered to form a 2" x 2" sq. plate). Mounte
d in the center of the X is a 1/8" steel mast (welding rod). The coax shie
ld solders directly to the groundplane=2C and the coax's center conductor i
s fastened under a little screw that secures the mast.
Upon initial construction=2C the lengths of all the components are extra
long. The copper radials are 24" at the moment. The mast will start off a
t 23". Does an anyone have an opinion as to the lengths I should trim thes
e parts down to?
I DO have an SWR meter that I will be using to check for standing waves.
One more quick question regarding the antenna's components lengths. Wher
e is it that the length supposedly begins? If you have a 2" x 2" square co
pper plate=2C and each of the 4 copper tape radials are soldered to the pla
te=2C where is the radials length considered to begin? Is it from the very
center of the 2" x 2" plate=2C or is it from the point where the tape leav
es the edge of the plate...and actually begins being just copper foil arm?
Same for the mast. If I take a 1/8th" solid steel rod=2C and form a loop
on one end (to be able to mount it to a small plexiglass block)=2C where i
s the zero point on the rod? Is it the point where the coax fastens to the
mounting bolt=2C the end of the coax where it parts from the sheilding=2C
etc?
I know for a com radio we're shooting for 22"-23" roughly=2C for the ante
nna's lengths. I'm just a little lost on where those lengths actually begi
n. Plus=2C what if the radials are a little extra long? Does that hurt re
ception?
Thanks for your help=2C
Mike Welch
_________________________________________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with Hot
mail.
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ID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4
________________________________________________________________________________
| Subject: | Re: is a balun necessary |
| From: | Bill Boyd <sportav8r(at)gmail.com> |
I'll take a stab at it. Conventional wisdom is to make the radials 3-5%
longer than the radiating element (mast). For optimum impedance matching of
antenna to coax, the angle between the mast and radials should be about 120
degrees. A 90 degree angle is going to produce a lower impedance, closer to
36 ohms, and a resulting higher VSWR at resonance. In other words, no
matter how precisely you trim everything, hunting for lowest SWR, it won't
reach 1:1 unless the antenna impedance at resonance is 52 ohms, just like
the coax. I don't know the exact math on this, but I'll eyeball a guess
that 1.3:1 - 1.5:1 is the best you'll see with radials at right angles to
the mast. NOT likely to matter in practice, except that the air band spans
a wide % frequency range, and an antenna broadband enough to cover 118-136
MHz needs to have as low as possible a resonant (center-frequency) SWR in
order not to have a high SWR at the band edges. You want less than 2:5:1 at
the limits to keep the transmitter happy and prevent power output fold-back
from the radio's protective circuits. On receive, you'll never hear the
difference.
A balun will make no practical difference in the operation of a quarter-wave
vertical whip antenna such as you are building. I twill add weight, cost,
complexity and exact a small" efficiency surcharge." I'd strongly recommend
leaving it out.
Make your measurements from the point where the conductors leave the coax
shield. The radius of the copper plate counts as part of the radial length.
Any center conductor beyond the coax braid counts as part of the mast
length. In practice, the dimensions matter little except as a starting
point for trimming with the SWR meter.
Enjoy the exercise.
Bill Boyd
On Fri, Apr 16, 2010 at 9:16 AM, Mike Welch wrote:
> Guys,
>
> I'm building a 1/4 wave com antenna and have most of it completed, except
> for adding a balun.
> Can someone answer this question for me; do I need a balun, or more
> precisely, what is it about an antenna that tells you you should install
> one?
> If I need one, the time to add it is now!! Easy now, not so easy later!
>
>
> My antenna has (4) 1/2" wide copper foil strips, soldered to form an "X"
> (plus enough copper strips soldered to form a 2" x 2" sq. plate). Mounted
> in the center of the X is a 1/8" steel mast (welding rod). The coax shield
> solders directly to the groundplane, and the coax's center conductor is
> fastened under a little screw that secures the mast.
>
> Upon initial construction, the lengths of all the components are extra
> long. The copper radials are 24" at the moment. The mast will start off at
> 23". Does an anyone have an opinion as to the lengths I should trim these
> parts down to?
> I DO have an SWR meter that I will be using to check for standing waves.
>
> One more quick question regarding the antenna's components lengths.
> Where is it that the length supposedly begins? If you have a 2" x 2" square
> copper plate, and each of the 4 copper tape radials are soldered to the
> plate, where is the radials length considered to begin? Is it from the very
> center of the 2" x 2" plate, or is it from the point where the tape leaves
> the edge of the plate...and actually begins being just copper foil arm?
>
> Same for the mast. If I take a 1/8th" solid steel rod, and form a loop
> on one end (to be able to mount it to a small plexiglass block), where is
> the zero point on the rod? Is it the point where the coax fastens to the
> mounting bolt, the end of the coax where it parts from the sheilding, etc?
>
> I know for a com radio we're shooting for 22"-23" roughly, for the
> antenna's lengths. I'm just a little lost on where those lengths actually
> begin. Plus, what if the radials are a little extra long? Does that hurt
> reception?
>
> Thanks for your help,
>
> Mike Welch
>
> ------------------------------
> The New Busy is not the too busy. Combine all your e-mail accounts with
> Hotmail. Get busy.<http://www.windowslive.com/campaign/thenewbusy?tile=multiaccount&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4>
>
> *
>
> *
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: is a balun necessary |
At 08:16 AM 4/16/2010, you wrote:
Guys,
I'm building a 1/4 wave com antenna and have most of it completed,
except for adding a balun.
Can someone answer this question for me; do I need a balun, or more
precisely, what is it about an antenna that tells you you should install one?
The chapter on antennas and feedlines in the 'Connection
explains this. A 1/4-wave, bottom feed whip antenna
is an UNbalanced antenna and does not need a balun
to accept connection to a coaxial feed line.
My antenna has (4) 1/2" wide copper foil strips, soldered to form an
"X" (plus enough copper strips soldered to form a 2" x 2" sq.
plate). Mounted in the center of the X is a 1/8" steel mast (welding
rod). The coax shield solders directly to the groundplane, and the
coax's center conductor is fastened under a little screw that secures the mast.
How did you insulate the mast from the ground plate?
How is the mast attached to the rest of the assembly?
Upon initial construction, the lengths of all the components are
extra long. The copper radials are 24" at the moment. The mast will
start off at 23". Does an anyone have an opinion as to the lengths I
should trim these parts down to?
I DO have an SWR meter that I will be using to check for standing waves.
Suggest you cut the radials and antenna to 22". Use
the SWR meter at the transceiver to assure that SWR
is 3:1 or less over 118 to 135 mHz.
One more quick question regarding the antenna's components
lengths. Where is it that the length supposedly begins? If you have
a 2" x 2" square copper plate, and each of the 4 copper tape radials
are soldered to the plate, where is the radials length considered to
begin? Is it from the very center of the 2" x 2" plate, or is it
from the point where the tape leaves the edge of the plate...and
actually begins being just copper foil arm?
At the center.
Same for the mast. If I take a 1/8th" solid steel rod, and form a
loop on one end (to be able to mount it to a small plexiglass block),
Hmmmm . . . What kind of airplane are we talking about here?
Plexiglas is not particularly "structural" and a single
fastener through a loop on the end of the antenna
rod is not terribly resistant to rotation and loosening.
Antennas tend to be ignored until AFTER the radio quits
working. The design you describe is not particularly robust.
Have you considered using a CB antenna adapter like I linked in a
posting earlier this week?
http://tinyurl.com/y3a4lpf
You can drill a hole in a 3/8-24 bolt to accept your antenna rod
and silver-solder the rod to the bolt. The "booger" the treads of
the bolt and lube it with grease before you screw it into
the top fitting of the adapter. This makes a nice, gas-tight
electrical and robust mechanical fit between the adapter and
the antenna rod.
The other end is fitted with a common coax connector which
is easy to adapt to your feedline.
. . . where is the zero point on the rod? Is it the point where the
coax fastens to the mounting bolt,
Yes.
or the end of the coax where it parts from the sheilding, etc?
Exposed center conductor ADDS to overall length
and should be minimized. But this is pretty easy
to keep at or below 1" and is not significant in
terms of antenna performance.
I know for a com radio we're shooting for 22"-23" roughly, for the
antenna's lengths. I'm just a little lost on where those lengths
actually begin. Plus, what if the radials are a little extra
long? Does that hurt reception?
No, the radials are not critical. If you were cutting
your copper foil strips from a large sheet, I would have
made them wider for robustness . . . 1-2" would have
been nice. But if you're working with 1/2" wide tape,
then what you have is what you have and will work fine.
Make periodic inspections of the joints where the
tape comes onto the grounding plate.
Bob . . .
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | is a balun necessary |
Bill & Bob=2C
Thanks for your help. I think I have information at the point to complet
e the antenna and generate some results. I'll plot the SWR graph=2C and ge
t back to you.
Re: the plexiglass. No=2C Bob=2C none of the airplane uses it for=2C fra
nkly=2C anything!! Without you seeing what I'm doing=2C I know it's hard t
o understand what I'm actually building.
The plexiglass I referred to in only a 2" x 2"=2C 3/8" thick block=2C tha
t the antenna is built from. It allows for securing the copper tapes on th
e bottom=2C and a way to bolt the steel mast through it.
I'm sending a photo of essentially what it looks like. I know this photo
is of a halfwave dipole. My plexiglass block is serving a similar functio
n.....just a way to make everything secure. See photo #10 for my similar m
ounting method.
http://forums.matronics.com//files/antenna_design_118.pdf
Mike Welch
_________________________________________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with Hot
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________________________________________________________________________________
| Subject: | is a balun necessary |
| From: | "John Cox" <johnwcox(at)pacificnw.com> |
Mike, can you expound on the process to plot the SWR graph on your
project? Dean Scott's pdf referenced the EZNEC 4.0 plot which was
fascinating.
John Cox
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Mike
Welch
Sent: Friday, April 16, 2010 7:51 AM
Subject: RE: AeroElectric-List: is a balun necessary
Bill & Bob,
Thanks for your help. I think I have information at the point to
complete the antenna and generate some results. I'll plot the SWR
graph, and get back to you.
Re: the plexiglass. No, Bob, none of the airplane uses it for,
frankly, anything!! Without you seeing what I'm doing, I know it's hard
to understand what I'm actually building.
The plexiglass I referred to in only a 2" x 2", 3/8" thick block, that
the antenna is built from. It allows for securing the copper tapes on
the bottom, and a way to bolt the steel mast through it.
I'm sending a photo of essentially what it looks like. I know this
photo is of a halfwave dipole. My plexiglass block is serving a similar
function.....just a way to make everything secure. See photo #10 for my
similar mounting method.
http://forums.matronics.com//files/antenna_design_118.pdf
<http://forums.matronics.com/files/antenna_design_118.pdf>
Mike Welch
________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with
Hotmail. Get busy.
<http://www.windowslive.com/campaign/thenewbusy?tile=multiaccount&ocid=
P
ID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4>
________________________________________________________________________________
| From: | "Jef Vervoort" <jef.vervoortw(at)telenet.be> |
| Subject: | Bussmann fuse blocks |
Bob and all,
I'm interested in using the Bussman fuse block, as suggested in Appendix Z
Note 19.
Where could I find these?
Jef in Belgium, 91031.
________________________________________________________________________________
| Subject: | Re: Bussmann fuse blocks |
| From: | James Kilford <james(at)etravel.org> |
Jef,
I ordered mine from B&C Specialty. Got here in no time (to the UK).
http://www.bandc.biz/circuit-protective-devices.aspx
James
On Fri, Apr 16, 2010 at 4:26 PM, Jef Vervoort wrote:
> Bob and all,
>
>
> Im interested in using the Bussman fuse block, as suggested in Appendix Z
> Note 19.
>
>
> Where could I find these?
>
>
> Jef in Belgium, 91031.
>
>
________________________________________________________________________________
| From: | Peter Pengilly <peter(at)sportingaero.com> |
| Subject: | Re: Bussmann fuse blocks |
Jef,
You could try Vehicle Wiring Products
<http://www.vehicle-wiring-products.eu/VWP-onlinestore/home/homepage.php> in
the UK - should be cheaper than importing from the US.
Peter
On 16/04/2010 16:26, Jef Vervoort wrote:
>
> Bob and all,
>
> I'm interested in using the Bussman fuse block, as suggested in
> Appendix Z Note 19.
>
> Where could I find these?
>
> Jef in Belgium, 91031.
>
> *
>
>
> *
________________________________________________________________________________
| From: | "Dennis & Anne Glaeser" <glaesers(at)wideopenwest.com> |
| Subject: | Designing a circuit question |
I have an in flight adjustable IVO prop. What I'd like to have is a light
that indicates when I get to the flat pitch 'stop' - without adding rings
and brushes.
For those who aren't familiar with the IVO, the adjustment is made by a
motor driving a jack-screw that moves a collar which torques a rod embedded
in the blades. There are no electrical stops, just a rubber washer at each
end of the run. When the collar hits the end, the motor stalls. The rubber
washer provides a softer stall which is a bit easier on the gears driving
the jack screw. A 10A CB is the ultimate 'stop'. Not elegant, but it
works.
On the ground, before starting the engine, it's easy to verify the prop is
in fine pitch by listening to the motor. The problem is before landing,
when I'd like to have the prop in fine pitch, it has to be done by guess and
feel, or just hold the switch until the CB pops - which is not a good thing
to do on a regular basis.
So, what I'd like is a circuit that can sense an amperage spike - going over
9A would be perfect - and turn on a light (LED of course :-) The ramp up to
9A is steep - goes from 5-6A to 9A very quickly (if that helps).
I can build the circuit, I just don't know how to design it.
Thanks in advance,
Dennis Glaeser
________________________________________________________________________________
| From: | David <ainut(at)hiwaay.net> |
| Subject: | Re: Designing a circuit question |
There is a little IC with three pins that you could put in circuit with
the system. It tells you the amperage passing through it. IIRC it's
about $6. I can look up the part number on the ones I have here somewhere...
David M.
Dennis & Anne Glaeser wrote:
>
> I have an in flight adjustable IVO prop. What Id like to have is a
> light that indicates when I get to the flat pitch stop without
> adding rings and brushes.
>
> For those who arent familiar with the IVO, the adjustment is made by
> a motor driving a jack-screw that moves a collar which torques a rod
> embedded in the blades. There are no electrical stops, just a rubber
> washer at each end of the run. When the collar hits the end, the motor
> stalls. The rubber washer provides a softer stall which is a bit
> easier on the gears driving the jack screw. A 10A CB is the ultimate
> stop. Not elegant, but it works.
>
> On the ground, before starting the engine, its easy to verify the
> prop is in fine pitch by listening to the motor. The problem is before
> landing, when Id like to have the prop in fine pitch, it has to be
> done by guess and feel, or just hold the switch until the CB pops
> which is not a good thing to do on a regular basis.
>
> So, what Id like is a circuit that can sense an amperage spike
> going over 9A would be perfect and turn on a light (LED of course
> :-) The ramp up to 9A is steep goes from 5-6A to 9A very quickly (if
> that helps).
>
> I can build the circuit, I just dont know how to design it.
>
> Thanks in advance,
>
> Dennis Glaeser
>
>
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | Designing a circuit question |
Dennis=2C
I have the exact same IvoProp setup. They make an option for this functi
on=2C if I'm not mistaken.
I just went to their website=2C and checked out what they had. They call
it a prop speed govenor. Cost is $320.
Yeah=2C I'd love to build one of these=2C too!! If anyone can come up wi
th a design=2C I could build it!!
Maybe there could be a line of LEDs that reflect the currect load in each
direction of travel.
Mike Welch
From: glaesers(at)wideopenwest.com
Subject: AeroElectric-List: Designing a circuit question
Date: Sat=2C 17 Apr 2010 19:01:38 -0400
I have an in flight adjustable IVO prop. What I=92d like to have is a ligh
t that indicates when I get to the flat pitch =91stop=92 ' without adding
rings and brushes.
For those who aren=92t familiar with the IVO=2C the adjustment is made by a
motor driving a jack-screw that moves a collar which torques a rod embedde
d in the blades. There are no electrical stops=2C just a rubber washer at
each end of the run. When the collar hits the end=2C the motor stalls. Th
e rubber washer provides a softer stall which is a bit easier on the gears
driving the jack screw. A 10A CB is the ultimate =91stop=92. Not elegant
=2C but it works.
On the ground=2C before starting the engine=2C it=92s easy to verify the pr
op is in fine pitch by listening to the motor. The problem is before landi
ng=2C when I=92d like to have the prop in fine pitch=2C it has to be done b
y guess and feel=2C or just hold the switch until the CB pops ' which is
not a good thing to do on a regular basis.
So=2C what I=92d like is a circuit that can sense an amperage spike ' goi
ng over 9A would be perfect ' and turn on a light (LED of course :-) The
ramp up to 9A is steep ' goes from 5-6A to 9A very quickly (if that help
s).
I can build the circuit=2C I just don=92t know how to design it.
Thanks in advance=2C
Dennis Glaeser
_________________________________________________________________
The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with H
otmail.
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PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5
________________________________________________________________________________
| From: | "Dennis & Anne Glaeser" <glaesers(at)wideopenwest.com> |
| Subject: | RE: Designing a circuit question |
Mike,
I've seen their speed governor on their website, but don't know how well it
works. Making a decent speed controller is more involved and expensive than
I want.
All I really want is a 'limit sensor' for the pitch stops.
Some IVO owners have installed an ammeter, which is an option but I'm hoping
for something simpler - just a light.
Dennis
----------
Mike Welch (mdnanwelch7(at)hotmail.com)
Date:
Sat Apr 17 - 5:54 PM
Dennis
I have the exact same IvoProp setup. They make an option for this
function if I'm not mistaken.
I just went to their website and checked out what they had. They call it
a prop speed govenor. Cost is $320.
Yeah I'd love to build one of these too!! If anyone can come up with a
design I could build it!!
Maybe there could be a line of LEDs that reflect the currect load in each
direction of travel.
Mike Welch
________________________________________________________________________________
| From: | "Dennis & Anne Glaeser" <glaesers(at)wideopenwest.com> |
| Subject: | RE: Designing a circuit question |
David,
Can the IC do any switching based on the amperage it senses?
Dennis
------------------
From: David (ainut(at)hiwaay.net)
There is a little IC with three pins that you could put in circuit with
the system. It tells you the amperage passing through it. IIRC it's
about $6. I can look up the part number on the ones I have here somewhere...
David M.
________________________________________________________________________________
| From: | David <ainut(at)hiwaay.net> |
| Subject: | Re: RE: Designing a circuit question |
Not this one. That would have to be another circuit. A $1
microprossesser could handle a $17 relay to do that job.
David
Dennis & Anne Glaeser wrote:
> --> AeroElectric-List message posted by: "Dennis& Anne Glaeser"
>
> David,
>
> Can the IC do any switching based on the amperage it senses?
>
> Dennis
>
> ------------------
> From: David (ainut(at)hiwaay.net)
>
> There is a little IC with three pins that you could put in circuit with
> the system. It tells you the amperage passing through it. IIRC it's
> about $6. I can look up the part number on the ones I have here somewhere...
>
> David M.
>
>
>
________________________________________________________________________________
| From: | "Peter W Johnson" <vk3eka(at)bigpond.net.au> |
| Subject: | Zeftronics G1200N |
Hi Guys,
I am presently trouble shooting a newly installed regulator on an O-200.
I have measured all the resistances and all seem OK.
When I connect everything up and turn on the Bat and Fld switches (engine
off) I get the three lights, GO, VR, and CL all on but the CL light is red
not green. Is this a problem?
Presently the Gen Out Light doesn't seem to go out until around 1800 rpm. I
assume from the zeftronics documents that this should go out at between 1100
rpm and 1400 rpm.
Any advice would be good.
Cheers
Peter
Wonthaggi Australia
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Zeftronics G1200N |
Good Morning Peter,
A couple of years ago I was having trouble getting a Zeftronics unit to
operate the way I thought it should. Just as you have done, I measured the
resistance of various components and all checked out fine. When I called
Zeftronics, they told me to check the actual voltage while the system was
operating. I attached appropriate wiring to the points they suggested so
that I
could get the data they wanted with the engine running. In fact, I checked
it in flight.
I found that even though several components checked out OK with my Ohmmete
r
when static, there were inappropriate voltage drops when in operation. I
changed a circuit breaker and a field switch in the circuit and all my
problems went away. That may have nothing to do with your problem, but it
taught
me that the system needs to be checked when it is under load.
For What It Is Worth, I have installed Zeftronics Alternator Control Units
in three airplanes thus far and have been very pleased with them all. The
folks at the factory have answered my questions patiently and fully.
Happy Skies,
Old Bob
In a message dated 4/18/2010 4:04:44 A.M. Central Daylight Time,
vk3eka(at)bigpond.net.au writes:
Hi Guys,
I am presently trouble shooting a newly installed regulator on an O-200.
I have measured all the resistance and all seem OK.
When I connect everything up and turn on the Bat and Fld switches (engine
off) I get the three lights, GO, VR, and CL all on but the CL light is re
d
not green. Is this a problem?
Presently the Gen Out Light doesn=99t seem to go out until around
1800 rpm.
I assume from the zeftronics documents that this should go out at between
1100 rpm and 1400 rpm.
Any advice would be good.
Cheers
Peter
Wonthaggi Australia
========================
============
(http://www.matronics.com/Navigator?AeroElectric-List)
========================
============
========================
============
(http://www.matronics.com/contribution)
========================
============
________________________________________________________________________________
| Subject: | Re: Designing a circuit question |
| From: | "user9253" <fran4sew(at)banyanol.com> |
Dennis,
How about this circuit designed by Bob N?
http://www.aeroelectric.com/articles/Failure_Detection_and_Annunciation.pdf
You would have to experiment with the number of turns of wire to wrap around the
reed relay. I have reed switches and can bring one to the EAA meeting if you
need it.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294643#294643
________________________________________________________________________________
I realize this is more avionics then electrics, but this place is my prim
ary resource.
After a small building hiatus, I am back on wiring my panel.
the 300 xl has MIC Audio hi and Low as possible inputs.
The AVCOM AC6PA intercom has a MIC to Radio output, but I cannot find:
output levels at that MIC to radio connector in the AVCOM book.
input levels listed in the 300XL installation for either input.
Anybody have the answer or an additional resource to review?
Jim Timoney
Searey 80% done, 90% to go
________________________________________________________________________________
| From: | Ron Quillin <rjquillin(at)gmail.com> |
I see this morning Amazon has a gold box special on Powergenix 1.6V
rechargeable batteries.
http://www.amazon.com/gp/goldbox/ref=cs_top_nav_gb27
A recharger and 4 AA for $15.
http://www.powergenix.com/products.php
Their faq
http://www.powergenix.com/faq.php
Is pretty generic, but does have a few tidbits. From reading the list, I
should know what self-discharge rates are for other batteries, and my gray
is showing, but they cite *PowerGenix batteries have a self-discharge rate
equal of approximately 8 percent per month at room temperature. This is
comparable to other rechargeable batteries. *
I'm tempted to try them out for cameras and GPS units.
Anyone with any experience?
I'm sure there will be comments...
Ron Q.
________________________________________________________________________________
| From: | "Peter W Johnson" <vk3eka(at)bigpond.net.au> |
| Subject: | Zeftronics G1200N |
Bob,
Thanks, did you ever get a copy of the fault light codes?
Looks like I=99ll have to do a little more testing.
Cheers
Peter
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
BobsV35B(at)aol.com
Sent: Sunday, 18 April 2010 10:02 PM
Subject: Re: AeroElectric-List: Zeftronics G1200N
Good Morning Peter,
A couple of years ago I was having trouble getting a Zeftronics unit to
operate the way I thought it should. Just as you have done, I measured
the resistance of various components and all checked out fine. When I
called Zeftronics, they told me to check the actual voltage while the
system was operating. I attached appropriate wiring to the points they
suggested so that I could get the data they wanted with the engine
running. In fact, I checked it in flight.
I found that even though several components checked out OK with my
Ohmmeter when static, there were inappropriate voltage drops when in
operation. I changed a circuit breaker and a field switch in the circuit
and all my problems went away. That may have nothing to do with your
problem, but it taught me that the system needs to be checked when it is
under load.
For What It Is Worth, I have installed Zeftronics Alternator Control
Units in three airplanes thus far and have been very pleased with them
all. The folks at the factory have answered my questions patiently and
fully.
Happy Skies,
Old Bob
In a message dated 4/18/2010 4:04:44 A.M. Central Daylight Time,
vk3eka(at)bigpond.net.au writes:
Hi Guys,
I am presently trouble shooting a newly installed regulator on an O-200.
I have measured all the resistance and all seem OK.
When I connect everything up and turn on the Bat and Fld switches
(engine off) I get the three lights, GO, VR, and CL all on but the CL
light is red not green. Is this a problem?
Presently the Gen Out Light doesn=99t seem to go out until around
1800 rpm. I assume from the zeftronics documents that this should go out
at between 1100 rpm and 1400 rpm.
Any advice would be good.
Cheers
Peter
Wonthaggi Australia
List
href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.
matronics.com/Navigator?AeroElectric-List
ms.matronics.com/">http://forums.matronics.com
tp://www.matronics.com/contribution">http://www.matronics.com/contributio
n
________________________________________________________________________________
| Subject: | Re: Accurate Altitude and Airspeed |
| From: | Sam Hoskins <sam.hoskins(at)gmail.com> |
This is great information about the static ports. I recently switched from
steam gauges to a Dynon FlightDek. One of the neatest features is the winds
aloft display. Unfortunately, I figured out that it was pretty inaccurate.
One day, I went up and flew four headings and this is what got:
Compass Wind Direction Wind Speed
360 242 20
270 334 18
180 251 31
090 271 08
This told me the display was pretty much worthless. I posted s couple of
notes about it on the Dynon factory forum and was told to look after my
static ports, but no indication how to go about it.
I will definitely be investigating the wedges at the static ports.
Thanks.
Sam Hoskins
Murphysboro, IL
On Thu, Apr 15, 2010 at 5:06 PM, wrote:
>
> 4/15/2010
>
> Hello Mike, You wrote: "Not sure why this (altitude variation with
> airspeed)
> would be, or more importantly, how to fix it."
>
> Hello Bernie, You wrote: "There didn't seem to be any theory behind it."
>
> This is not a very rare or mysterious phenomena. Inaccurate airspeed
> indications can be caused by inaccurate dynamic and static air pressure
> forces. Inaccurate altitude indications can be caused by inaccurate static
> pressure forces.
>
> AIRSPEED. Let's talk about inaccurate airspeed measurements first. An
> airspeed indicator is a balancing mechanism. It balances the difference
> between a force created by dynamic air pressure and a force created by
> static air pressure. The force from the dynamic air pressure is the result
> of the forward movement of the airplane. The faster the airplane moves the
> greater the force exerted.
>
> In order to get an accurate measure of that dynamic force one needs to
> accurately sense the free stream dynamic air pressure and send it to the
> airspeed indicator via leak and kink free tubing. That means sensing the
> air
> movement in the actual direction that the airplane is moving and having
> that
> air movement not affected by some local air flow direction change caused by
> the airframe itself. This is why you sometimes see flight test airplanes
> with a long boom sticking out forward with a small vane mechanism on the
> front of it. This boom and vane mechanism, along with connecting tubing, is
> a pitot tube system intended to accurately measure the force from the free
> stream dynamic air pressure without any inaccuracies introduced by local
> airframe air flow. See Note One below.
>
> So much for the dynamic force side of the airspeed indicator balancing act,
> what about the static force side? An accurate static force is provided by a
> static port ideally located somewhere on the airframe such that it is
> measuring the true static air pressure. But finding that ideal location and
> making the perfect static port that does not introduce static air pressure
> errors is not always so quick and easy. And what do we do if we discover
> that the static port that we have installed is not producing accurate
> static
> air pressure? See Note Two below.
>
> ALTITUDE. An altimeter is also a balancing mechanism. It measures the
> difference between the initial altitude setting of the altimeter mechanism
> as compared to the static air pressure encountered by that same mechanism
> while in flight and displays that difference in some lineal measurement
> (usually in feet in our part of the world). If the static pressure provided
> to the altimeter via the static port and the connecting tubing is in error
> or changes with the airplane's airspeed, when the actual altitude is
> constant, then the altimeter's altitude indication will be in error. And
> what do we do if we discover that the static port that we have installed is
> not producing accurate static air pressure? See Note Two below.
>
> 'OC' Says: "The best investment we can make is the effort to gather and
> understand knowledge."
>
> Note One: Why don't we use these long boom and vane type pitot tubes on our
> experimental amateur built aircraft? Because the boom and vane would take a
> terrific beating from people walking into them on the ground and because
> the
> dynamic force errors introduced by the type of pitot tubes that we commonly
> use are just not great enough to cause us concern. There is not very much
> we
> can do about adjusting the force coming from dynamic air pressure other
> than
> using a pitot tube located a sufficient distance from a disturbing piece of
> airframe (usually the bottom surface of a wing) and avoiding a leak or kink
> in the tubing going from the pitot tube to the airspeed indicator.
>
> Note Two: So we have built our airplane, installed our static port(s), and
> discovered that we are getting inaccurate airspeed and / or altitude
> indications and decide to do something about it. We could just go on
> installing new static ports in different locations, but that is a lot of
> work and we are not assured of better results. So we should do just what
> the
> big boy aerodynamic types do, we fudge or bandaid as needed to get the air
> to give us the results that we want.
>
> Let's say that the airspeed indicator is reading too high -- it says the
> airplane is going faster than it really is. (See Note Three). The dynamic
> air pressure side of the airspeed indicator is providing too much force in
> the desired balancing act. How can we counteract that excess dynamic force?
> We increase the static force being fed to the airspeed instrument by the
> static port by installing a small wedge just aft of the opening on the
> static port (thin edge of the wedge facing forward towards the hole). This
> small wedge causes air to pile up and increase the static air pressure
> going
> to the airspeed indicator (and also to the altimeter unless you have
> provided separate static ports for the two instruments) and give us the
> accurate force balance measurement that we want.
>
> Let's say that the altimeter reading goes down 200 feet when you speed up
> 60
> miles per hour (Mike, you did not say which direction your altitude was
> changing with the changes in airspeed). This means that the static port is
> feeding greater than static pressure as your airplane flies faster. How can
> we reduce that undesired increase in static air pressure? We install a
> small
> wedge in front of the hole in the static port (thin edge of the wedge
> facing
> aft towards the hole) to shield it a bit from dynamic air pressure coming
> from the front in order to get a more stable and accurate altitude reading.
>
> How do we get the right size wedge facing the correct direction to get the
> airspeed and altitude results that we want? The same way the big boys do:
> TRIAL AND ERROR and MORE TRIAL AND ERROR. Because our airplanes are
> experimental, amateur built we are permitted to do just that -- experiment.
>
> Note Three: So now we know how to tweak our static port(s) to give us
> accurate airspeed and altitude information, but how do we know that the
> airspeed and altitude information is inaccurate in the first place and
> during our trial and error efforts how do we know when we have achieved the
> accuracy that we are seeking? The answer to those two questions is not as
> simple as one might first expect. I won't attempt to answer them here
> because the answers are too big and complex to answer in this forum. What I
> will suggest is that the reader google "accurate airspeed" and "accurate
> altitude" and delve into those subjects to the level desired. Here is just
> one source you will find:
>
> http://gpsinformation.net/main/altitude.htm
>
> Note Four: This is a personal view point. There are several methods
> available for determining accurate true airspeed. Some rather elaborate --
> some use GPS. Just google "accurate airspeed using GPS".
>
> One thing that I've never quite understood regarding these methods is the
> focus on precisely determining airspeed accuracy indication in the cruising
> airspeed range. If I determine that my airspeed indicator shows 150 knots
> indicated airspeed and I determine through some elaborate scheme that I am
> actually only going 145 knots through the air what do I do with that
> information? Being 5 nautical miles short of my destination after a one
> hour
> flight is a trivial naviagation error contribution compared to all the
> other
> error sources (such as heading, wind, and climb airspeed) that I have to
> contend with and should overcome anyway by some means of real time enroute
> navigation.
>
> I think that if I were going to invest a lot of time and effort in
> determining my exact airspeed error I would be inclined to do that
> determination in the approach airspeed arena, not the cruising airspeed
> arena. And even then I would not be obsessed with absolute airspeed
> accuracy, I'd just want to know what number on the indicator gives me the
> right kind of safe approach and landing time after time.
>
> ================================================
>
> ----- Original Message ----- From: <bwilder(at)tqci.net>
> To: "Keith Palmer"
> Cc: "mike mccann" ; "Pulsar builders"
>
> Sent: Thursday, April 15, 2010 9:18 AM
> Subject: Re: Here's an odd question
>
>
> I noticed that the back half of the round washer where the static exits on
>> the SR22 had the back half of it filed down so there was in effect a
>> little shield protecting the static exit hole. ((Sorry about this
>> description.)
>>
>> I asked the people at their booth why they did that. I think I attended
>> four air shows before I found someone who was involved with the
>> engineering of the system. The answer - - - - "That is what we had to do
>> to make the system work right". There didn't seem to be any theory behind
>> it. They indicated that they had to fiddle around to get it to behave the
>> way they wanted. Maybe they were just trying to get rid of me.
>>
>> In any event, I did the same with mine and it works fine.
>>
>> Bernie Wilder
>>
>
> =============================================
>
>>
>>> ----- Original Message -----
>>> From: mike mccann
>>> To: Pulsar builders
>>> Sent: Thursday, April 15, 2010 5:06 AM
>>> Subject: Here's an odd question
>>>
>>>
>>> All,
>>>
>>> Utilizing a GPS, I've found that my altimeter in my Pulsar varies with
>>> changes in airspeed (altitude will change 100-200 feet with speed
>>> changes of 60 mph).
>>>
>>> Has anyone ever heard of this. Not sure why this would be, or more
>>> importantly, how to fix it.
>>>
>>> Many thanks,
>>>
>>> Mike
>>>
>>> Pulsar 1
>>> N116Km
>>>
>>
>
>
________________________________________________________________________________
| From: | Doug Ilg <doug.ilg(at)verizon.net> |
| Subject: | Re: RE: Designing a circuit question |
Just to be clear, if all you want to do is light an LED (the original plan), there's
no need for a relay. Any of those $1 microprocessors should be able to
drive a normal LED directly off an output pin. Of course, if you're going to
the trouble of putting together this sort of circuit, making it control a relay
to take the power off the motor would be a fairly easy add-on.
Doug Ilg
Grumman Tiger N74818, College Park Airport (KCGS), Maryland
Challenger II LSS LW (N641LG reserved) - kit underway at Laurel Suburban (W18)
----- Original Message ----
> From: David <ainut(at)hiwaay.net>
> To: aeroelectric-list(at)matronics.com
> Sent: Sun, April 18, 2010 12:41:29 AM
> Subject: Re: AeroElectric-List: RE: Designing a circuit question
>
> Not this one. That would have to be another circuit. A $1 microprossesser
> could handle a $17 relay to do that job.
>
> David
________________________________________________________________________________
| From: | "Floyd Wilkes" <fwilkes(at)gvtc.com> |
| Subject: | Accurate Altitude and Airspeed |
Sam,
In order for the Dynon to get the correct wind, it must have a accurate
indicated airspeed.
I do not know what you are flying, but the Zenith 601XL with standard pitot
static setup is very inaccurate at cruise speeds.
Check what your indicated vs calibrated speeds are and If possible adjust
to get the indicated very close to calibrated at your cruise speed.
Floyd Wilkes
601XL
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Sam
Hoskins
Sent: Sunday, April 18, 2010 9:43 AM
Subject: Re: AeroElectric-List: Accurate Altitude and Airspeed
This is great information about the static ports. I recently switched from
steam gauges to a Dynon FlightDek. One of the neatest features is the winds
aloft display. Unfortunately, I figured out that it was pretty inaccurate.
One day, I went up and flew four headings and this is what got:
Compass Wind Direction Wind Speed
360 242 20
270 334 18
180 251 31
090 271 08
This told me the display was pretty much worthless. I posted s couple of
notes about it on the Dynon factory forum and was told to look after my
static ports, but no indication how to go about it.
I will definitely be investigating the wedges at the static ports.
Thanks.
Sam Hoskins
Murphysboro, IL
On Thu, Apr 15, 2010 at 5:06 PM, wrote:
4/15/2010
Hello Mike, You wrote: "Not sure why this (altitude variation with airspeed)
would be, or more importantly, how to fix it."
Hello Bernie, You wrote: "There didn't seem to be any theory behind it."
This is not a very rare or mysterious phenomena. Inaccurate airspeed
indications can be caused by inaccurate dynamic and static air pressure
forces. Inaccurate altitude indications can be caused by inaccurate static
pressure forces.
AIRSPEED. Let's talk about inaccurate airspeed measurements first. An
airspeed indicator is a balancing mechanism. It balances the difference
between a force created by dynamic air pressure and a force created by
static air pressure. The force from the dynamic air pressure is the result
of the forward movement of the airplane. The faster the airplane moves the
greater the force exerted.
In order to get an accurate measure of that dynamic force one needs to
accurately sense the free stream dynamic air pressure and send it to the
airspeed indicator via leak and kink free tubing. That means sensing the air
movement in the actual direction that the airplane is moving and having that
air movement not affected by some local air flow direction change caused by
the airframe itself. This is why you sometimes see flight test airplanes
with a long boom sticking out forward with a small vane mechanism on the
front of it. This boom and vane mechanism, along with connecting tubing, is
a pitot tube system intended to accurately measure the force from the free
stream dynamic air pressure without any inaccuracies introduced by local
airframe air flow. See Note One below.
So much for the dynamic force side of the airspeed indicator balancing act,
what about the static force side? An accurate static force is provided by a
static port ideally located somewhere on the airframe such that it is
measuring the true static air pressure. But finding that ideal location and
making the perfect static port that does not introduce static air pressure
errors is not always so quick and easy. And what do we do if we discover
that the static port that we have installed is not producing accurate static
air pressure? See Note Two below.
ALTITUDE. An altimeter is also a balancing mechanism. It measures the
difference between the initial altitude setting of the altimeter mechanism
as compared to the static air pressure encountered by that same mechanism
while in flight and displays that difference in some lineal measurement
(usually in feet in our part of the world). If the static pressure provided
to the altimeter via the static port and the connecting tubing is in error
or changes with the airplane's airspeed, when the actual altitude is
constant, then the altimeter's altitude indication will be in error. And
what do we do if we discover that the static port that we have installed is
not producing accurate static air pressure? See Note Two below.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
Note One: Why don't we use these long boom and vane type pitot tubes on our
experimental amateur built aircraft? Because the boom and vane would take a
terrific beating from people walking into them on the ground and because the
dynamic force errors introduced by the type of pitot tubes that we commonly
use are just not great enough to cause us concern. There is not very much we
can do about adjusting the force coming from dynamic air pressure other than
using a pitot tube located a sufficient distance from a disturbing piece of
airframe (usually the bottom surface of a wing) and avoiding a leak or kink
in the tubing going from the pitot tube to the airspeed indicator.
Note Two: So we have built our airplane, installed our static port(s), and
discovered that we are getting inaccurate airspeed and / or altitude
indications and decide to do something about it. We could just go on
installing new static ports in different locations, but that is a lot of
work and we are not assured of better results. So we should do just what the
big boy aerodynamic types do, we fudge or bandaid as needed to get the air
to give us the results that we want.
Let's say that the airspeed indicator is reading too high -- it says the
airplane is going faster than it really is. (See Note Three). The dynamic
air pressure side of the airspeed indicator is providing too much force in
the desired balancing act. How can we counteract that excess dynamic force?
We increase the static force being fed to the airspeed instrument by the
static port by installing a small wedge just aft of the opening on the
static port (thin edge of the wedge facing forward towards the hole). This
small wedge causes air to pile up and increase the static air pressure going
to the airspeed indicator (and also to the altimeter unless you have
provided separate static ports for the two instruments) and give us the
accurate force balance measurement that we want.
Let's say that the altimeter reading goes down 200 feet when you speed up 60
miles per hour (Mike, you did not say which direction your altitude was
changing with the changes in airspeed). This means that the static port is
feeding greater than static pressure as your airplane flies faster. How can
we reduce that undesired increase in static air pressure? We install a small
wedge in front of the hole in the static port (thin edge of the wedge facing
aft towards the hole) to shield it a bit from dynamic air pressure coming
from the front in order to get a more stable and accurate altitude reading.
How do we get the right size wedge facing the correct direction to get the
airspeed and altitude results that we want? The same way the big boys do:
TRIAL AND ERROR and MORE TRIAL AND ERROR. Because our airplanes are
experimental, amateur built we are permitted to do just that -- experiment.
Note Three: So now we know how to tweak our static port(s) to give us
accurate airspeed and altitude information, but how do we know that the
airspeed and altitude information is inaccurate in the first place and
during our trial and error efforts how do we know when we have achieved the
accuracy that we are seeking? The answer to those two questions is not as
simple as one might first expect. I won't attempt to answer them here
because the answers are too big and complex to answer in this forum. What I
will suggest is that the reader google "accurate airspeed" and "accurate
altitude" and delve into those subjects to the level desired. Here is just
one source you will find:
http://gpsinformation.net/main/altitude.htm
Note Four: This is a personal view point. There are several methods
available for determining accurate true airspeed. Some rather elaborate --
some use GPS. Just google "accurate airspeed using GPS".
One thing that I've never quite understood regarding these methods is the
focus on precisely determining airspeed accuracy indication in the cruising
airspeed range. If I determine that my airspeed indicator shows 150 knots
indicated airspeed and I determine through some elaborate scheme that I am
actually only going 145 knots through the air what do I do with that
information? Being 5 nautical miles short of my destination after a one hour
flight is a trivial naviagation error contribution compared to all the other
error sources (such as heading, wind, and climb airspeed) that I have to
contend with and should overcome anyway by some means of real time enroute
navigation.
I think that if I were going to invest a lot of time and effort in
determining my exact airspeed error I would be inclined to do that
determination in the approach airspeed arena, not the cruising airspeed
arena. And even then I would not be obsessed with absolute airspeed
accuracy, I'd just want to know what number on the indicator gives me the
right kind of safe approach and landing time after time.
=======================
----- Original Message ----- From: <bwilder(at)tqci.net>
Cc: "mike mccann" ; "Pulsar builders"
Sent: Thursday, April 15, 2010 9:18 AM
Subject: Re: Here's an odd question
I noticed that the back half of the round washer where the static exits on
the SR22 had the back half of it filed down so there was in effect a
little shield protecting the static exit hole. ((Sorry about this
description.)
I asked the people at their booth why they did that. I think I attended
four air shows before I found someone who was involved with the
engineering of the system. The answer - - - - "That is what we had to do
to make the system work right". There didn't seem to be any theory behind
it. They indicated that they had to fiddle around to get it to behave the
way they wanted. Maybe they were just trying to get rid of me.
In any event, I did the same with mine and it works fine.
Bernie Wilder
====================
----- Original Message -----
From: mike mccann
To: Pulsar builders
Sent: Thursday, April 15, 2010 5:06 AM
Subject: Here's an odd question
All,
Utilizing a GPS, I've found that my altimeter in my Pulsar varies with
changes in airspeed (altitude will change 100-200 feet with speed
changes of 60 mph).
Has anyone ever heard of this. Not sure why this would be, or more
importantly, how to fix it.
Many thanks,
Mike
Pulsar 1
N116Km
==========
-List" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
==========
http://forums.matronics.com
==========
le, List Admin.
="_blank">http://www.matronics.com/contribution
==========
________________________________________________________________________________
| Subject: | Re: Accurate Altitude and Airspeed |
| From: | Kevin Horton <khorton01(at)rogers.com> |
On 2010-04-15, at 18:06 , wrote:
> One thing that I've never quite understood regarding these methods is the
> focus on precisely determining airspeed accuracy indication in the cruising
> airspeed range. If I determine that my airspeed indicator shows 150 knots
> indicated airspeed and I determine through some elaborate scheme that I am
> actually only going 145 knots through the air what do I do with that
> information? Being 5 nautical miles short of my destination after a one hour
> flight is a trivial naviagation error contribution compared to all the other
> error sources (such as heading, wind, and climb airspeed) that I have to
> contend with and should overcome anyway by some means of real time enroute
> navigation.
>
> I think that if I were going to invest a lot of time and effort in
> determining my exact airspeed error I would be inclined to do that
> determination in the approach airspeed arena, not the cruising airspeed
> arena. And even then I would not be obsessed with absolute airspeed
> accuracy, I'd just want to know what number on the indicator gives me the
> right kind of safe approach and landing time after time.
As you note, an accurate airspeed indication is not really that important, looked
at in isolation. Even if there is a significant error at approach speeds,
it is not so important as long as the error is the same on every flight. Determining
what IAS our aircraft needs for a safe, effective approach and landing
is one of the many things we will do during the flight test phase.
But, with modern avionics, many EFIS systems calculate TAS based on IAS, altitude
and temperature, and use that in conjunction with GPS track and groundspeed
to calculate wind. They then put a nice little wind vector on the display, and
it bugs the heck out of folks if the wind info is wrong.
The most important aspect of static system errors is not the effect on IAS. The
important aspect is the effect on the altimeter accuracy. It is quite possible
to have static system position errors that will give over 100 ft error in
the altimeter at cruise airspeeds. If we are flying at our VFR cruising altitude,
and there is IFR traffic that is supposed to be 500 ft above or below us,
errors in our static system can become significant. If we have 100 ft of static
system error, plus each aircraft has 50 ft of altimeter instrument error,
plus perhaps we are not on quite the right altimeter setting because we aren't
using flight following, and each pilot is 50 ft high or low from his nominal
indicated altitude, these errors may add up. It is quite conceivable that aircraft
that are supposed to be 500 ft apart may turn out to be a have less than
200 ft of altitude separation. If we are flying IFR approaches in IMC, the
effect of static system position error on our altimeter is important to know.
--
Kevin Horton
RV-8
Ottawa, Canada
http://www.kilohotel.com/rv8
________________________________________________________________________________
| From: | "J. Mcculley" <mcculleyja(at)starpower.net> |
| Subject: | Re: Crowbar OV module part |
Phil: I sent you an off-list response on your MBS 4991 problem using
your aol address on 4/11. If you did not receive it and would like to,
let me know off list at mcculleyja(at)starpower.net.
JIM
=========================================================================
Phil wrote:
>
> Bob: The part listed as "MBS4991" is no longer carried by Digi-Key.
> Mouser lists a possible replacement as a silicon bi-lateral switch by
> NTE as their part NTE6403. Is this the correct type item? Or is that
> device something else?
>
> Need to build 2 OV modules for my electrically dependent, dual
> alternator project.
>
> Phil
> RV-10 w/ Mazda 20B rotary engine in IL
============================================================================
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
On 4/18/2010 8:52 AM, jtortho(at)aol.com wrote:
>
> I realize this is more avionics then electrics, but this place is my
> primary resource.
>
> After a small building hiatus, I am back on wiring my panel.
>
> the 300 xl has MIC Audio hi and Low as possible inputs.
>
> The AVCOM AC6PA intercom has a MIC to Radio output, but I cannot find:
>
> output levels at that MIC to radio connector in the AVCOM book.
>
> input levels listed in the 300XL installation for either input.
>
>
> Anybody have the answer or an additional resource to review?
>
> Jim Timoney
> Searey 80% done, 90% to go
Hi Jim,
Typically, the 'hi' & 'low' in aviation radio/intercom terminology
refers to signal (hi) and return path (low), rather than different
levels. I'd expect the intercom's mic to radio terminal to go to the mic
hi terminal on the radio. I'd expect the mic low terminal to connect to
the intercom's 'low' or 'ground' or 'return', etc; depending on AVCOM's
terminology.
Hope that helps.
Charlie
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Zeftronics G1200N |
Good Afternoon Peter,
To tell you the truth, I don't remember. I kinda think they were mentioned
,
but have no recollection of the manner.
Happy Skies,
Old Forgetful Bob
In a message dated 4/18/2010 9:27:17 A.M. Central Daylight Time,
vk3eka(at)bigpond.net.au writes:
Bob,
Thanks, did you ever get a copy of the fault light codes?
Looks like I=99ll have to do a little more testing.
Cheers
Peter
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Designing a circuit question |
At 06:01 PM 4/17/2010, you wrote:
>I have an in flight adjustable IVO prop. What
>Id like to have is a light that indicates when
>I get to the flat pitch stop without adding rings and brushes.
>For those who arent familiar with the IVO, the
>adjustment is made by a motor driving a
>jack-screw that moves a collar which torques a
>rod embedded in the blades. There are no
>electrical stops, just a rubber washer at each
>end of the run. When the collar hits the end,
>the motor stalls. The rubber washer provides a
>softer stall which is a bit easier on the gears
>driving the jack screw. A 10A CB is the
>ultimate stop. Not elegant, but it works.
>On the ground, before starting the engine, its
>easy to verify the prop is in fine pitch by
>listening to the motor. The problem is before
>landing, when Id like to have the prop in fine
>pitch, it has to be done by guess and feel, or
>just hold the switch until the CB pops which
>is not a good thing to do on a regular basis.
>So, what Id like is a circuit that can sense an
>amperage spike going over 9A would be perfect
> and turn on a light (LED of course :-) The
>ramp up to 9A is steep goes from 5-6A to 9A very quickly (if that helps).
>I can build the circuit, I just dont know how to design it.
The reed switch sensor Joe mentioned is worthy of further
thought. You could also build a simple constant current
generator set for something less than the CB trip current.
By watching for the voltage to spike across the generator
could light an LED to indicate end-of-travel and stop using
the CB as an operating indicator.
I'm just getting ready to head for Wichita but I'll noodle
the idea on the way up. I can perhaps publish something later
this evening.
Bob . . .
________________________________________________________________________________
| From: | "Bill Bradburry" <bbradburry(at)bellsouth.net> |
| Subject: | how to wire an electret microphone |
I am considering trying to build a headphone for my plane. Can someone tell
me how to wire an electret microphone like the one below so that it can be
plugged into the planes jack?
http://www.radioshack.com/product/index.jsp?productId 62216
You can safely assume that I am dumb enough to try this with absolutely no
knowledge of how to do it and would need a very good explanation.
Something like, "just use a condenser.", will not help me much. :>)
Bill B
________________________________________________________________________________
| From: | "Dennis & Anne Glaeser" <glaesers(at)wideopenwest.com> |
| Subject: | Re: RE: Designing a circuit question |
Doug,
It may be clear to you, but you've got to do better than that to be clear to
me :-)
I understand the concept, but need a circuit diagram, and which $1
microprocessor to use.
I agree that once I know how to turn the LED on, adding a relay is straight
forward. Have to admit I hadn't thought of that. I have to think about it
and decide if it is worth the extra complexity and parts - vs. just me just
letting go of the switch...
Dennis
----------------------
Just to be clear, if all you want to do is light an LED (the original plan),
there's
no need for a relay. Any of those $1 microprocessors should be able to
drive a normal LED directly off an output pin. Of course, if you're going
to
the trouble of putting together this sort of circuit, making it control a
relay
to take the power off the motor would be a fairly easy add-on.
Doug Ilg
________________________________________________________________________________
| From: | Doug Ilg <doug.ilg(at)verizon.net> |
| Subject: | Re: RE: Designing a circuit question |
Dennis,
I'm not really the right person to give lessons on microprocessors. All that I've
done is to implement simple schematics and programs that I found on the 'net.
(A quick search for "PIC16" should find some sites with projects for that
popular line of microprocessors.) I know from that that you can drive an LED
directly off an output pin with an appropriate resistor.
My point was to tell you that the relay that was referred to is not necessary for
your original purpose (to light an LED). It would be useful to actually interrupt
current to the motor, if you chose to do that.
Maybe the person who originally suggested using a microprocessor can give you better
advice on how to use those.
Doug Ilg
Grumman Tiger N74818, College Park Airport (KCGS), Maryland
Challenger II LSS LW (N641LG reserved) - kit underway at Laurel Suburban (W18)
----- Original Message ----
> From: Dennis & Anne Glaeser <glaesers(at)wideopenwest.com>
> To: aeroelectric-list(at)matronics.com
> Sent: Sun, April 18, 2010 6:42:02 PM
> Subject: AeroElectric-List: Re: RE: Designing a circuit question
Doug,
It
> may be clear to you, but you've got to do better than that to be clear to
me
> :-)
I understand the concept, but need a circuit diagram, and which
> $1
microprocessor to use.
I agree that once I know how to turn the LED on,
> adding a relay is straight
forward. Have to admit I hadn't thought of
> that. I have to think about it
and decide if it is worth the extra
> complexity and parts - vs. just me just
letting go of the
> switch...
________________________________________________________________________________
| From: | "David LLoyd" <skywagon(at)charter.net> |
| Subject: | Re: how to wire an electret microphone |
Bill,
With good headphones so cheap, especially 2nd hand, I don't know why you
would want to do this. Especially since all the deep pocket guys have
tossed over their faithful ANR headsets for the Bose and Zulu models.
However,... the first thing is to probably consider is the type of mike
element. It has to deal with cancelling most of the back ground noise.
I am guessing the RS mike element may not qualify as a noise cancelling
mike....
David
-------------------------------------------------------------------------
-------
----- Original Message -----
From: Bill Bradburry
To: aeroelectric-list(at)matronics.com
Sent: Sunday, April 18, 2010 12:59 PM
Subject: AeroElectric-List: how to wire an electret microphone
I am considering trying to build a headphone for my plane. Can
someone tell me how to wire an electret microphone like the one below so
that it can be plugged into the planes jack?
http://www.radioshack.com/product/index.jsp?productId 62216
You can safely assume that I am dumb enough to try this with
absolutely no knowledge of how to do it and would need a very good
explanation.
Something like, "just use a condenser.", will not help me much. :>)
Bill B
________________________________________________________________________________
| From: | <robert.mccallum2(at)sympatico.ca> |
| Subject: | Re: how to wire an electret microphone |
Bill=3B
Trying to build headphones for the exercise of doing could certainly be par
t of the learning experience if you have the time available=2C however=2C y
ou might want to check the product reviews found on the link you provided.
The description says this is an "Electret Mic" but one of the reviews point
s out that in fact it is actually a "Condenser Mic". I don't know the signi
ficance of that discrepancy=2C but it is something you might want to note.
Bob McC
Bill=2C
With good headphones so cheap=2C especially 2nd hand=2C I don't know why yo
u would want to do this. Especially since all the deep pocket guys have to
ssed over their faithful ANR headsets for the Bose and Zulu models.
However=2C... the first thing is to probably consider is the type of mike e
lement. It has to deal with cancelling most of the back ground noise. I a
m guessing the RS mike element may not qualify as a noise cancelling mike..
..
David
----- Original Message -----
From: Bill Bradburry
Sent: Sunday=2C April 18=2C 2010 12:59 PM
Subject: AeroElectric-List: how to wire an electret microphone
I am considering trying to build a headphone for my plane. Can someone tel
l me how to wire an electret microphone like the one below so that it can b
e plugged into the planes jack?
http://www.radioshack.com/product/index.jsp?productId 62216
You can safely assume that I am dumb enough to try this with absolutely no
knowledge of how to do it and would need a very good explanation.
Something like=2C =93just use a condenser.=94=2C will not help me much=85
:>)
Bill B
href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.ma
tronics.com/Navigator?AeroElectric-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
________________________________________________________________________________
| From: | Bob Falstad <bobair(at)me.com> |
| Subject: | B & C Specialties Warning Light- Would Like to Dim |
I'm starting a significant upgrade of the VFR-only panel in my flying GlaStar to
an IFR panel. I currently have the B & C Specialty LR3C-14 alternator controller
and will be installing the B & C SD-20 standby alternator with a SB1B-14
controller. The currently installed low voltage light will be replaced with
a "standby alternator on" light.
The current warning light is way too bright, especially at night. I expect the
standby alternator "on" light to be just as bright.
Is there an easy way to dim the light after it has come on and gotten my attention?
If dimming it is too difficult, I'm thinking of adding a small switch so
I can shut it off after it has come on. This switch would be normally "on" and
I'd have to add that as a checklist item.
I already have and will continue to use a B & C dimmer (DIM5-14 or DIM15-14).
If I recall correctly, it will handle two or three different circuits. Can it
be wired such that it will dim the warning light while increasing the brightness
of the other circuit -- say my other panel lights -- or do all circuits have
to work in the same direction? If it can dim one circuit while brightening
up the other, I think I could find a happy medium and use existing hardware.
Bob
GlaStar
N248BF
~300 Hours
________________________________________________________________________________
| From: | Ron Quillin <rjquillin(at)cox.net> |
| Subject: | Re: how to wire an electret microphone |
At 19:34 4/18/2010, you wrote:
>The description says this is an "Electret Mic" but one of the
>reviews points out that in fact it is actually a "Condenser Mic". I
>don't know the significance of that discrepancy, but it is something
>you might want to note.
An electret mic is nothing more than internally polarized condenser
mic that only needs an external low voltage applied to make the
innards (amplifier) work. Most inexpensive ones are
omni-directional, and any response pattern is achieved in how it is
mounted and packaged.
Ron Q.
________________________________________________________________________________
| From: | "Keith Burris" <klburris(at)frontiernet.net> |
| Subject: | The Miracle Whip series antennas |
Folks;
>From the 'for what it's worth' dept --
I bought a plane that had a standard Comant antenna mounted on the bottom on
an almost all metal plane. Sitting on the ground, I was unable to receive
weather. I replaced that antenna with a miracle whip placed in a small
fiberglass portion of the plane at about the same distance from the ground.
I was amazed at the results in reception and also the cleanliness of
reception. Friends told me my radio coms were crystal clear. I am a happy
Miracle Whip user. The antenna is also in one piece, so if you dont glue it
in place, it will serve as a great rubber duck replacement for a handheld.
-- Keith
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | how to wire an electret microphone |
4/19/2010
Hello Ron Quillen, Thanks for your input.
You wrote: "Most inexpensive ones are omni-directional,......."
Yes, but some mics are not omni-directional and I don't know what bearing
cost has on that.
I learned that the hard way when I could not get one to work and fussed
around buying a new one and calling the manufacturer only to learn that all
I had to do was swap the leads to the mic to get it to work.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
==================================================
From: Ron Quillin <rjquillin(at)cox.net>
Subject: Re: AeroElectric-List: how to wire an electret microphone
At 19:34 4/18/2010, you wrote:
>The description says this is an "Electret Mic" but one of the
>reviews points out that in fact it is actually a "Condenser Mic". I
>don't know the significance of that discrepancy, but it is something
>you might want to note.
An electret mic is nothing more than internally polarized condenser
mic that only needs an external low voltage applied to make the
innards (amplifier) work. Most inexpensive ones are
omni-directional, and any response pattern is achieved in how it is
mounted and packaged.
Ron Q.
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Accurate Altitude and Airspeed |
4/19/2010
Hello Sam Hoskins, Thanks for your kind words.
You wrote: "I will definitely be investigating the wedges at the static
ports."
You will have lots of fun doing that. Attached are pictures of my two static
ports, one left and
one right on the forward sides of my KIS TR-1 fuselage.
One has a wedge on it the other one does not. I went through a long series
of trial and error alternately blocking off ports individually and wedging
them in various ways until I became satisfied with my airspeed indication in
the 70 KIAS arena.
The IAS may not be absolutely correct, but I know that when I fly a landing
approach at 75 KIAS and a touch of engine power above idle I should be able
to make a decent flare and touchdown (if the gods are smiling).
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
==============================================
Subject: Re: AeroElectric-List: Accurate Altitude and Airspeed
From: Sam Hoskins <sam.hoskins(at)gmail.com>
This is great information about the static ports. I recently switched from
steam gauges to a Dynon FlightDek. One of the neatest features is the winds
aloft display. Unfortunately, I figured out that it was pretty inaccurate.
One day, I went up and flew four headings and this is what got:
Compass Wind Direction Wind Speed
360 242 20
270 334 18
180 251 31
090 271 08
This told me the display was pretty much worthless. I posted s couple of
notes about it on the Dynon factory forum and was told to look after my
static ports, but no indication how to go about it.
I will definitely be investigating the wedges at the static ports.
Thanks.
Sam Hoskins
Murphysboro, IL
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Accurate Altitude and Airspeed |
4/19/2010
Hello Kevin Horton, You wrote: "The important aspect is the effect on the
altimeter accuracy."
Thank you for your most pertinent observation.
I wrote in my original post: "...but how do we know that the airspeed and
altitude information is inaccurate in the first place and during our trial
and error efforts how do we know when we have achieved the accuracy that we
are seeking? The answer to those two questions is not as
simple as one might first expect. I won't attempt to answer them here
because the answers are too big and complex to answer in this forum. What I
will suggest is that the reader google "accurate airspeed" and "accurate
altitude" and delve into those subjects to the level desired."
One of the web sites that I had specifically in mind when I wrote that was
your superb treatment of the subject at this web page created by you.
http://www.kilohotel.com/rv8/rvlinks/ssec.html
You most modestly did not mention it, but I would like to draw the reader's
attention to it and thank you for your efforts on our behalf.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
============================================================
Subject: Re: AeroElectric-List: Accurate Altitude and Airspeed
From: Kevin Horton <khorton01(at)rogers.com>
On 2010-04-15, at 18:06 , wrote:
> One thing that I've never quite understood regarding these methods is the
> focus on precisely determining airspeed accuracy indication in the
> cruising
> airspeed range. If I determine that my airspeed indicator shows 150 knots
> indicated airspeed and I determine through some elaborate scheme that I am
> actually only going 145 knots through the air what do I do with that
> information? Being 5 nautical miles short of my destination after a one
> hour
> flight is a trivial naviagation error contribution compared to all the
> other
> error sources (such as heading, wind, and climb airspeed) that I have to
> contend with and should overcome anyway by some means of real time
> enroute
> navigation.
>
> I think that if I were going to invest a lot of time and effort in
> determining my exact airspeed error I would be inclined to do that
> determination in the approach airspeed arena, not the cruising airspeed
> arena. And even then I would not be obsessed with absolute airspeed
> accuracy, I'd just want to know what number on the indicator gives me the
> right kind of safe approach and landing time after time.
As you note, an accurate airspeed indication is not really that important,
looked
at in isolation. Even if there is a significant error at approach speeds,
it is not so important as long as the error is the same on every flight.
Determining
what IAS our aircraft needs for a safe, effective approach and landing
is one of the many things we will do during the flight test phase.
But, with modern avionics, many EFIS systems calculate TAS based on IAS,
altitude
and temperature, and use that in conjunction with GPS track and groundspeed
to calculate wind. They then put a nice little wind vector on the display,
and
it bugs the heck out of folks if the wind info is wrong.
The most important aspect of static system errors is not the effect on IAS.
The
important aspect is the effect on the altimeter accuracy. It is quite
possible
to have static system position errors that will give over 100 ft error in
the altimeter at cruise airspeeds. If we are flying at our VFR cruising
altitude,
and there is IFR traffic that is supposed to be 500 ft above or below us,
errors in our static system can become significant. If we have 100 ft of
static
system error, plus each aircraft has 50 ft of altimeter instrument error,
plus perhaps we are not on quite the right altimeter setting because we
aren't
using flight following, and each pilot is 50 ft high or low from his nominal
indicated altitude, these errors may add up. It is quite conceivable that
aircraft
that are supposed to be 500 ft apart may turn out to be a have less than
200 ft of altitude separation. If we are flying IFR approaches in IMC, the
effect of static system position error on our altimeter is important to
know.
--
Kevin Horton
RV-8
Ottawa, Canada
http://www.kilohotel.com/rv8
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Designing a circuit question |
Good Morning 'Lectric Bob,
This discussion of controlling a circuit by noting the change in power
consumption has gotten me to think a bit and that is always dangerous.
My electrical knowledge is miniscule, but I can generally understand the
principles once they have been explained by you and the other good
instructors on this list.
I have the desire to know when fuel stops flowing from one tank to another
tank via an electric pump.
In other words, I would like to know when all of the fuel from a tank has
been transferred. My transfer system uses a Facet plunger style pump and
as the tank runs dry, the sound of the pump changes.
Unfortunately, I can only hear the pump running when I am parked on the
ground with my engine shut down. I have tried to monitor the total system
amperage load to see if I could detect the change when a tank runs dry, bu
t the
load seems to oscillate enough that I cannot pick it up via that
instrument. I am using an E.I. VA-1A to monitor the alternator output.
Is there a simple and, hopefully, economical way to measure the amount of
current it takes to drive the pump or is there a better way to tell when
fuel is no longer being transferred? I have thought of using a pressure
gauge
in the fuel line, but maybe it would be easier to measure the change in
current draw of the fuel pump?
Facet says that the pump can be run dry for a short period of time, but
they will not specify how long that time can be!
I hate to run my pump when it is operating dry. An indicator light to tell
me it is running dry would sure be helpful.
Any help available is sincerely appreciated.
Happy Skies,
Old Bob
Downers Grove, IL
Stearman N3977A
In a message dated 4/18/2010 2:14:46 P.M. Central Daylight Time,
nuckolls.bob(at)aeroelectric.com writes:
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
At 06:01 PM 4/17/2010, you wrote:
>I have an in flight adjustable IVO prop. What
>I=99d like to have is a light that indicates when
>I get to the flat pitch =98stop=99 =93 without adding
rings and brushes.
>For those who aren=99t familiar with the IVO, the
>adjustment is made by a motor driving a
>jack-screw that moves a collar which torques a
>rod embedded in the blades. There are no
>electrical stops, just a rubber washer at each
>end of the run. When the collar hits the end,
>the motor stalls. The rubber washer provides a
>softer stall which is a bit easier on the gears
>driving the jack screw. A 10A CB is the
>ultimate =98stop=99. Not elegant, but it works.
>On the ground, before starting the engine, it=99s
>easy to verify the prop is in fine pitch by
>listening to the motor. The problem is before
>landing, when I=99d like to have the prop in fine
>pitch, it has to be done by guess and feel, or
>just hold the switch until the CB pops =93 which
>is not a good thing to do on a regular basis.
>So, what I=99d like is a circuit that can sense an
>amperage spike =93 going over 9A would be perfect
>=93 and turn on a light (LED of course :-) The
>ramp up to 9A is steep =93 goes from 5-6A to 9A very quickly (if
that
helps).
>I can build the circuit, I just don=99t know how to design it.
The reed switch sensor Joe mentioned is worthy of further
thought. You could also build a simple constant current
generator set for something less than the CB trip current.
By watching for the voltage to spike across the generator
could light an LED to indicate end-of-travel and stop using
the CB as an operating indicator.
I'm just getting ready to head for Wichita but I'll noodle
the idea on the way up. I can perhaps publish something later
this evening.
Bob . . .
========================
===========
========================
===========
========================
===========
========================
===========
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: how to wire an electret microphone |
>
>However,... the first thing is to probably consider is the type of
>mike element. It has to deal with cancelling most of the back
>ground noise. I am guessing the RS mike element may not qualify as
>a noise cancelling mike....
Excellent point. Noise canceling microphones not only
have special microphone cartridges (openings on BOTH
side of diaphragm) the housing that mounts them is
also tailored to the task. The idea is that far field
stimulus (cabin noise) gets applied equally to both
sides of the diaphragm while near field stimulus
(voice) concentrates on one side.
Optimizing the noise cancelling qualities is not
a trivial task. In fact, some of big names in
aircraft headsets have stubbed their toes from
time to time.
The most effective microphones I've ever encountered
were the military headset dynamic devices (very low
impedance . . . . about 5 ohms as I recall) and
very small useful signal output but with stellar
noise cancelling characteristics. Their electrical
characteristics demanded some real talent for handling
micro-volt level signals of interest in an electrically
noisy environment.
These microphone signals were always processed in
the ship's intercom panel before being applied to
radio's as 1 volt rms signals.
The original carbon mics used general aviation
aircraft had HUGE output signals and not very
hot noise cancelling characteristics. They
were relatively cheap to build, rugged and
VERY easy to integrate into the electronics.
Then there's issues of wind noise. You didn't say
if your application was in a closed cabin or an
ultra-light style environment . . . but being
able to perform in the wind adds a whole new dimension
to the design task. The folks who do motorcycle
intercoms have done a pretty good job in the
low-cost systems markets.
I fiddled with them just enough about 30 years
ago to decide that it was a discipline that I
wasn't going to add to my bag of tricks. Poor
return on investment for the $time$ needed to
achieve useful results. Some of the best microphones
I've run across were on the least expensive
headsets. The last set I bought for the airport
were only about $150 as I recall . . . don't
remember the brand/model right now . . . but
they worked really well in our C-150's.
Bob . . .
________________________________________________________________________________
| From: | "Chris Hukill" <cjhukill(at)cox.net> |
| Subject: | transponder question |
I am currently planning my IFR panel for my RV10. Does anyone know what
the future requirements for ADSB transceivers will be and does it negate
the need for a mode C transponder. If that's the case what is the
timeframe for not needing a mode C and needing the UAT for the ADSB?
Chris Hukill
________________________________________________________________________________
| Subject: | Re: Designing a circuit question |
| From: | Dj Merrill <deej(at)deej.net> |
On 04/19/2010 07:39 AM, BobsV35B(at)aol.com wrote:
> I have the desire to know when fuel stops flowing from one tank to
> another tank via an electric pump.
How about an optical in-line fuel sensor?
http://www.pillarpointelectronics.com/ufstkit.html
<http://www.pillarpointelectronics.com/ufstkit.html>
-Dj
--
Dj Merrill - N1JOV
Glastar Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/
Grumman Yankee Driver N9870L - http://deej.net/yankee/
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Prop Pitch Controller |
I've sketched a current limiter circuit and posted it
at:
http://aeroelectric.com/Pictures/Schematics/PropPitchController.pdf
The parts are available from http://digikey.com and the bill of
materials is about $10.
Under normal operations, the big N-fet transistor is turned on
hard (under 3 milliohms). Combined wit the 0.1 ohm resistor
in series will contribute less than 1/2 volt drop to normal
motor operating voltage. Gate drive comes though the LED/2.2K
resistor string from +14v.
When the motor hits the stop and stalls, current will rise
to the point where the 2N3904 gets turned on by voltage drop
across the .1 ohm resistor. The transistor pulls down on a
2.2K resistor causing the LED to light up and simultaneously
starving the N-fet for gate drive. The circuit will limit
total current to some value on the order of 6A thus preventing
a trip of the circuit breaker.
The N-fet needs to be on a heat sink suited for up to say
5 seconds of delayed turn-off after the motor hits the
stop. This needn't be much. You could build this assembly
on say 6 sq inches of .062 or thicker aluminum. It might
have a right-angle bend along one edge for a mounting
flange. The fet needs to be isolated from the heatsink
with a suitable insulating washer.
During stall-time, the N-fet is dumping about 14v x 6a
or 80 watts of heat. Okay on small heat sink for a few
seconds. There is no protective feature that would prevent the
n-fet from getting smoked if someone holds the switch
too long while the motor is jammed against the stop. With
a few more components, we can probably add time delay
feature that deprives the n-fet of gate drive a few
seconds after the stop is reached. I suspect you won't
need it.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: B & C Specialties Warning Light- Would Like to |
Dim
At 09:30 PM 4/18/2010, you wrote:
>
>I'm starting a significant upgrade of the VFR-only panel in my
>flying GlaStar to an IFR panel. I currently have the B & C
>Specialty LR3C-14 alternator controller and will be installing the B
>& C SD-20 standby alternator with a SB1B-14 controller. The
>currently installed low voltage light will be replaced with a
>"standby alternator on" light.
>
>The current warning light is way too bright, especially at night. I
>expect the standby alternator "on" light to be just as bright.
When we did that design, the goal was to be sun-light viewable
in a canopy airplane (LongEz was king back then). I think Bill
was supplying 6v lamps in fixtures for extra intensity. Consider
putting a 24 volt lamp in the fixtures.
Also, consider this lamp fixture to replace the stock fixture.
http://aeroelectric.com/Pictures/Lighting/PTT_Dim_Fixture.jpg
They're scarce but not rare and a bit pricey new
but available surplus/salvage. These are mechanically
dimmed and were very common in aircraft panels of yesteryear.
They offer a drop-in, plug-n-play solution.
>Is there an easy way to dim the light after it has come on and
>gotten my attention? If dimming it is too difficult, I'm thinking
>of adding a small switch so I can shut it off after it has come
>on. This switch would be normally "on" and I'd have to add that as
>a checklist item.
I had some builders simply unscrew the lamp dome
along with it's bulb and stick it in their
pocket. It's the unusual flight condition that
would offer extended operations with the light
flashing.
>I already have and will continue to use a B & C dimmer (DIM5-14 or
>DIM15-14). If I recall correctly, it will handle two or three
>different circuits. Can it be wired such that it will dim the
>warning light while increasing the brightness of the other circuit
>-- say my other panel lights -- or do all circuits have to work in
>the same direction? If it can dim one circuit while brightening up
>the other, I think I could find a happy medium and use existing hardware.
You can tie the + supply for the warning lights
to you dimmed panel lamps . . . but you need to
use caution here. The panel lamps would need to
be running on high intensity for daytime viewability
of the warning lamps.
I think I'd go with mechanically dimmed fixture
or put-it-in-the-pocket. But check out the 24v
lamp option too.
Bob . . .
________________________________________________________________________________
| From: | David <ainut(at)knology.net> |
| Subject: | Re: RE: Designing a circuit question |
For simplicity's sake, look at the Arduino. For more detailed
information, start at Freescale's (formerly Motorola) sites.
David
Doug Ilg wrote:
> --> AeroElectric-List message posted by: Doug Ilg
>
> Dennis,
>
> I'm not really the right person to give lessons on microprocessors. All that
I've done is to implement simple schematics and programs that I found on the
'net. (A quick search for "PIC16" should find some sites with projects for that
popular line of microprocessors.) I know from that that you can drive an LED
directly off an output pin with an appropriate resistor.
>
> My point was to tell you that the relay that was referred to is not necessary
for your original purpose (to light an LED). It would be useful to actually
interrupt current to the motor, if you chose to do that.
>
> Maybe the person who originally suggested using a microprocessor can give you
better advice on how to use those.
>
> Doug Ilg
> Grumman Tiger N74818, College Park Airport (KCGS), Maryland
> Challenger II LSS LW (N641LG reserved) - kit underway at Laurel Suburban (W18)
>
>
> ----- Original Message ----
>
>> From: Dennis& Anne Glaeser<glaesers(at)wideopenwest.com>
>> To: aeroelectric-list(at)matronics.com
>> Sent: Sun, April 18, 2010 6:42:02 PM
>> Subject: AeroElectric-List: Re: RE: Designing a circuit question
>>
> Doug,
>
> It
>
>> may be clear to you, but you've got to do better than that to be clear to
>>
> me
>
>> :-)
>>
> I understand the concept, but need a circuit diagram, and which
>
>> $1
>>
> microprocessor to use.
> I agree that once I know how to turn the LED on,
>
>> adding a relay is straight
>>
> forward. Have to admit I hadn't thought of
>
>> that. I have to think about it
>>
> and decide if it is worth the extra
>
>> complexity and parts - vs. just me just
>>
> letting go of the
>
>> switch...
>>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Facet pumps: Energy vs. Flow |
Good Morning 'Lectric Bob,
This discussion of controlling a circuit by noting the change in
power consumption has gotten me to think a bit and that is always dangerous.
But exciting too! Fortunately much less hazardous than
inverted flight 6' off the runway . . .
My electrical knowledge is miniscule, but I can generally understand
the principles once they have been explained by you and the other
good instructors on this list.
I have the desire to know when fuel stops flowing from one tank to
another tank via an electric pump.
In other words, I would like to know when all of the fuel from a tank
has been transferred. My transfer system uses a Facet plunger style
pump and as the tank runs dry, the sound of the pump changes.
Unfortunately, I can only hear the pump running when I am parked on
the ground with my engine shut down. I have tried to monitor the
total system amperage load to see if I could detect the change when a
tank runs dry, but the load seems to oscillate enough that I cannot
pick it up via that instrument. I am using an E.I. VA-1A to monitor
the alternator output.
Is there a simple and, hopefully, economical way to measure the
amount of current it takes to drive the pump or is there a better way
to tell when fuel is no longer being transferred? I have thought of
using a pressure gauge in the fuel line, but maybe it would be easier
to measure the change in current draw of the fuel pump?
Facet says that the pump can be run dry for a short period of time,
but they will not specify how long that time can be!
I hate to run my pump when it is operating dry. An indicator light to
tell me it is running dry would sure be helpful.
Any help available is sincerely appreciated.
I've not studied the Facet pumps but waaayyyy back
when, the Bendix thump-thump pumps were king. Those
pumps used a solenoid to "cock" a spring that in
turn put pressure on the fuel. Selecting a spring
tension sets the fuel pump's output pressure. When
the plunger bottoms out, contacts close to energize
the solenoid thus re-cocking the spring for the
next stroke.
Obviously, the current draw of this device is
constant . . . it's a function of applied voltage
and coil resistance of the solenoid. So if we're
to remain faithful to the laws of conservation of
energy, then the thing that changes for pump
load is FREQUENCY. The lower the back pressure,
the faster the pump cycles for each stroke. Maximum
frequency occurs when the back pressure went to zero.
Do the Facets do the same thing? I've had a pump
laying here for several years. Somebody sent me one
to do an energy study at various pressures and
flows for a load analysis . . . never got around
to setting it up. Probably ought to do that.
It would be cool if we could get the Facet patent
numbers to look up their operating principals.
Bob . . .
________________________________________________________________________________
| Subject: | Re: B & C Specialties Warning Light- Would Like to |
Dim
| From: | "user9253" <fran4sew(at)banyanol.com> |
Here is a circuit to dim a lamp.
http://public.bay.livefilestore.com/y1pVqq2FYLLgCKpbuePN3hR2wkiWR6Df_p9F5fNZVjfBbIR6CPx-VYQ7Zo3Qj3z-2-t2qc_8BmTDQ_SzdazZkFHRQ/Lamp%20dimmer.jpg
The lamp will illuminate normally until the momentary switch is pushed. The relay
will then pull in and hold until the alarm condition no longer exists. With
the relay energized, full voltage is removed from the lamp and is replaced
by reduced voltage through the resistor and D2. If it is desired that the lamp
go out completely, leave the resistor and diode out of the circuit.
Joe[/list]
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294837#294837
Attachments:
http://forums.matronics.com//files/lamppercent20dimmer1_832.jpg
________________________________________________________________________________
| Subject: | Re: B & C Specialties Warning Light- Would Like to |
Dim
| From: | "user9253" <fran4sew(at)banyanol.com> |
bobair,
Here is a circuit to dim a lamp.
http://public.bay.livefilestore.com/y1pnjhA-QOagoszIUOS_iGTx6Uw9gnQ1G-xEr5gCUrpDQ4RGg9zXqzo-0gwBpbT2GBxlz9tWj7Y1QjbnTMtbIq4Sw/Lamp%20dimmer.jpg
The lamp will illuminate normally until the momentary switch is pushed. Then the
relay will energize and hold until the alarm condition goes away. With the
relay energized, the lamp current is reduced by the resistor. If it is desired
that the lamp go out completely, remove the resistor from the circuit.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294843#294843
Attachments:
http://forums.matronics.com//files/lamp_dimmer_397.jpg
________________________________________________________________________________
| From: | Sean Stephens <sean(at)stephensville.com> |
| Subject: | Re: RE: Designing a circuit question |
I've also had fun playing around with this to help learn the basics.
http://www.nerdkits.com/
On 4/19/10 9:32 AM, David wrote:
>
> For simplicity's sake, look at the Arduino. For more detailed
> information, start at Freescale's (formerly Motorola) sites.
>
> David
>
>
> Doug Ilg wrote:
>> --> AeroElectric-List message posted by: Doug Ilg
>>
>> Dennis,
>>
>> I'm not really the right person to give lessons on microprocessors.
>> All that I've done is to implement simple schematics and programs
>> that I found on the 'net. (A quick search for "PIC16" should find
>> some sites with projects for that popular line of microprocessors.)
>> I know from that that you can drive an LED directly off an output pin
>> with an appropriate resistor.
>>
>> My point was to tell you that the relay that was referred to is not
>> necessary for your original purpose (to light an LED). It would be
>> useful to actually interrupt current to the motor, if you chose to do
>> that.
>>
>> Maybe the person who originally suggested using a microprocessor can
>> give you better advice on how to use those.
>>
>> Doug Ilg
>> Grumman Tiger N74818, College Park Airport (KCGS), Maryland
>> Challenger II LSS LW (N641LG reserved) - kit underway at Laurel
>> Suburban (W18)
>>
>>
>>
>> ----- Original Message ----
>>> From: Dennis& Anne Glaeser<glaesers(at)wideopenwest.com>
>>> To: aeroelectric-list(at)matronics.com
>>> Sent: Sun, April 18, 2010 6:42:02 PM
>>> Subject: AeroElectric-List: Re: RE: Designing a circuit question
>> Doug,
>>
>> It
>>> may be clear to you, but you've got to do better than that to be
>>> clear to
>> me
>>> :-)
>> I understand the concept, but need a circuit diagram, and which
>>> $1
>> microprocessor to use.
>> I agree that once I know how to turn the LED on,
>>> adding a relay is straight
>> forward. Have to admit I hadn't thought of
>>> that. I have to think about it
>> and decide if it is worth the extra
>>> complexity and parts - vs. just me just
>> letting go of the
>>> switch...
>>
>>
>>
>>
>>
>>
>>
>
>
________________________________________________________________________________
| Subject: | Re: Prop Pitch Controller |
| From: | Etienne Phillips <etienne.phillips(at)gmail.com> |
On 19 Apr 2010, at 4:50 PM, Robert L. Nuckolls, III wrote:
>
> I've sketched a current limiter circuit and posted it
> at:
>
> http://aeroelectric.com/Pictures/Schematics/PropPitchController.pdf
>
> The parts are available from http://digikey.com and the bill of
> materials is about $10.
Hi Bob, and everyone else following this thread...
I have an even simpler solution, possibly costing significantly less, using the
hotly debated poly-fuse. Simply put a 6A or 7A one in series with the motor,
with an LED+resistor across it. When the fuse trips, the LED is energised... In
it's normal state, all the current travels through the low impedance fuse, and
'none' through the LED+resistor path. No heatsink required! However, there
is the problem of securing everything and making sure vibration doesn't age the
soldered joints prematurely.
Comments?
Thanks
Etienne
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Good Afternoon 'Lectric Bob,
To me, they look and sound just like the ones that were used on those Ford
gasoline fired heaters back in the thirties. But my memory could be fooling
me.
Those were probably the Stewart Warner or Bendix pumps. Whadda Ya Think?
If so. does that mean I need to monitor the frequency some how?
This is getting complicated,. No wonder nobody does it!
Happy Skies,
Old Bob
In a message dated 4/19/2010 10:17:33 A.M. Central Daylight Time,
nuckolls.bob(at)aeroelectric.com writes:
Good Morning 'Lectric Bob,
This discussion of controlling a circuit by noting the change in power
consumption has gotten me to think a bit and that is always dangerous.
But exciting too! Fortunately much less hazardous than
inverted flight 6' off the runway . . .
My electrical knowledge is miniscule, but I can generally understand the
principles once they have been explained by you and the other good
instructors on this list.
I have the desire to know when fuel stops flowing from one tank to another
tank via an electric pump.
In other words, I would like to know when all of the fuel from a tank has
been transferred. My transfer system uses a Facet plunger style pump and
as the tank runs dry, the sound of the pump changes.
Unfortunately, I can only hear the pump running when I am parked on the
ground with my engine shut down. I have tried to monitor the total system
amperage load to see if I could detect the change when a tank runs dry, but
the load seems to oscillate enough that I cannot pick it up via that
instrument. I am using an E.I. VA-1A to monitor the alternator output.
Is there a simple and, hopefully, economical way to measure the amount of
current it takes to drive the pump or is there a better way to tell when
fuel is no longer being transferred? I have thought of using a pressure gauge
in the fuel line, but maybe it would be easier to measure the change in
current draw of the fuel pump?
Facet says that the pump can be run dry for a short period of time, but
they will not specify how long that time can be!
I hate to run my pump when it is operating dry. An indicator light to tell
me it is running dry would sure be helpful.
Any help available is sincerely appreciated.
I've not studied the Facet pumps but waaayyyy back
when, the Bendix thump-thump pumps were king. Those
pumps used a solenoid to "cock" a spring that in
turn put pressure on the fuel. Selecting a spring
tension sets the fuel pump's output pressure. When
the plunger bottoms out, contacts close to energize
the solenoid thus re-cocking the spring for the
next stroke.
Obviously, the current draw of this device is
constant . . . it's a function of applied voltage
and coil resistance of the solenoid. So if we're
to remain faithful to the laws of conservation of
energy, then the thing that changes for pump
load is FREQUENCY. The lower the back pressure,
the faster the pump cycles for each stroke. Maximum
frequency occurs when the back pressure went to zero.
Do the Facets do the same thing? I've had a pump
laying here for several years. Somebody sent me one
to do an energy study at various pressures and
flows for a load analysis . . . never got around
to setting it up. Probably ought to do that.
It would be cool if we could get the Facet patent
numbers to look up their operating principals.
Bob . . .
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Designing a circuit question |
Good Afternoon Dj,
That sounds like just what I need!
Unfortunately, I want to use it on a certificated airplane. I will check
it out.
Thanks much for the information.
Happy Skies,
Old Bob
In a message dated 4/19/2010 9:48:46 A.M. Central Daylight Time,
deej(at)deej.net writes:
--> AeroElectric-List message posted by: Dj Merrill
On 04/19/2010 07:39 AM, BobsV35B(at)aol.com wrote:
> I have the desire to know when fuel stops flowing from one tank to
> another tank via an electric pump.
How about an optical in-line fuel sensor?
http://www.pillarpointelectronics.com/ufstkit.html
<http://www.pillarpointelectronics.com/ufstkit.html>
-Dj
--
Dj Merrill - N1JOV
Glastar Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/
Grumman Yankee Driver N9870L - http://deej.net/yankee/
________________________________________________________________________________
| Subject: | Re: Designing a circuit question |
| From: | "user9253" <fran4sew(at)banyanol.com> |
I wrapped 25 turns of 20awg magnet wire around a magnetic reed switch. I was surprised
at how well it works. Less than 1/2 amp is enough to close the switch.
Very few turns of wire will be required for Dennis' application of turning
on a light when motor current exceeds 7amps.
Joe
Ref: http://www.aeroelectric.com/articles/Failure_Detection_and_Annunciation.pdf
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294867#294867
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
| Subject: | Facet pumps: Energy vs. Flow |
To me, they look and sound just like the ones that were used
on those Ford gasoline fired heaters back in the thirties. But my memory
could be fooling me.
Those were probably the Stewart Warner or Bendix pumps.
Whadda Ya Think?
If so. does that mean I need to monitor the frequency some
how?
This is getting complicated,. No wonder nobody does it!
Happy Skies,
Old Bob
I am not sure of the application here, but I
believe that there should be a significant pressure drop on the output of
the pump, when there is no longer any fuel. This being the case, perhaps
you could use a pressure switch, similar to what is used to monitor engine
oil pressure and turn on the hobbs meter, on some aircraft. You would need
to check the pressure differential between pumping fuel and empty tank
pumping, and use a switch midway between. This would be a normally closed
switch which would open when there is fuel flow and close, to turn on the
light when there is no more fuel to pump.
Not sure if this is a viable option for your
application, but might work, and is very simple. (I especially like
simple:-)
Roger
________________________________________________________________________________
| From: | "Glaeser, Dennis" <dennis.glaeser(at)hp.com> |
| Subject: | Re: Prop Pitch Controller |
Thanks Bob!
Now a few questions:
Does the current limiting characteristic you mention literally limit the current
to the pitch motor? My guess is it does (at least somewhat), which is why the
N-fet becomes a cabin heater.
I'm thinking that the electrical paths from the switch to the N-fet, and path from
the N-fet to the ALSRJ resistor to ground need to be capable of 10A, but the
other wiring will see much less.
How would I 'adjust for desired limit' on the ALSRJ resistor to go up to say 8A?
How did you calculate or estimate that value? How sensitive would you anticipate
that to be?
The reason I ask is that the load on the motor does increase as the pitch on the
blades approach the high (and low) pitch limits, before the mechanical stop
is reached. The mechanism is literally twisting composite blades, they don't rotate
in bearings like 'regular' adjustable blades. I may have to adjust the current
limit to be sure I can get the blades close enough to the pitch limits
for my purposes. My rough measurement of current (reading a clamp on meter) indicates
a pretty good knee in the curve at around 8A. 6A may be close enough,
only testing will tell.
Finally, how would you compare this circuit to the reed switch approach that Joe
Gores proposed, from a standpoint of repeatability of sensing the target amperage,
and the ability to make adjustments to get to the desired target (number
of winds and wire size selection)?
As usual, I'm awed by, and grateful for, your generosity of time and talent.
Dennis
-------------------------------------------------------------------
From: Robert L. Nuckolls, III (nuckolls.bob(at)aeroelectric.com)
Date: Mon Apr 19 - 7:52 AM
I've sketched a current limiter circuit and posted it
at:
http://aeroelectric.com/Pictures/Schematics/PropPitchController.pdf
________________________________________________________________________________
| Subject: | Bussmann fuse blocks |
Jef,
I've got a 6 & 12 position (mounted once but never used) you can have for postage
from 19038 in the US.
Glenn
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of James Kilford
Sent: Friday, April 16, 2010 1:26 PM
Subject: Re: AeroElectric-List: Bussmann fuse blocks
Jef,
I ordered mine from B&C Specialty. Got here in no time (to the UK).
http://www.bandc.biz/circuit-protective-devices.aspx
James
On Fri, Apr 16, 2010 at 4:26 PM, Jef Vervoort wrote:
> Bob and all,
>
>
> Im interested in using the Bussman fuse block, as suggested in Appendix Z
> Note 19.
>
>
> Where could I find these?
>
>
> Jef in Belgium, 91031.
>
>
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Good Afternoon Roger,
That is the path I was exploring before I read the idea of using the amount
of current needed to monitor a circuit. Just thought the electrical
solution might be simpler than using pressure. So far, I have not found a source
for pressure switches that will activate at the very low pressures
involved. I don't have exact numbers as yet, but it seems we will need to be
able to tell the difference between one PSI and about two PSI.
So far, that optical device seems the best, but I want to use this on a
certificated aircraft. Consequently, a pressure switch or anything else that
is put in the fuel system probably has to meet certification standards.
Just measuring the current could be considered as a Part 43 acceptable monitor.
Happy Skies,
Old Bob
In a message dated 4/19/2010 3:09:52 P.M. Central Daylight Time,
mrspudandcompany(at)verizon.net writes:
To me, they look and sound just like the ones that were used
on those Ford gasoline fired heaters back in the thirties. But my memory
could be fooling me.
Those were probably the Stewart Warner or Bendix pumps.
Whadda Ya Think?
If so. does that mean I need to monitor the frequency some
how?
This is getting complicated,. No wonder nobody does it!
Happy Skies,
Old Bob
I am not sure of the application here, but I
believe that there should be a significant pressure drop on the output of
the pump, when there is no longer any fuel. This being the case, perhaps
you could use a pressure switch, similar to what is used to monitor engine
oil pressure and turn on the hobbs meter, on some aircraft. You would need
to check the pressure differential between pumping fuel and empty tank
pumping, and use a switch midway between. This would be a normally closed
switch which would open when there is fuel flow and close, to turn on the
light when there is no more fuel to pump.
Not sure if this is a viable option for your
application, but might work, and is very simple. (I especially like
simple:-)
Roger
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Facet pumps: Energy vs. Flow |
On 4/19/2010 3:03 PM, ROGER & JEAN CURTIS wrote:
>
> To me, they look and sound just like the ones that were used
> on those Ford gasoline fired heaters back in the thirties. But my memory
> could be fooling me.
>
> Those were probably the Stewart Warner or Bendix pumps.
> Whadda Ya Think?
>
> If so. does that mean I need to monitor the frequency some
> how?
>
> This is getting complicated,. No wonder nobody does it!
>
> Happy Skies,
>
> Old Bob
>
> I am not sure of the application here, but I
> believe that there should be a significant pressure drop on the output of
> the pump, when there is no longer any fuel. This being the case, perhaps
> you could use a pressure switch, similar to what is used to monitor engine
> oil pressure and turn on the hobbs meter, on some aircraft. You would need
> to check the pressure differential between pumping fuel and empty tank
> pumping, and use a switch midway between. This would be a normally closed
> switch which would open when there is fuel flow and close, to turn on the
> light when there is no more fuel to pump.
>
> Not sure if this is a viable option for your
> application, but might work, and is very simple. (I especially like
> simple:-)
>
> Roger
>
If you're using it as a transfer pump, there won't be a lot of pressure
since it will be just the 'head' from one tank to the other. Often no
more than a few inches of rise, plus the resistance of the tubing.
How about one of the sensing devices using light to detect the presence
of liquid? I bought a couple several years ago, intending to use them to
monitor end-of-transfer from my aux tanks, then forgot to install
them.... They mount in a single hole & have a cone shaped plexi tip. An
LED shines out through the plexi; presence/absence of liquid changes the
light reflected back into the photocell in the same housing, changing
the state of the sense line.
If that interests you, I'll try to locate the name of the device & a
source for you.
Charlie
________________________________________________________________________________
| Subject: | Re: The Miracle Whip series antennas |
What is a Miracle Whip antenna?
Michael Wynn
RV 8 Finishing
San Ramon, CA
In a message dated 4/19/2010 12:47:59 A.M. Pacific Daylight Time,
klburris(at)frontiernet.net writes:
Folks;
>From the 'for what it's worth' dept --
I bought a plane that had a standard Comant antenna mounted on the bottom
on an almost all metal plane. Sitting on the ground, I was unable to
receive weather. I replaced that antenna with a miracle whip placed in a
small
fiberglass portion of the plane at about the same distance from the groun
d. I
was amazed at the results in reception and also the cleanliness of
reception. Friends told me my radio coms were crystal clear. I am a happy
Miracle
Whip user. The antenna is also in one piece, so if you don=99t glue
it in
place, it will serve as a great rubber duck replacement for a handheld.
-- Keith
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: B & C Specialties Warning Light- Would Like |
to Dim
At 10:16 AM 4/19/2010, you wrote:
>
>Here is a circuit to dim a lamp.
>http://public.bay.livefilestore.com/y1pVqq2FYLLgCKpbuePN3hR2wkiWR6Df_p9F5fNZVjfBbIR6CPx-VYQ7Zo3Qj3z-2-t2qc_8BmTDQ_SzdazZkFHRQ/Lamp%20dimmer.jpg
>The lamp will illuminate normally until the momentary switch is
>pushed. The relay will then pull in and hold until the alarm
>condition no longer exists. With the relay energized, full voltage
>is removed from the lamp and is replaced by reduced voltage through
>the resistor and D2. If it is desired that the lamp go out
>completely, leave the resistor and diode out of the circuit.
The B&C warning lamps flash and would not allow
the relay to remain latched.
Bob . . .
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Good Morning Charlie,
Those units by Pillar Point Electronics look very promising. As I said a
couple of messages back, I need something that can be used on a normally
certificated aircraft. Not sure about the PPE product, but I am checking into
it.
Thanks for the comment.
Happy Skies,
Old Bob
In a message dated 4/19/2010 4:50:49 P.M. Central Daylight Time,
ceengland(at)bellsouth.net writes:
--> AeroElectric-List message posted by: Charlie England
On 4/19/2010 3:03 PM, ROGER & JEAN CURTIS wrote:
>
> To me, they look and sound just like the ones that were used
> on those Ford gasoline fired heaters back in the thirties. But my memory
> could be fooling me.
>
> Those were probably the Stewart Warner or Bendix pumps.
> Whadda Ya Think?
>
> If so. does that mean I need to monitor the frequency some
> how?
>
> This is getting complicated,. No wonder nobody does it!
>
> Happy Skies,
>
> Old Bob
>
> I am not sure of the application here, but I
> believe that there should be a significant pressure drop on the output of
> the pump, when there is no longer any fuel. This being the case, perhaps
> you could use a pressure switch, similar to what is used to monitor
engine
> oil pressure and turn on the hobbs meter, on some aircraft. You would
need
> to check the pressure differential between pumping fuel and empty tank
> pumping, and use a switch midway between. This would be a normally
closed
> switch which would open when there is fuel flow and close, to turn on the
> light when there is no more fuel to pump.
>
> Not sure if this is a viable option for your
> application, but might work, and is very simple. (I especially like
> simple:-)
>
> Roger
>
If you're using it as a transfer pump, there won't be a lot of pressure
since it will be just the 'head' from one tank to the other. Often no
more than a few inches of rise, plus the resistance of the tubing.
How about one of the sensing devices using light to detect the presence
of liquid? I bought a couple several years ago, intending to use them to
monitor end-of-transfer from my aux tanks, then forgot to install
them.... They mount in a single hole & have a cone shaped plexi tip. An
LED shines out through the plexi; presence/absence of liquid changes the
light reflected back into the photocell in the same housing, changing
the state of the sense line.
If that interests you, I'll try to locate the name of the device & a
source for you.
Charlie
________________________________________________________________________________
| From: | Steve Thomas <lists(at)stevet.net> |
| Subject: | Re: The Miracle Whip series antennas |
http://www.miracleantenna.com/AirWhip.htm
Steve Thomas
________________________________________________________________________
On Apr 19, 2010, at 3:28 PM, MLWynn(at)aol.com wrote:
> What is a Miracle Whip antenna?
>
> Michael Wynn
> RV 8 Finishing
> San Ramon, CA
>
> In a message dated 4/19/2010 12:47:59 A.M. Pacific Daylight Time,
klburris(at)frontiernet.net writes:
>
> Folks;
>
> =46rom the 'for what it's worth' dept --
>
> I bought a plane that had a standard Comant antenna mounted on the
bottom on an almost all metal plane. Sitting on the ground, I was unable
to receive weather. I replaced that antenna with a miracle whip placed
in a small fiberglass portion of the plane at about the same distance
from the ground. I was amazed at the results in reception and also the
cleanliness of reception. Friends told me my radio coms were crystal
clear. I am a happy Miracle Whip user. The antenna is also in one piece,
so if you don=92t glue it in place, it will serve as a great rubber duck
replacement for a handheld.
>
>
>
>
>
> -- Keith
>
>
________________________________________________________________________________
| From: | paul wilson <pwmac(at)sisna.com> |
| Subject: | Battery chargers. |
Read this link an tell me your comments. News to me.
http://www.optimabatteries.com/product_support/resuscitating_agmbattery.php
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Certificated. Bummer.
If you think you can legally use current sensing, have you tried a
restricter in the pump's output to see if it will raise the current
enough to be measurable vs the no-flow state?
On 4/19/2010 6:16 PM, BobsV35B(at)aol.com wrote:
> Good Morning Charlie,
> Those units by Pillar Point Electronics look very promising. As I said
> a couple of messages back, I need something that can be used on a
> normally certificated aircraft. Not sure about the PPE product, but I
> am checking into it.
> Thanks for the comment.
> Happy Skies,
> Old Bob
> In a message dated 4/19/2010 4:50:49 P.M. Central Daylight Time,
> ceengland(at)bellsouth.net writes:
>
>
>
> On 4/19/2010 3:03 PM, ROGER & JEAN CURTIS wrote:
> >
> > To me, they look and sound just like the ones that were used
> > on those Ford gasoline fired heaters back in the thirties. But
> my memory
> > could be fooling me.
> >
> > Those were probably the Stewart Warner or Bendix pumps.
> > Whadda Ya Think?
> >
> > If so. does that mean I need to monitor the frequency some
> > how?
> >
> > This is getting complicated,. No wonder nobody does it!
> >
> > Happy Skies,
> >
> > Old Bob
> >
> > I am not sure of the application here, but I
> > believe that there should be a significant pressure drop on the
> output of
> > the pump, when there is no longer any fuel. This being the
> case, perhaps
> > you could use a pressure switch, similar to what is used to
> monitor engine
> > oil pressure and turn on the hobbs meter, on some aircraft. You
> would need
> > to check the pressure differential between pumping fuel and
> empty tank
> > pumping, and use a switch midway between. This would be a
> normally closed
> > switch which would open when there is fuel flow and close, to
> turn on the
> > light when there is no more fuel to pump.
> >
> > Not sure if this is a viable option for your
> > application, but might work, and is very simple. (I especially like
> > simple:-)
> >
> > Roger
> >
> If you're using it as a transfer pump, there won't be a lot of
> pressure
> since it will be just the 'head' from one tank to the other. Often no
> more than a few inches of rise, plus the resistance of the tubing.
>
> How about one of the sensing devices using light to detect the
> presence
> of liquid? I bought a couple several years ago, intending to use
> them to
> monitor end-of-transfer from my aux tanks, then forgot to install
> them.... They mount in a single hole & have a cone shaped plexi
> tip. An
> LED shines out through the plexi; presence/absence of liquid
> changes the
> light reflected back into the photocell in the same housing, changing
> the state of the sense line.
>
> If that interests you, I'll try to locate the name of the device & a
> source for you.
>
> Charlie
>
> *
>
>
> *
________________________________________________________________________________
| From: | Eric Schlanser <eschlanser(at)yahoo.com> |
| Subject: | switch breaker on ALT field |
While in the-design stage-of an electrical system for an OBAM homebuilt
done according to Z-13/8 and Z-24, I have searched the archives and have o
nly managed to-find a partial answer.--So I will ask directly of Bob
and the group. Is there any reason that the-panel circuit breakers-alon
gside the ALT-switches cannot be combined into two-combination switch/C
B's,-(assuming I can find reliable devices)?
-
Thanks in advance,
Eric Schlanser, W-10 with Lycoming and-Denso IR main ALT with B&C SD-8 au
x ALT=0A=0A=0A
________________________________________________________________________________
| Subject: | Re: Facet pumps: Energy vs. Flow |
| From: | Bill Boyd <sportav8r(at)gmail.com> |
How about some filtering on the "input" line of the ammeter? If we're
looking at constant-amplitude square wave current pulses of varying
frequency, a capacitive filter to perform an "integral" function might give
you an average-current-over-time measurement that closely matches the
frequency and therefore the load on the pump. In practice, I am not sure
from listening to my Facet pump all these years how much the frequency
changes as a function of load. There is a sound change as it self-primes
when I first hit it before engine-start.
Just a thought. I had to do the pneumatic equivalent (expansion chamber
plus input restrictor) to keep my manifold pressure digital readout from
jumping all around in an un-readable fashion. A little RC pi or L network
might do what you need.
Bill B.
On Mon, Apr 19, 2010 at 9:56 PM, Charlie England wrote:
> ceengland(at)bellsouth.net>
>
> Certificated. Bummer.
>
> If you think you can legally use current sensing, have you tried a
> restricter in the pump's output to see if it will raise the current enough
> to be measurable vs the no-flow state?
>
> On 4/19/2010 6:16 PM, BobsV35B(at)aol.com wrote:
>
>> Good Morning Charlie,
>> Those units by Pillar Point Electronics look very promising. As I said a
>> couple of messages back, I need something that can be used on a normally
>> certificated aircraft. Not sure about the PPE product, but I am checking
>> into it.
>> Thanks for the comment.
>> Happy Skies,
>> Old Bob
>> In a message dated 4/19/2010 4:50:49 P.M. Central Daylight Time,
>> ceengland(at)bellsouth.net writes:
>>
>>
>>
>> On 4/19/2010 3:03 PM, ROGER & JEAN CURTIS wrote:
>> >
>> > To me, they look and sound just like the ones that were used
>> > on those Ford gasoline fired heaters back in the thirties. But
>> my memory
>> > could be fooling me.
>> >
>> > Those were probably the Stewart Warner or Bendix pumps.
>> > Whadda Ya Think?
>> >
>> > If so. does that mean I need to monitor the frequency some
>> > how?
>> >
>> > This is getting complicated,. No wonder nobody does it!
>> >
>> > Happy Skies,
>> >
>> > Old Bob
>> >
>> > I am not sure of the application here, but I
>> > believe that there should be a significant pressure drop on the
>> output of
>> > the pump, when there is no longer any fuel. This being the
>> case, perhaps
>> > you could use a pressure switch, similar to what is used to
>> monitor engine
>> > oil pressure and turn on the hobbs meter, on some aircraft. You
>> would need
>> > to check the pressure differential between pumping fuel and
>> empty tank
>> > pumping, and use a switch midway between. This would be a
>> normally closed
>> > switch which would open when there is fuel flow and close, to
>> turn on the
>> > light when there is no more fuel to pump.
>> >
>> > Not sure if this is a viable option for your
>> > application, but might work, and is very simple. (I especially like
>> > simple:-)
>> >
>> > Roger
>> >
>> If you're using it as a transfer pump, there won't be a lot of
>> pressure
>> since it will be just the 'head' from one tank to the other. Often no
>> more than a few inches of rise, plus the resistance of the tubing.
>>
>> How about one of the sensing devices using light to detect the
>> presence
>> of liquid? I bought a couple several years ago, intending to use
>> them to
>> monitor end-of-transfer from my aux tanks, then forgot to install
>> them.... They mount in a single hole & have a cone shaped plexi
>> tip. An
>> LED shines out through the plexi; presence/absence of liquid
>> changes the
>> light reflected back into the photocell in the same housing, changing
>> the state of the sense line.
>>
>> If that interests you, I'll try to locate the name of the device & a
>> source for you.
>>
>> Charlie
>>
>> *
>>
>>
>> *
>>
>
>
________________________________________________________________________________
| Subject: | Re: Facet pumps: Energy vs. Flow |
| From: | "rampil" <ira.rampil(at)gmail.com> |
Good engineering principles favor measuring the actual parameter
you want, rather than a surrogate, especially when there is no
reliable one-to-one mapping of one to the other.
In the case of current draw, for example, overheating the coil or dirt
in the mechanism will probably change the current draw
Pressure downstream would depend on where the fill hose enters the
downstream tank, if at the bottom, or at a positive hydrostatic head, the
pressure downstream of the pump will stay positive while there is fuel
in the tank.
What about measuring fuel level in the feeding tank, is not that what you
really want to make a decision with? When it reads zero, stop pumping?
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=294942#294942
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Good Morning Bill,
Wow!
It appears that any suitable current measuring device will be a lot more
complex than my feeble brain can comprehend.
Thanks to you and all the others that have contributed to my on going
education.
In any case, it does seem that a few breadboard experiments are in order.
Happy Skies,
Old Bob
In a message dated 4/20/2010 6:41:53 A.M. Central Daylight Time,
sportav8r(at)gmail.com writes:
How about some filtering on the "input" line of the ammeter? If we're
looking at constant-amplitude square wave current pulses of varying frequency,
a capacitive filter to perform an "integral" function might give you an
average-current-over-time measurement that closely matches the frequency and
therefore the load on the pump. In practice, I am not sure from listening
to my Facet pump all these years how much the frequency changes as a
function of load. There is a sound change as it self-primes when I first hit
it
before engine-start.
Just a thought. I had to do the pneumatic equivalent (expansion chamber
plus input restrictor) to keep my manifold pressure digital readout from
jumping all around in an un-readable fashion. A little RC pi or L network
might do what you need.
Bill B.
On Mon, Apr 19, 2010 at 9:56 PM, Charlie England <_ceengland(at)bellsouth.net_
(mailto:ceengland(at)bellsouth.net) > wrote:
<_ceengland(at)bellsouth.net_ (mailto:ceengland(at)bellsouth.net) >
Certificated. Bummer.
If you think you can legally use current sensing, have you tried a
restricter in the pump's output to see if it will raise the current enough to
be
measurable vs the no-flow state?
On 4/19/2010 6:16 PM, _BobsV35B(at)aol.com_ (mailto:BobsV35B(at)aol.com) wrote:
Good Morning Charlie,
Those units by Pillar Point Electronics look very promising. As I said a
couple of messages back, I need something that can be used on a normally
certificated aircraft. Not sure about the PPE product, but I am checking into
it.
Thanks for the comment.
Happy Skies,
Old Bob
In a message dated 4/19/2010 4:50:49 P.M. Central Daylight Time,
_ceengland(at)bellsouth.net_ (mailto:ceengland(at)bellsouth.net) writes:
<_ceengland(at)bellsouth.net_ (mailto:ceengland(at)bellsouth.net) >
On 4/19/2010 3:03 PM, ROGER & JEAN CURTIS wrote:
>
> To me, they look and sound just like the ones that were used
> on those Ford gasoline fired heaters back in the thirties. But
my memory
> could be fooling me.
>
> Those were probably the Stewart Warner or Bendix pumps.
> Whadda Ya Think?
>
> If so. does that mean I need to monitor the frequency some
> how?
>
> This is getting complicated,. No wonder nobody does it!
>
> Happy Skies,
>
> Old Bob
>
> I am not sure of the application here, but I
> believe that there should be a significant pressure drop on the
output of
> the pump, when there is no longer any fuel. This being the
case, perhaps
> you could use a pressure switch, similar to what is used to
monitor engine
> oil pressure and turn on the hobbs meter, on some aircraft. You
would need
> to check the pressure differential between pumping fuel and
empty tank
> pumping, and use a switch midway between. This would be a
normally closed
> switch which would open when there is fuel flow and close, to
turn on the
> light when there is no more fuel to pump.
>
> Not sure if this is a viable option for your
> application, but might work, and is very simple. (I especially like
> simple:-)
>
> Roger
>
If you're using it as a transfer pump, there won't be a lot of
pressure
since it will be just the 'head' from one tank to the other. Often no
more than a few inches of rise, plus the resistance of the tubing.
How about one of the sensing devices using light to detect the
presence
of liquid? I bought a couple several years ago, intending to use
them to
monitor end-of-transfer from my aux tanks, then forgot to install
them.... They mount in a single hole & have a cone shaped plexi
tip. An
LED shines out through the plexi; presence/absence of liquid
changes the
light reflected back into the photocell in the same housing, changing
the state of the sense line.
If that interests you, I'll try to locate the name of the device & a
source for you.
Charlie
________________________________________________________________________________
| Subject: | Re: Facet pumps: Energy vs. Flow |
| From: | "Jon Finley" <jon(at)finleyweb.net> |
=0AI find this discussion very interesting and hope for an inexpensive solu
tion. I really like that Pillar Point flow detector but the price is more
than I'd like to spend.=0A =0AJust to add some data points.... In my case,
I know the fuel level in the tank but I wish to know when fuel stops being
delivered to that tank so alternate plans can be made. So, a "fuel is not f
lowing" indicator would add a level of comfort (would be "nice" but certain
ly not mandatory since I am currently flying without this).=0A =0AMore spec
ifically, I have a large main tank from which fuel is pumped into the heade
r. The header is about 5 gallons (one hour of flight time). I typically l
eave my transfer pump on all the time. If it were to stop and I didn't not
ice (which is likely), I have a warning light that will come on at about 2.
5-3 gallons. That leaves me with about 30 minutes to figure out what to do
. If I had known immediately, I would have had 60 minutes. Of course, I h
ave a backup fuel pump which I would immediately switch on. However; it ca
n take some time before seeing the fuel level start to rise. When dealing w
ith a 30 minute window, knowing now versus knowing in 5-10 minutes is a big
deal (at least in terms of my stress level - FYI, I live out west were air
ports are frequently more than 30 minutes apart).=0A=0AJon Finley=0AN314JF
- Q2 - Subaru EJ22=0A[http://www.finleyweb.net/Q2Subaru.aspx] http://www.fi
nleyweb.net/Q2Subaru.aspx=0A =0A =0A=0A-----Original Message-----=0AFrom: "
rampil" =0ASent: Tuesday, April 20, 2010 6:41am=0ATo:
aeroelectric-list(at)matronics.com=0ASubject: AeroElectric-List: Re: Facet pu
=0A=0AGood engineering principles favor measuring th
e actual parameter=0Ayou want, rather than a surrogate, especially when the
re is no=0Areliable one-to-one mapping of one to the other.=0A=0AIn the cas
e of current draw, for example, overheating the coil or dirt=0Ain the mecha
nism will probably change the current draw=0APressure downstream would depe
nd on where the fill hose enters the =0Adownstream tank, if at the bottom,
or at a positive hydrostatic head, the =0Apressure downstream of the pump w
ill stay positive while there is fuel=0Ain the tank.=0A=0AWhat about measur
ing fuel level in the feeding tank, is not that what you=0Areally want to m
ake a decision with? When it reads zero, stop pumping?=0A=0A--------=0AIra
N224XS=0A=0A=0A=0A=0ARead this topic online here:=0A=0Ahttp://forums.matron
================0A=0A=0A=0A
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Good Morning Ira,
I have what I consider to be relatively good fuel gauges in the tanks, but
find that there is at least a ten to fifteen minute window between where
the gauge says empty and it actually will be dry. I do not wish to turn the
pump off too soon and have fuel in the tank that has not been used and I do
not like to run the pump when it is not actually pumping fuel.
It would be very nice to be able to verify the accuracy of the fuel gauge
by noting when the pump stops pumping fuel rather than running the pump
while dry for possibly an extra ten to fifteen minutes every time I utilize the
auxiliary fuel tank.
I do have excellent fuel use measuring capability and what I do now is note
the fuel burned number when I turn on the pump and shut it off when the
amount of fuel known to be in the tank has been burned.
Nevertheless, it would be nice to know within seconds when the tank has run
dry so that the pump could be turned off.
I really would rather not be running the pump when it is not pumping fuel.
Happy Skies,
Old Bob
In a message dated 4/20/2010 7:43:50 A.M. Central Daylight Time,
ira.rampil(at)gmail.com writes:
--> AeroElectric-List message posted by: "rampil"
Good engineering principles favor measuring the actual parameter
you want, rather than a surrogate, especially when there is no
reliable one-to-one mapping of one to the other.
In the case of current draw, for example, overheating the coil or dirt
in the mechanism will probably change the current draw
Pressure downstream would depend on where the fill hose enters the
downstream tank, if at the bottom, or at a positive hydrostatic head, the
pressure downstream of the pump will stay positive while there is fuel
in the tank.
What about measuring fuel level in the feeding tank, is not that what you
really want to make a decision with? When it reads zero, stop pumping?
--------
Ira N224XS
________________________________________________________________________________
| From: | Mike Welch <mdnanwelch7(at)hotmail.com> |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Bob=2C
Pardon me for butting in=2C but from my experience with certificated airp
lanes=2C it is virtually impossible to get a field approval like you're aft
er.
I used to have a 1961 Cessna 172=2C with an O-300 Continental. On those
hot mid-summer California days (100+)=2C my oil temps got well into the red
on climbout!! I checked the accuracy of the gauge=2C and it was correct!
Therefore=2C I wanted to add an oil cooler to my Cessna 172. It didn't c
ome with one=2C but I could get a later model 172 oil cooler to fit. I sen
t off my Form 337 to the local FSDO=2C and their first reaction was "NO!"
Their attitude was "if it didn't come with one=2C it doesn't need one!!"
I was irritated (to say the least)=2C and requested an appeal. They fina
lly relented and said it would be okay. For crying out loud =2C it was jus
t an oil cooler!! (all certified parts=2C too)
My opinion is=3B there ain't no way you can legally add any kind of perma
nent parts to modify to your fuel pump=2C fuel lines=2C or anything else=2C
on a certificated airplane=2C without that approved 337.
Just my opinion.................
Mike Welch
From: BobsV35B(at)aol.com
Date: Tue=2C 20 Apr 2010 09:34:57 -0400
Subject: Re: AeroElectric-List: Re: Facet pumps: Energy vs. Flow
Good Morning Ira=2C
I have what I consider to be relatively good fuel gauges in the tanks=2C bu
t find that there is at least a ten to fifteen minute window between where
the gauge says empty and it actually will be dry. I do not wish to turn the
pump off too soon and have fuel in the tank that has not been used and I d
o not like to run the pump when it is not actually pumping fuel.
It would be very nice to be able to verify the accuracy of the fuel gauge b
y noting when the pump stops pumping fuel rather than running the pump whil
e dry for possibly an extra ten to fifteen minutes every time I utilize the
auxiliary fuel tank.
I do have excellent fuel use measuring capability and what I do now is note
the fuel burned number when I turn on the pump and shut it off when the am
ount of fuel known to be in the tank has been burned.
Nevertheless=2C it would be nice to know within seconds when the tank has r
un dry so that the pump could be turned off.
I really would rather not be running the pump when it is not pumping fuel.
Happy Skies=2C
Old Bob
In a message dated 4/20/2010 7:43:50 A.M. Central Daylight Time=2C ira.ramp
il(at)gmail.com writes:
Good engineering principles favor measuring the actual parameter
you want=2C rather than a surrogate=2C especially when there is no
reliable one-to-one mapping of one to the other.
In the case of current draw=2C for example=2C overheating the coil or dirt
in the mechanism will probably change the current draw
Pressure downstream would depend on where the fill hose enters the
downstream tank=2C if at the bottom=2C or at a positive hydrostatic head=2C
the
pressure downstream of the pump will stay positive while there is fuel
in the tank.
What about measuring fuel level in the feeding tank=2C is not that what you
really want to make a decision with? When it reads zero=2C stop pumping?
--------
Ira N224XS
_________________________________________________________________
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________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Good Afternoon Mike,
Believe it or not I do understand your frustration and the problems that
are faced when dealing with the FAA.
It is my opinion that the vast majority of the folks at FAA want to do a
good job, but are so hamstrung with regulations and paper work that it is
easier to just say no.
However, I have had fairly good luck getting local approvals from my
supervising FSDO.
As I think we can all agree, each FSDO is a kingdom unto itself and what is
easy to get approved at one office may be impossible at another.
Nevertheless, I have gotten several local approvals here locally. I do hold an
A&P
with Inspection Authorization. It does help me know who I should present the
data to and how the presentation should be made.
In general, if we can think of a way to add something that has no chance of
interfering with required equipment, the local approval has a better
chance of being approved.
Once again, the FAA has no obligation to ever issue a local approval. In
fact, if an individual inspector does issue the approval, he is doing it on
his own knowledge and is personally responsible for what happens. In many
ways it is surprising that any FAA inspector ever issues a local approval.
He/she has no obligation to do so. It is just a privilege he has been
accorded. Failure to do so does not hurt his career at all, but making a dumb
approval could end his career.
Happy Skies,
Old Bob
In a message dated 4/20/2010 12:37:05 P.M. Central Daylight Time,
mdnanwelch7(at)hotmail.com writes:
Bob,
Pardon me for butting in, but from my experience with certificated
airplanes, it is virtually impossible to get a field approval like you're after.
I used to have a 1961 Cessna 172, with an O-300 Continental. On those hot
mid-summer California days (100+), my oil temps got well into the red on
climbout!! I checked the accuracy of the gauge, and it was correct!
Therefore, I wanted to add an oil cooler to my Cessna 172. It didn't come
with one, but I could get a later model 172 oil cooler to fit. I sent off
my Form 337 to the local FSDO, and their first reaction was "NO!" Their
attitude was "if it didn't come with one, it doesn't need one!!"
I was irritated (to say the least), and requested an appeal. They finally
relented and said it would be okay. For crying out loud , it was just an
oil cooler!! (all certified parts, too)
My opinion is; there ain't no way you can legally add any kind of
permanent parts to modify to your fuel pump, fuel lines, or anything else, on
a
certificated airplane, without that approved 337.
Just my opinion.................
Mike Welch
________________________________________________________________________________
| Subject: | Re: switch breaker on ALT field |
| From: | "rckol" <rckol(at)kaehlers.com> |
Switch breakers will function for this application.
I have read conflicting reports about the long term reliability of these. Some
folks end up tearing them out because they don't hold up and others have no trouble
with them. Sorry, I don't have any brand specific recommendations. I
am not going to use them.
Dick
--------
rck
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=295024#295024
________________________________________________________________________________
| Subject: | S704-1 on Hot Side of Firewall? |
| From: | "Noah" <sgninc(at)cox.net> |
I requested the spec sheet for the S704-1 relay from B&C, and it is a Tyco T9A
with an operating temp limit of 85C (185F). This seems a bit low for mounting
in the engine compartment on the firewall. where I had been planning to mount
it. I called B&C to ask them if they recommended mounting these in the engine
compartment and the gentleman I spoke with was not sure - he recommended a post
here.
Anybody know what the firewall temps can climb to?? Anybody mounted one of these
firewall forward in an RV and had problems? Or had it last 2000 hours without
issue??
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=295030#295030
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: S704-1 on Hot Side of Firewall? |
At 05:36 PM 4/20/2010, you wrote:
>
>I requested the spec sheet for the S704-1 relay from B&C, and it is
>a Tyco T9A with an operating temp limit of 85C (185F). This seems a
>bit low for mounting in the engine compartment on the firewall.
>where I had been planning to mount it. I called B&C to ask them if
>they recommended mounting these in the engine compartment and the
>gentleman I spoke with was not sure - he recommended a post here.
>
>Anybody know what the firewall temps can climb to?? Anybody mounted
>one of these firewall forward in an RV and had problems? Or had it
>last 2000 hours without issue??
It will be fine. These devices and their close
cousins are used under the hood of motor vehicles
and they're fine.
The various companies I've worked for have done
numerous studies of temperature under the cowl
and found that nothing gets really all that hot
as long as it's not exposed to direct infra-red
radiation from stacks (particularly turbochargers).
I've seen some RG battery cases melted because they
were too close to exhaust pipes.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: switch breaker on ALT field |
At 03:50 PM 4/20/2010, you wrote:
>
>Switch breakers will function for this application.
>
>I have read conflicting reports about the long term reliability of
>these. Some folks end up tearing them out because they don't hold
>up and others have no trouble with them. Sorry, I don't have any
>brand specific recommendations. I am not going to use them.
The mil-qualified sw/breakers are fine. Actually, the
P&B W31 series are reasonably decent too. There's about
80K in service in Bonanzas and Barons since way back
when . . . and yes, a few have failed in a way that
put smoke in the cockpit . . . but those were the 30A
devices that control electric prop de-ice.
Obviously, you can't get the features in single
switches of any kind that are offered in the progressive-
transfer 2-pole toggles (2-10, 2-50, 2-70) but if your
design goals don't require this feature, then the
single switches will do.
Now, having said that, I'm not sure I'd recommend
the W31 used upstream of a crowbar ov protection system
that I designed. I've not studied the trip dynamics of
this device in that application. The miniature TI/Klixon
style breakers have been paired with our crowbar ov
systems by the thousands with good service histories.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Facet pumps: Energy vs. Flow |
| From: | "user9253" <fran4sew(at)banyanol.com> |
A "tank empty switch" can be made with a magnet attached to a float inside of the
tank. A magnetic reed switch on the outside of the tank will close when the
magnet gets close to it. Of course this is only legal for home-built aircraft.
The only thing visible on the outside of the tank will be a pair of wires
with heat-shrink on the end that the covers the switch. Perhaps there are similar
switches commercially available.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=295073#295073
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Facet pumps: Energy vs. Flow |
Good Morning Joe,
Another great idea! This list is resourceful.
For my purposes, the fuel gauge I have does a good job as far as telling me
when my usable fuel is out of the tank. Admittedly, there are times when
four or five minutes of fuel will make a difference and if the flight is
planned to land with the FAA suggested thirty minute minimum planned fuel
reserve, five more minutes will make a difference to me.
However, I rarely cut fuel that close so my effort is oriented more toward
reducing the time the pump will be operating dry. That is why I am more
interested in finding out when the pump is pumping nothing but air. So far,
the best answer appears to be the optical monitoring of fuel flow. I
originally thought pressure would do the trick, but as many have pointed out,
there may not be enough head pressure to allow consistent measurable
April 05, 2010 - April 21, 2010
AeroElectric-Archive.digest.vol-jl