AeroElectric-Archive.digest.vol-ht
April 11, 2008 - April 22, 2008
>Folks,
>
>I'm using the Ray Allen electric trim and their stick grips in my
>GlaStar. I'm using shielded two-conductor cable from the PTT switch to
>the intercom. I need to splice that cable and originally used Bob's
>soldered lap splicing technique but kept the exposed wires very short to
>be able to replace the shield. Long story short -- one of the wires
>shorted to the shield so I had a "stuck mic".
>
>My specific question is: what's the best way to replace the shield after
>splicing shielded wire? To do it right this time, I'll have to expose
>about 2" - 3" of each wire.
There is no electronic value in having this wire be
shielded. Therefore, no value in attempting to maintain
shield integrity in a splice. Prepare the end as shown
here:
http://aeroelectric.com/articles/shldwire/shldwire.html
and splice onto the ends. Cover joints with heat shrink.
You can use a twisted pair of 22AWG wires to extend the
shielded conductor.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Jim" <jjewell(at)telus.net> |
If you are looking for a well built and finely finished RV6-A or you
know someone who is, mine will sometime soon be advertized for sale.
For sale by builder:
TT 50 Hr.
Aerosport-Power O-360-A1A 50 Hr.
Hartzell C/S prop -50 Hr.
Oil filter
Aeroelectric connection Z-11 based wiring
1 Slick mag 1 electronic ign.
55 Amp. Nippon Denzo alternator
Automotive geared starter with extra new spare starter
Navaid wing leveler (accepts handheld GPS waypoints)
Altitude hold
Dynon EFIS D10-A +battery and remote compass module
Analog, airspeed, altitude,fuel gauges
Sirs compass
Rocky mountain Instruments uMonitor & uEncoder also with remote compass
module
SL-40 com - SL-70 Xponder
PM-3000 stereo intercom
Electric flaps
Elevator and aileron trims on left stick
Sliding canopy
Professionally upholstered Conforfoam seats
Removable control panel with removable instrument section.
Custom built aluminium floors.
Nose wheel fork mod done.
Professionally painted yellow (very visible), add decor (stripes etc.)
per taste
Many painstaking hours spent on rigging, fit and finish.
First annual coming up.
I have yet to put up a website, If you are interested in further
information I will send requested info and photos.
Asking $95000.00
Jim in Kelowna B.C.
Contact:
jjewell AT telus.net
Ph- (250) 861-8706
________________________________________________________________________________
| Subject: | Re: Securing Ends of Wires in Wing for Later Use |
| From: | "nukeflyboy" <flymoore(at)charter.net> |
This won't help the original question, but if you have run conduit then remember
this trick. A vacuum cleaner stuck on one end can be used to "pull" a string
through the full length of the conduit from the other end. Then just attach
the wires and pull them through using the string.
--------
Dave
RV-6 flying
RV-10 QB building
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176307#176307
________________________________________________________________________________
| Subject: | Alternate Feed Switch, is it a Master Switch?? |
| From: | "Leo Holler" <leoh(at)gci.net> |
Help! Am working on a new electrical system design (pretty much a standard Z-11)
for a complete re-wire of a certified ship. A friend tells me that a certified
aircraft can only have one Master Switch per FAA regs. Is the "Alternate Feed"
switch for the Endurance Bus considered a Master Switch? If so, how does
it reconcile with any regs? Or, is my friend wrong? I have read Sec. 23.1361,
regarding Master Switch arrangement, and I'm not totally comfortable in my interpretation
of what is being said. The section seems to infer that more than one
switch can be incorporated into a Master Switch arrangement, but with some
restrictions. Can someone shed some light on me regarding this matter?
I have been planning to locate the Alternate Feed switch immediately adjacent to
the main Master Switch and under a switch guard. Presumably, both switches would
only be on simultaneously for the short time after energizing the Endurance
Bus via the Alternate Feed and turning the main Master off after an alternator
or battery contactor failure.
Per 23.1361, am I restricted to no more than a 5 amp total load on the Endurance
Bus (that should be plenty)? Would I also be restricted to no more than a 5
amp protective device for the bus feed? My bus feed wire will be about 8" long.
Thanks to any of you "Masters" for any enlightenment you can share.
The FAR quoted above can be found at:
http://www.risingup.com/fars/info/part23-1361-FAR.shtml
Leo
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176349#176349
________________________________________________________________________________
| From: | <gmcjetpilot(at)yahoo.com> |
The AMP meter is really a VOLT METER. Yep it has nothing to do with AMPS. (There
is an AMP and VOLT relation).
How does it work. The shunt causes a voltage drop across the shunt (due to resistance).
That resistance is a known calibrated value. The volt gauge is reads
volt drop. Since voltage drop is proportional to current (amps) the gauge can
read the volt drop as current or amps, as follows:
This is the famous OHMS law:
V = I x R
OR
Volts = Current (amps) X Resistance (ohms)
So what?
We know a shunt is "calibrated" to drop a certain volt for every every amp of
current. Shunts vary, but a typical 50 amp shunt has a 50 millivolt drop at 50
amps.
If you have 50 amps at 14 volts entering the shunt, the volts leaving the shunt
at 50 amps will be 50 millivolts (0.050v) lower or 13.95 volts.
One millivolt drop = one amp. So you need a gauge that is labeled from 0 to 50
amps (but has a range from 0 to 0.050 volts).
With a volt gage that reads millivolts from 0 to 50 millivolts (but labeled amps)
we have an AMP METER!
Again the meter is measuring voltage drop not amps. It just happens OHMS LAW
is handy and linear (usually); where current and volts are proportional based
on the resistance of the shunt.
Shunts can have higher or lower resistance. Not all have the 1 amp to 1 millivolts
ratio. That is OK as long as the scale and range of the gauge (analog or
digital) compatible or calibrated for that shunt. The 1 amp to 1 millivolt ratio
is handy since many volt gauges are calibrated in millivolts. Mini digital
panel volt meters are usually read millivolts.
You can make your own AMP meter from a small digital volt meter and a piece of
wire that has the 0.001 volt/amp (Ohm) resistance.
I hope that helps. George
__________________________________________________
________________________________________________________________________________
| From: | "Emond" <d_emond(at)mweb.co.za> |
| Subject: | Re: Music Inputs |
I had a music jack wired into my system. My audio panel is a Garmin 340. I
have a sonyericcson mobile phone with walkman capability. What I find is
that with the walkman at max volume output the sound through the headphones
is reasonable, engine off on the ground. However with the engine running at
cruise I can barely hear the music. Are there settings on the system I
should check ??
Dave Emond
________________________________________________________________________________
| From: | "earl_schroeder(at)juno.com" <earl_schroeder(at)juno.com> |
| Subject: | Re: Music Inputs |
Hi Dave, If you want to add a another 'device', I've used one described in the following link: http://www.boostaroo.com/ Earl
Dave wrote:
I had a music jack wired into my system. My audio panel is a Garmin 340. I
have a sonyericcson mobile phone with walkman capability. What I find is
that with the walkman at max volume output the sound through the headphones
is reasonable, engine off on the ground. However with the engine running at
cruise I can barely hear the music. Are there settings on the system I
should check ??
Dave Emond
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Alternate Feed Switch, is it a Master Switch?? |
>
>Help! Am working on a new electrical system design (pretty much a standard
>Z-11) for a complete re-wire of a certified ship. A friend tells me that a
>certified aircraft can only have one Master Switch per FAA regs.
Ask him to cite the regulation. I've never read it anywhere.
We have lots of switches in TC aircraft OTHER than the DC
POWER MASTER switch that re-organize bus structures and/or
control alternative pathways to power sources. For example,
many offerings in recent years at HawkerBeech have a "clearance
delivery" switch that allows one to power up one radio directly
from the battery for the purpose of getting ATIS and Clearance
Delivery before powering up the whole airplane.
> Is the "Alternate Feed" switch for the Endurance Bus considered a
> Master Switch? If so, how does it reconcile with any regs? Or, is my
> friend wrong? I have read Sec. 23.1361, regarding Master Switch
> arrangement, and I'm not totally comfortable in my interpretation of what
> is being said. The section seems to infer that more than one switch can
> be incorporated into a Master Switch arrangement, but with some
> restrictions. Can someone shed some light on me regarding this matter?
>
>I have been planning to locate the Alternate Feed switch immediately
>adjacent to the main Master Switch and under a switch guard. Presumably,
>both switches would only be on simultaneously for the short time after
>energizing the Endurance Bus via the Alternate Feed and turning the main
>Master off after an alternator or battery contactor failure.
>
>Per 23.1361, am I restricted to no more than a 5 amp total load on the
>Endurance Bus (that should be plenty)? Would I also be restricted to no
>more than a 5 amp protective device for the bus feed? My bus feed wire
>will be about 8" long.
>
>Thanks to any of you "Masters" for any enlightenment you can share.
The 5-Amp rule presupposes that the battery feeder to the
E-bus Alternate Feed switch is LONG . . . 5A is the rule-
of-thumb for limiting always-hot feeders directly from
the battery that might pose a post-crash risk of fire.
It's pretty much a hip-shot number. Give me control over
the conditions and I can light off gasoline with a 1A
feeder and not open the breaker.
If you NEED to protect the alternate feed at more than
5A, then install a "mini-battery contactor" right at
the battery bus as suggested in:
http://www.aeroelectric.com/Pictures/Schematics/E-BusFatFeed.gif
http://www.aeroelectric.com/PPS/DCPwr/E-Bus/E-Bus_Heavy.pdf
This provides for local disconnect of feeders protected
at more than 5A.
>The FAR quoted above can be found at:
>
>http://www.risingup.com/fars/info/part23-1361-FAR.shtml
Okay, let's look at it:
Sec. 23.1361 - Master switch arrangement.
(a) There must be a master switch arrangement to allow ready disconnection
of EACH electric power source from power distribution systems, except as
provided in paragraph (b) of this section.
Note that the rules allow for MORE than one power source, hence more
than one switch . . .
The point of disconnection must be adjacent to the sources controlled by
the switch arrangement.
Yup, unless the feeder is limited to 5A or less as described below:
If separate switches are incorporated into the master switch arrangement, a
means must be provided for the switch arrangement to be operated by one
hand with a single movement.
Yeah . . . this is a tad silly. If one is concerned about getting
switching ALL potential hazards off with switches as a single movement
then the magneto switches should probably be included under the
one-movement-does-all mechanism. In the suggested switch layouts
shown in
http://www.aeroelectric.com/PPS/Mechanical/Switches.pdf
. . . switches that control all power including ignition are
grouped at one end of the array. Easy to locate and easy to get
turned OFF in a timely manner when circumstances call for it.
For a TC aircraft, you can craft a hinged "crash bar" that
provides the requested one-stroke operation of adjacent switches.
I had a discussion some years ago with a 172 owner who was
wanting to do the same thing you're doing. We discussed using
switch guards over adjacent switches and ganging them together
with a bonded plate so that slapping them down opened both
switches.
Now, this one-hand-operation is somehow magically ignored in
some TC aircraft where emergency batteries are used to power
up essential appliances . . . they are generally not fitted with
or even arranged such that one-handed operation is possible.
(b) Load circuits may be connected so that they remain energized when the
master switch is open, if the circuits are isolated, or physically
shielded, to prevent their igniting flammable fluids or vapors that might
be liberated by the leakage or rupture of any flammable fluid system; and
(1) The circuits are required for continued operation of the engine; or
(2) The circuits are protected by circuit protective devices with a rating
of five amperes or less adjacent to the electric power source.
(3) In addition, two or more circuits installed in accordance with the
requirements of paragraph (b)(2) of this section must not be used to supply
a load of more than five amperes.
(c) The master switch or its controls must be so installed that the switch
is easily discernible and accessible to a crewmember.
Since your proposed changes are not part of the original
TC on the as-built airplane, you're going to have to jump
STC/337 hoops. So this is between you and your local
regulators. What you're proposing has been done before
and is not a really big deal. It's just slight rearrangement
of the design goals that have been similarly addressed with
additions of the "clearance delivery" switch on modern
aircraft.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Alternate Feed Switch, is it a Master Switch?? |
| From: | "Leo Holler" <leoh(at)gci.net> |
Thanks Bob for an exceptional and thorough response. You very clearly took the
most of the "fog" out of my feeble interpretation of Section-23-1361. I'll be
able to better make my 337(Field Approval) case to FAA now, as well as educate
my friend.
> The point of disconnection must be adjacent to the sources controlled by
> the switch arrangement.
>
> Yup, unless the feeder is limited to 5A or less as described below:
Does the above mean that the 5A rule applies only if there is no disconnection
adjacent to the source? Also, do you consider the 8" unprotected run from battery
to Alternate Feed switch to be excessive? If so, I can fuse it, or add the
mini-contactor as you have suggested. Also, I have heard that new Cessnas have
Essential/Endurance buses installed. Have you or anyone else heard of this and,
if so, how did they handle the Master Switch arrangement? A local Cessna dealer
hinted that I could get their schematic by buying the CD for several hundred
dollars or by buying a new aircraft. [Shocked] This forum seems much more
user friendly. :D
Thanks again.
Leo
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176423#176423
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Alternate Feed Switch, is it a Master Switch?? |
>
>Thanks Bob for an exceptional and thorough response. You very clearly took
>the most of the "fog" out of my feeble interpretation of Section-23-1361.
>I'll be able to better make my 337(Field Approval) case to FAA now, as
>well as educate my friend.
>
>
> > The point of disconnection must be adjacent to the sources controlled by
> > the switch arrangement.
> >
> > Yup, unless the feeder is limited to 5A or less as described below:
>
>
>Does the above mean that the 5A rule applies only if there is no
>disconnection adjacent to the source?
Yes. Things like hour meters, clocks, dome lights, etc have
been attached directly to the battery and protected with 5A
breakers or fuses for decades. This allows a battery fed,
always hot wire to snake its way through the airplane to
do the intended task irrespective of whether or not the
battery master switch was ON.
>Also, do you consider the 8" unprotected run from battery to Alternate
>Feed switch to be excessive?
Not sure about this question. The battery bus feeds should
always be protected by fuses or breakers, no matter how long.
The 8" rule is to avoid fusing things like jumpers that run
between the (+) side of a capacitor. bus isolation diode
(or similar device) and the power source. This is a special
case that doesn't apply to this conversation.
Whether your e-bus is simply switched or run through a
mini-battery contactor, it still gets protection right
at the battery.
> If so, I can fuse it, or add the mini-contactor as you have suggested.
I would recommend you go the mini-contactor route and
wire with 14AWG wire no matter what size fuse/breaker you
select. Even if you can get by with a 5A protected feeder
today, you may wish to upgrade it later. This is easily
accomplished if the local disconnect (relay) and wire
(14AWG) are already in place. The breaker or fuse can be
elevated to as high as 15A at a later time without taking
a hatchet to the wire bundles.
>Also, I have heard that new Cessnas have Essential/Endurance buses
>installed. Have you or anyone else heard of this and, if so, how did they
>handle the Master Switch arrangement?
I can find out. It would be pretty cool if they do this
now. About two years after I handed out several copies of the
'Connection to folks at the single-engine electrical engineering
group, a firewall mounted, single point ground system was
installed on production aircraft. I'll ask around.
> A local Cessna dealer hinted that I could get their schematic by buying
> the CD for several hundred dollars or by buying a new aircraft. [Shocked]
> This forum seems much more user friendly. :D
Yeah . . . I can get one for the asking. I'll see
what I can do.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Alternate Feed Switch, is it a Master Switch?? |
Before Cessna bought Columbia you could get the Columbia 400 wiring diagrams
from their web site. (have not checked lately). They have dual bus, dual
alternator with an essential bus diode fed from either bus.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Leo
Holler
Sent: Saturday, April 12, 2008 1:53 PM
Subject: AeroElectric-List: Re: Alternate Feed Switch, is it a Master
Switch??
Thanks Bob for an exceptional and thorough response. You very clearly took
the most of the "fog" out of my feeble interpretation of Section-23-1361.
I'll be able to better make my 337(Field Approval) case to FAA now, as well
as educate my friend.
> The point of disconnection must be adjacent to the sources controlled by
> the switch arrangement.
>
> Yup, unless the feeder is limited to 5A or less as described below:
Does the above mean that the 5A rule applies only if there is no
disconnection adjacent to the source? Also, do you consider the 8"
unprotected run from battery to Alternate Feed switch to be excessive? If
so, I can fuse it, or add the mini-contactor as you have suggested. Also, I
have heard that new Cessnas have Essential/Endurance buses installed. Have
you or anyone else heard of this and, if so, how did they handle the Master
Switch arrangement? A local Cessna dealer hinted that I could get their
schematic by buying the CD for several hundred dollars or by buying a new
aircraft. [Shocked] This forum seems much more user friendly. :D
Thanks again.
Leo
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176423#176423
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
gmcjetpilot(at)yahoo.com wrote:
> The AMP meter is really a VOLT METER. Yep it has nothing to do with AMPS. (There
is an AMP and VOLT relation).
>
>
Aahh! But is it? Maybe the VOLT meter is really an AMP METER!!
If using a swinging arm type meter, the voltage across the inputs drives
a current that energizes an electromagnet, the forces the deflection.
You're using current to measure a voltage, that's caused by the current
across the shunt, which is caused by a voltage.
Aahiiieee!!
8*)
--
http://www.ronpaultimeline.com
________________________________________________________________________________
| Subject: | Re: Music Inputs |
| From: | "Martin Pohl" <mpohl(at)pohltec.ch> |
Earl, thank you for the great link. I was looking for exactly such a device. Do
you know if there is any amplifier around with an additional volume control knob?
Martin
--------
Martin Pohl
Zodiac XL QBK
8645 Jona, Switzerland
www.pohltec.ch/ZodiacXL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176515#176515
________________________________________________________________________________
| Subject: | Re: Music Inputs |
| From: | "Martin Pohl" <mpohl(at)pohltec.ch> |
Just found this: http://www.minidisc.org/headbanger.html
Will try to get it running with my Harman Kardon Drive Play iPod Controller, Flightcom
Intercom 403stereo and Lightspeed 3G headphones.
Martin
--------
Martin Pohl
Zodiac XL QBK
8645 Jona, Switzerland
www.pohltec.ch/ZodiacXL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176516#176516
________________________________________________________________________________
| From: | "Dustin Paulson" <dustinp(at)hughes.net> |
| Subject: | Re: Music Inputs |
Dave,
I just had this same question, after a recent discussion by Vern Little
about the AMX-2 Audio Mixer Amplifier, and Vern was nice enough to send
me the following information when I inquired about using the AMX-2 to
solve this issue..
Apparently Garmin added a pre-amp for the music inputs on the 340 to
help solve just the problem you describe, and that I also have.
They came up with a modification called Mod 2 first, in which you place
in pin in the #15 position of the J-2 plug on the back of the GMA 340,
and connect it directly to ground to activate this pre-amp.
Apparently sometime later they came out with the Mod 5, which allows you
to install a wire and pin in the same #15 position, and connect it to a
switch that is connected to ground so that you can have the pre-amp
either off or on depending on whether what you have plugged into the
music input needs further amplification or not. This switched ground
also apparently helped eliminate the amplification of other "noises" in
the system, by being able to turn it off when the pre-amp wasn't needed
for the music input. The Garmin notes state this switch can only be
installed in units with Mod 5.
So, you will need to find out if you have either of those Mods. Vern
said that it was probably listed on a tag on the unit, but I was able to
find it on some paper work that had come back with the unit after some
factory repair work had been done, that showed my unit had the Mod 5
installed. Now I need to find a reasonable source for a high density pin
crimper.
I have Steins 4-way indent crimper for the standard density pins, but
not the high density.
I need a 15 pin high density connector for another Mod I need to make to
get my 430W to talk nice to my GRT EFIS through my Approach Avionics
Hub.
Stein has the HD pins, but not the 15 pin HD connectors I need.
So if anyone has a good ( read cheap ) source for the high density pins,
15 pin HD connectors, and tools, I'd like to hear about them.
If not, Approach will do the mods I need for a price that may be less
than investing in the tools, but it would be nice to have the tools for
future needs too.
Thanks
Dustin Paulson
I had a music jack wired into my system. My audio panel is a Garmin 340.
I
have a sonyericcson mobile phone with walkman capability. What I
find is
that with the walkman at max volume output the sound through the
headphones
is reasonable, engine off on the ground. However with the engine
running at
cruise I can barely hear the music. Are there settings on the
system I
should check ??
Dave Emond
________________________________________________________________________________
| From: | <gmcjetpilot(at)yahoo.com> |
| Subject: | Re: AeroElectric-List Digest: 8 Msgs - 04/12/08 |
Dave Garmin has a AUDIO GAIN adjustment you can control. Good news. Not sure if
you model has that gain or volume, but do know some Garmin audio panels do.
ANY WAY Garmin (some models) are adjustable. Some req you go into a menu.
Other intercoms that don't have adjustment can benefit from a headphone amp or
small preamp to feed the intercom. iPods and CD players have small amps that
are made to drive small headphones or earbuds. They tend to be a little under
powered to drive some intercoms. Also the output from portable music devices
is 16-32 ohm impedance. The input impedance to most intercoms is 600 ohms. The
mis match does not help either.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
From: "Emond" <d_emond(at)mweb.co.za>
Subject: AeroElectric-List: Re: Music Inputs
I had a music jack wired into my system. My audio panel is a Garmin
340. I
have a sonyericcson mobile phone with walkman capability. What I find
is
that with the walkman at max volume output the sound through the
headphones
is reasonable, engine off on the ground. However with the engine
running at
cruise I can barely hear the music. Are there settings on the system I
should check ??
Dave Emond
__________________________________________________
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
>
>
>gmcjetpilot(at)yahoo.com wrote:
>>The AMP meter is really a VOLT METER. Yep it has nothing to do with AMPS.
>>(There is an AMP and VOLT relation).
>>
>>
>
>Aahh! But is it? Maybe the VOLT meter is really an AMP METER!!
>If using a swinging arm type meter, the voltage across the inputs drives a
>current that energizes an electromagnet, the forces the deflection.
>You're using current to measure a voltage, that's caused by the current
>across the shunt, which is caused by a voltage.
>
>Aahiiieee!!
A very astute observation sir. Allowing a coil
of wire to move within the field of a permanent magnet
was the brainchild of a fine fellow named D'arsonval
who conceived the design about 130 years ago. There's
an excellent description of the details of this idea
offered over several pages beginning at:
http://www.tpub.com/neets/book3/7.htm
Hit the "-> next" buttons to access the series.
One may also craft a moving magnet instrument . . .
a good example is Van's ammeter. Unlike the more
fragile and difficult to calibrate moving coil
movement typical of:
http://www.aeroelectric.com/Pictures/Instruments/Loadmeter_2.jpg
Vans ammter shown at:
http://www.aeroelectric.com/Pictures/Instruments/VAM10_Interior_View
moves a barrel shaped magnet in the center of TWO coils
positioned at right angles to each other. This movement
doesn't need springs and is NOT calibrated with respect
to current flowing in the coils. In this case
two coils are excited with a current proportional
to the sine and cosine of the applied stimulus. The magnet
and pointer are often free to rotate 360 degrees. Van's
instrument is "pegged" at -45 amps and has a light spring
that drives the pointer to the peg when the instrument is
powered down. But you could remove the peg and spring.
The pointer would rotate freely and still properly indicate
the mechanical result of the ratio of two currents applied
to the coils. This style of meter movement can be used to
drive something like a compass card for displaying a
heading not unlike that offered by the DG.
This instrument is interesting because it can be
electronically conditioned to display a host of stimuli
and it takes advantage of the full rotational scale
of the instrument. D'arsonval movements get VERY
hard to build beyond 90 to 110 degrees of pointer
swing.
Because they deal with the results of a magnetic
interaction between coil(s) of wire and fixed magnets
both instruments are indeed displays of the effects
of CURRENT.
However, if one considers the internal resistance of
the instrument as being part of the overall circuit,
the raw device can be used to display the effects
of very small voltages. A good example is the classic,
non-amplified CHT instrument. An example is shown
here:
http://www.aeroelectric.com/Pictures/Instruments/CHT%20Gauge.jpg
This puppy reads full scale when something on the order
of 7 MILLIVOLTS is applied to its terminals. This is
the voltage generated by K-type thermocouple wire
at 350F. In this case, the moving coil can be crafted
of few turns of relatively large wire (low resistance)
because while a thermocouple doesn't offer much VOLTAGE,
it is a very low impedance source of energy and can
produce considerable CURRENT at the relatively small
voltage.
All moving coil devices are dependent upon the force
against a spring which is proportional to the current
flowing in a coil of wire. Of course the coil has resistance
of its own so any basic meter movement calibrated for
the measurement of a current may also be said to be
a "voltmeter" . . . typically, rudimentary movements will
indicate full scale with voltages on the order of 10
to 200 millivolts. The instruments designed to work in
conjunction with shunts are generally crafted so that
the CURRENT induced in the coil produces full scale
torque when 50 milliVOLTS (standard shunt calibration)
is applied to the terminals.
Van's instrument is fitted with electronics such that
the stuff sensed at the input terminals is indeed
a voltage . . . the considerable current required
to position the pointer comes from the electronics
power supply and not from the voltage stimuli being
monitored.
I've done some preliminary testing on the Van's
ammeter . . . by modern aviation design goals it
is exceedingly sensitive to local RF fields. I'm
working on an article to explore this condition.
I'll also see if I can craft an easily fabricated
filter or shield as a workaround for this product's
shortcomings.
Bob . . .
________________________________________________________________________________
| From: | "Don Curry" <currydon(at)bellsouth.net> |
| Subject: | 90-Degree Adapter for Avionics Cooling Fan Hose |
Does anybody know where to get a 90-degree elbow adapter to fit on the
cooling fan port on the backplate of a KX-165? I'm using Cyclone hose and
it is too stiff to make the bend (or kinks) in the space available. I've
checked all the usual places (Spruce, Chief, etc) and can't find anything.
Thanks, Don
________________________________________________________________________________
| Subject: | Re: 90-Degree Adapter for Avionics Cooling Fan Hose |
| From: | Ron Quillin <rjquillin(at)gmail.com> |
At 08:27 4/13/2008, you wrote:
>Does anybody know where to get a 90-degree elbow adapter to fit on the
>cooling fan port on the backplate of a KX-165? I'm using Cyclone hose and
>it is too stiff to make the bend (or kinks) in the space available. I've
>checked all the usual places (Spruce, Chief, etc) and can't find anything.
>Thanks, Don
Don't know if it's applicable for you, but I used a 5/8" copper pipe
ELL on the back of a KNS-80.
Ron Q.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Shunts (broken link fixed) |
>
>
>gmcjetpilot(at)yahoo.com wrote:
>>The AMP meter is really a VOLT METER. Yep it has nothing to do with AMPS.
>>(There is an AMP and VOLT relation).
>>
>
>Aahh! But is it? Maybe the VOLT meter is really an AMP METER!!
>If using a swinging arm type meter, the voltage across the inputs drives a
>current that energizes an electromagnet, the forces the deflection.
>You're using current to measure a voltage, that's caused by the current
>across the shunt, which is caused by a voltage.
>
>Aahiiieee!!
A very astute observation sir. Allowing a coil
of wire to move within the field of a permanent magnet
was the brainchild of a fine fellow named D'arsonval
who conceived the design about 130 years ago. There's
an excellent description of the details of this idea
offered over several pages beginning at:
http://www.tpub.com/neets/book3/7.htm
Hit the "-> next" buttons to access the series.
One may also craft a moving magnet instrument . . .
a good example is Van's ammeter. Unlike the more
fragile and difficult to calibrate moving coil
movement typical of:
http://www.aeroelectric.com/Pictures/Instruments/Loadmeter_2.jpg
Vans ammter shown at:
http://www.aeroelectric.com/Pictures/Instruments/VAM40_Interior_View.jpg
moves a barrel shaped magnet in the center of TWO coils
positioned at right angles to each other. This movement
doesn't need springs and is NOT calibrated with respect
to current flowing in the coils. In this case
two coils are excited with a current proportional
to the sine and cosine of the applied stimulus. The magnet
and pointer are often free to rotate 360 degrees. Van's
instrument is "pegged" at -45 amps and has a light spring
that drives the pointer to the peg when the instrument is
powered down. But you could remove the peg and spring.
The pointer would rotate freely and still properly indicate
the mechanical result of the ratio of two currents applied
to the coils. This style of meter movement can be used to
drive something like a compass card for displaying a
heading not unlike that offered by the DG.
This instrument is interesting because it can be
electronically conditioned to display a host of stimuli
and it takes advantage of the full rotational scale
of the instrument. D'arsonval movements get VERY
hard to build beyond 90 to 110 degrees of pointer
swing.
Because they deal with the results of a magnetic
interaction between coil(s) of wire and fixed magnets
both instruments are indeed displays of the effects
of CURRENT.
However, if one considers the internal resistance of
the instrument as being part of the overall circuit,
the raw device can be used to display the effects
of very small voltages. A good example is the classic,
non-amplified CHT instrument. An example is shown
here:
http://www.aeroelectric.com/Pictures/Instruments/CHT%20Gauge.jpg
This puppy reads full scale when something on the order
of 7 MILLIVOLTS is applied to its terminals. This is
the voltage generated by K-type thermocouple wire
at 350F. In this case, the moving coil can be crafted
of few turns of relatively large wire (low resistance)
because while a thermocouple doesn't offer much VOLTAGE,
it is a very low impedance source of energy and can
produce considerable CURRENT at the relatively small
voltage.
All moving coil devices are dependent upon the force
against a spring which is proportional to the current
flowing in a coil of wire. Of course the coil has resistance
of its own so any basic meter movement calibrated for
the measurement of a current may also be said to be
a "voltmeter" . . . typically, rudimentary movements will
indicate full scale with voltages on the order of 10
to 200 millivolts. The instruments designed to work in
conjunction with shunts are generally crafted so that
the CURRENT induced in the coil produces full scale
torque when 50 milliVOLTS (standard shunt calibration)
is applied to the terminals.
Van's instrument is fitted with electronics such that
the stuff sensed at the input terminals is indeed
a voltage . . . the considerable current required
to position the pointer comes from the electronics
power supply and not from the voltage stimuli being
monitored.
I've done some preliminary testing on the Van's
ammeter . . . by modern aviation design goals it
is exceedingly sensitive to local RF fields. I'm
working on an article to explore this condition.
I'll also see if I can craft an easily fabricated
filter or shield as a workaround for this product's
shortcomings.
Bob . . .
--
Date: 4/12/2008 11:32 AM
incoming mail is certified Virus Free.
Checked by AVG.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Palvary" <paula.alvary(at)verizon.net> |
| Subject: | Terra 250 transponder for sale |
Excellent condition transponder with tray and FAA req'd Mod 5 AD done.
I purchased this transponder a year ago from Ebay. The project fell
through so I never installed it nor tested it, but was sold to me "in
perfect working condition". The unit has an "Authorization for Return
to Service" tag from Terra Corporation dated May 22,1995. I payed a
lot for this unit ($670) because it is one of the few of the type that
is
legal to use because it had the Mod 5 AD done. The great benefit of
these TRT250 units is that they are very compact and lightweight, like
the Microair or Becker units. Perfect for the cramped panel of a VFR
Long or Vari.
--Jose
________________________________________________________________________________
| From: | "Emrath" <emrath(at)comcast.net> |
| Subject: | Re: Music Inputs |
Check your installation. There is a "high music gain" feature that required
a grounding of Pin J2-15 and provide a lot of gain. I'm still building so
I haven't run the engine yet, but this greatly improved my volume. Also, I
have a ANC David Clark and for some reason turning on the ANC really
improved the sound quality and gave a boost to the low end!
Good Luck.
Marty
From: "Emond" <d_emond(at)mweb.co.za>
Subject: AeroElectric-List: Re: Music Inputs
I had a music jack wired into my system. My audio panel is a Garmin 340. I
have a sonyericcson mobile phone with walkman capability. What I find is
that with the walkman at max volume output the sound through the headphones
is reasonable, engine off on the ground. However with the engine running at
cruise I can barely hear the music. Are there settings on the system I
should check ??
Dave Emond
________________________________________________________________________________
| From: | "Sam Hoskins" <shoskins(at)MCHSI.COM> |
| Subject: | Re: 90-Degree Adapter for Avionics Cooling Fan Hose |
I used the cooling blast hose, from Vans, to cool my mags. It's cheap and
easy to form.
See it here: *http://tinyurl.com/4mbget
Sam Hoskins
Quickie Q-200
*
On Sun, Apr 13, 2008 at 10:27 AM, Don Curry wrote:
> currydon(at)bellsouth.net>
>
>
> Does anybody know where to get a 90-degree elbow adapter to fit on the
> cooling fan port on the backplate of a KX-165? I'm using Cyclone hose and
> it is too stiff to make the bend (or kinks) in the space available. I've
> checked all the usual places (Spruce, Chief, etc) and can't find anything.
> Thanks, Don
>
>
________________________________________________________________________________
| From: | "Henry Trzeciakowski" <hammer408(at)comcast.net> |
| Subject: | Misc. Electrical Questions |
Bob:
I'm just about ready to begin my wiring in my 9A and I have a couple of
questions:
1) My load analysis is as follows: day VFR Cruise - Main Bus - 15.9
Edurance Bus - 8.65 Battery Bus - 1.0 for a total of 24.8 amps.....my
question is : should I use the drawing for "HEAVY ENDURANCE BUS", since
I'm going to draw over 7 amps and utilize the S704-1 relay and 10 amp
fuse for the battery bus?
2) I do plan on using an Avionics Master switch - I do know your
thoughts regarding not needing it, but ....... my questions is: the
Z-drawings depict 16 awg (6-8" run) from Main Bus to Diode and 16 awg
(6-8" run) from Diode to Endurance Bus - since I'm going to install the
AMS on the instrument panel, the run from the Diode to the panel will be
about 14-18"......what do you suggest for the size of wire and what is
the max lenght it should be.
3) Can I install the LR-3 Regulator and Battery Bus on the engine
side of the firewall....It seems to make sense for I wouldn't have to
run un-fused wires thru the firewall...
4) Can I run 14 awg wire to the Battery Bus from the + terminal of
the battery, instead of from the Master Battery Contactor? and
can I run 8 awg wire power supply to the Main Bus from the 60 amp
current limiter?
Thanks
Henry
________________________________________________________________________________
| From: | Dale Ellis <rv8builder(at)earthlink.net> |
| Subject: | Re: RE: Gilcrhist Electric |
I ordered a coax stripper via their web site and it was delivered via US mail while
I was at Sun'N'Fun last week sometime. Delivery time and price was as expected.
Note that I did not use ebay, etc to purchase this, I went directly to
their web site
No phone number was provided on the invoice, but the address is:
PO Box 10605
Bozeman, MT 59719
The web site is http://www.gilchrist-electric.com
The web site shows phone number as 409-586-6507.
Dale
-----Original Message-----
>From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
>Sent: Apr 10, 2008 12:48 PM
>To: aeroelectric-list(at)matronics.com
>Subject: AeroElectric-List: RE: Gilcrhist Electric
>
>
>
>><PLaurence@the-beach.net>
>>
>>
>>
>>-----Original Message-----
>>Bob and listers.
>>
>>Gilchrist Electric's phone numbers have been disconnected. Out of Business?
>>They clipped me for 14.00$.
>>
>>Payed through Google checkout. Can't seem to get anyone to answer my inquiry
>>at Gilchrist and Google.
>
> This has been reported to me by several builders. I've written the
> Chamber of Commerce in Bozeman and searched the 'net for any
> indication that the company has folded. No data has been
> forthcoming as of this writing. Gilchrist has also completely
> disappeared from Ebay in spite of the fact that their website
> is still up . . . and silent as to the fortunes of the company.
>
> I'm sorry to hear this. They gave me very good prices on
> lots of coax strippers during the time I was offering
> them from our website.
>
> Bob . . .
>
> ----------------------------------------)
> ( . . . a long habit of not thinking )
> ( a thing wrong, gives it a superficial )
> ( appearance of being right . . . )
> ( )
> ( -Thomas Paine 1776- )
> ----------------------------------------
>
>
________________________________________________________________________________
| Subject: | Re: Music Inputs |
| From: | "h&jeuropa" <butcher43(at)ATT.NET> |
Dustin,
I used a D sub crimper similar to the one Stein sells on Hi Density D sub pins
and it worked fine. The hi density pins are .050 in diameter (where the crimp
takes place) while the standard pins are .075. But my crimper contracts to about
.025 diameter. So I tried a couple and found the wire is nicely crimped.
You do have to be careful to position the pin correctly in the crimper as they
are different lengths. But to do a few crimps, a standard d sub crimper seems
to work OK.
Jim Butcher
Europa N241BW
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176694#176694
________________________________________________________________________________
| From: | Todd Heffley <list(at)toddheffley.com> |
| Subject: | Re: 90-Degree Adapter for Avionics Cooling Fan Hose |
The PVC 90 degree fitting at Lowes Aviation Supply fits right on.
Light yellow stuff that is cheaper than schedule 40....cant remember the name.
1 inch of pipe to make a bib.
Heat gun to soften it up and lock it onto the KX155 back plane.
Now lets see, how am I going to obtain a field approval on that....
todd
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: 90-Degree Adapter for Avionics Cooling Fan Hose |
No sweat, strictly a minor alteration!!
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/14/2008 8:10:58 A.M. Central Daylight Time,
list(at)toddheffley.com writes:
Heat gun to soften it up and lock it onto the KX155 back plane.
Now lets see, how am I going to obtain a field approval on that....
todd
**************It's Tax Time! Get tips, forms and advice on AOL Money &
Finance. (http://money.aol.com/tax?NCID=aolcmp00300000002850)
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Re: GARMIN GI-106A VS. MD200-306 CDI |
4/14/2008
Hello Bruce, You wrote: "Can you point me to the catalog locations or
suppliers
with the correct items numbers?"
I will try -- first a little basic information. The 430W and the SL30 both
put out and receive multiple signals to and from the 106A. So you need two
devices.
One device is a relatively simple push to activate switch on the instrument
panel which shifts the pilot's navigation choice from one source (430W) to
the other (SL30) or vice versa. This device should also have a light
indication on it to show which choice has been made.
The other device is remotely activated, more complicated, and it consists of
many relays and contact points that when activated by device number one
shifts all of the many signal paths between the 430W, the SL30, and the
106A.
There are multiple manufacturers and sources for both device one and device
two so one can shop around for their preference and purchase sources.
Here is a source for device one:
http://www.gulf-coast-avionics.com/list.asp?search_type=2&search_text=NAT
Here are some sources for device two:
http://www.sandia.aero/?q=SR64
http://www.trast-aero.com/eng/catalog/view.php?ModelId=401
These two sources are not intended to give you "ready to buy" information,
but rather to show you what kinds of devices you are looking for and some
possible items to purchase. It will take some leg work on your part to
discover the best devices for your use and the best sources to purchase them
from.
Perhaps other members on the list (Stein Bruch?) can also provide some more
specific choices / recommendations and sources.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
PS: I have some Excel spread sheets that I made up that show my equipment
and the rather complicated wiring interconnections. If you think that they
might be of use to you please email me direct and I will send them to you
as email attachments.
---------------------------------------------------------------------
Subject: Avionics-List: Re: GARMIN GI-106A VS. MD200-306 CDI
From: "Rv9APlane" <rv9aplane(at)gmail.com>
Hi OC,
I am new to the list and saw this today. I am planning the same equipment ,
i.e.,
a 430W, SL30, and 106A. I am not familiar with the items you mentioned
about
switching back and forth. Can you point me to the catalog locations or
suppliers
with the correct items numbers? I'm pretty weak on the electrical stuff
although I reading up on it now(Bob Nuckolls book). Thanks for your help.
--------
Bruce Peters
RV9A, Fuselage
Bakersfield, CA
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
>Oh my my. This is why people make fun of tech geeks and nerds, ha-ha.
Interesting . . . it seems that the same folks would also
make fun of neurosurgeons, master chefs and physicists.
Individuals who poke fun at the assemblage of simple-ideas
into useful inventions are themselves at-risk for not
enjoying the benefits that arise from understanding . . .
a kind of self imposed exile to ignorance that leaves
them dependent upon those who DO understand.
> Yes voltage, current and EMF are all magically intertwined.
Nothing magic about it. But the conditions under
which they interact are not consistent. For example,
just because there is voltage to be measured doesn't
automatically translate to a current flow. Similarly,
there are conditions where huge magnitudes of current
flow with zero impressed voltage.
>Even the magic of the hall effect sender puts out proportional
>volts to current.
Sort of . . . volts is proportional to the intensity
of a magnetic field. The magnetic field can come from
a variety of sources not the least of which is the
field surrounding a current carrying conductor.
>But you all are right, there are coils in those mechanical gauges.
>However a digital meter will read directly off a shunt? Huha? What?
>Doha! ha-ha.
Yes, the digital voltmeter takes advantage of the
voltage drop impressed across a shunt as a result
of current flow. The measurements obtained by this
method are independent of simple-ideas involving
magnetics.
>Bob your "VAM10_Interior_View link" is not working?
Yes, I corrected it in the posting that followed
a few minutes after the first. The working link
is . . .
http://www.aeroelectric.com/Pictures/Instruments/VAM40_Interior_View.jpg
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "F1 Rocket" <f1rocket(at)telus.net> |
| Subject: | 2 electrical questions - diode and intermittent failure |
The diode for the battery master, what are the specifications?
Twice now while flying my aircraft (over 100 hours with no problems), my
main power has flickered. Off and right back on. I just checked all the
wiring for the master, and the only thing I'm missing is the diode. Ground
was my obvious place to look, all OK, excellent ground for the master
switch.
My next choice is to change out the master solenoid. Any other ideas?
Rocket - dual alternator with single battery. Standard Z-13 wiring.
Thanks in advance,
Jeff
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: 2 electrical questions - diode and intermittent |
failure
>
>The diode for the battery master, what are the specifications?
>
>Twice now while flying my aircraft (over 100 hours with no problems), my
>main power has flickered. Off and right back on. I just checked all the
>wiring for the master, and the only thing I'm missing is the diode. Ground
>was my obvious place to look, all OK, excellent ground for the master
>switch.
>My next choice is to change out the master solenoid. Any other ideas?
>Rocket - dual alternator with single battery. Standard Z-13 wiring.
>
>Thanks in advance,
>Jeff
An intermittent battery master would not cause the
system to go down completely. In fact, it's possible
on some airplanes that an alternator will run reasonably
well without a battery . . . complete loss of the contactor
may not be immediately noticed.
If you're looking for loose wires, everything between
the bus and BOTH power sources (alternator and battery)
should be examined. Unless you soldered your terminals
on a good tug on the fat-wire terminals is in order.
I've seen wires installed with inadequate crimp tools
pull out of their respective terminals without a whole
lot of effort.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Questions on avionics |
4/15/2008
Hello Bruce, You wrote:
"1. What does it mean to "cage" an attitude indicator?"
Some attitude indicators have a mechanical means to lock the gyro gimbals so
that the gyro gimbals are held rigidly to the instrument case. This can
serve two functions:
A) It can save wear and tear on the gyro if you are going to do some
aerobatic manuevering and don't want the gyro to be moving around
extensively as it tries to always show the proper aircraft attitude.
B) If the gyro has tumbled and one wants to erect it again to a proper
attitude one can put the airplane in a level attitude, cage and then uncage
the gyro, and it will then start indicating properly a level attitude from
that new starting point.
"3. Is purchasing a separate encoder necessary?.....I see some avionics
vendors packaging
in a separate encoder but don't really understand why."
They are doing this because the altitude encoder in almost all of the EFIS
being sold to the amateur built community are not TSO'd and therefore do not
comply with FAR Sec 91.217 copied here:
"91.217: Data correspondence between automatically reported pressure
altitude data and the pilot's altitude reference.
No person may operate any automatic pressure altitude reporting equipment
associated with a radar beacon transponder-
(a) When deactivation of that equipment is directed by ATC;
(b) Unless, as installed, that equipment was tested and calibrated to
transmit altitude data corresponding within 125 feet (on a 95 percent
probability basis) of the indicated or calibrated datum of the altimeter
normally used to maintain flight altitude, with that altimeter referenced to
29.92 inches of mercury for altitudes from sea level to the maximum
operating altitude of the aircraft; or
(c) Unless the altimeters and digitizers in that equipment meet the
standards of TSO-C10b and TSO-C88, respectively."
So you can see that an altitude encoder in use must meet either be TSO'd or
comply with subparagraph (b) above.
Some people think that the encoder, altimeter, and transponder checks
required every two years by FAR Sections 91.411 and 91.413 meet the
requirements of subparagraph (b) above, but that is not the present position
of FAA HQ. They prescribe a more elaborate, almost impossible to accomplish
test.
So one solution to the problem created by having an EFIS with a non TSO'd
altitude encoder installed in your airplane is to install and use a separate
TSO'd altitude encoder.
If you want to read more on this subject go to the Matronic aeroelectric
list archive and search for 91.217.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
PS: Some EFIS manufacturers will claim that their altitude encoder "meets
TSO standards". Note that a claim of "meeting TSO standards" and being
actually TSO'd are not the same thing. Ironically some of these non TSO'd
altitude encoders are actually superior in performance and technology than
the standards required by the TSO. The EFIS manufacturers have chosen not to
obtain actual TSO approval for their altitude encoders because of the
expense and bureaucratic burden involved.
------------------------------------------------
> Subject: Avionics-List: Questions on avionics
> From: "Rv9APlane" <rv9aplane(at)gmail.com>
>
>
> Hi all,
> I have a couple of basic questions I don't understand well:
>
> 1. What does it mean to "cage" an attitude indicator? I've never flown a
> plane
> that has had this option but I see it on some I'm considering for my
> homebuilt.
>
> 2. I want a light IFR panel and have read some things about Mode S
> transponders.
> Is there any advantage to having one over a Mode C other than the TIS
> capability?
>
> 3. Is purchasing a separate encoder necessary? I was planning on putting
> a Blue
> Mountain EFIS One in my plane (please no negative comments as I'm already
> committed),
> a Garmin 430W with a GI-106A CDI, and a Garmin 327 transponder (pending
> the answer to number 2 above) in my plane. I see some avionics vendors
> packaging
> in a separate encoder but don't really understand why.
>
> Thanks for your help
>
> --------
> Bruce Peters
> RV9A, Fuselage
> Bakersfield, CA
________________________________________________________________________________
| From: | Ron Patterson <scc_ron(at)yahoo.com> |
| Subject: | Broken reception on my COMM |
My Comm works fine except when I receive a stronger signal from the local tower.
then the received transmission is broken and I can only hear about 1/2 the instructions.
Any ideas what may be causing this?
Ron
________________________________________________________________________________
| From: | <gmcjetpilot(at)yahoo.com> |
| Subject: | Re: Shunts (Nerds!) |
Bob, you're great, but lighten up. I am a Nerd. I have a
masters in engineering, and last time I mentioned that to
you, you attacked me and bashed engineering and
engineers from here to Sunday. I have lots of respect for
you, but that killed some of it, but I'm a nice forgiving
fellow. I have moved on.
As far as Nerds, I spend 5-6 years in undergrad and grad
school with an HP 41C hanging off my belt. I now dress
nicer and work out more, but I am still a Nerd at heart,
proudly.
As far as an AMP meter being a sensitive VOLT meter, it's
true. An AMP meter with out a shunt is a volt meter.
Basically we all are talking about D'Arsonval movement,
the way analog meters work, where current causes a EMF
(electromagnetic field) in a coil in an opposing direction to
permanent magnets, causing the needle to move. A
torsional (mechanical) spring or coil is calibrated to resist
the needle movement, thus reading a voltage (or current).
You don't need to be an engineer to understand how a
D'Arsonval movement works. I learned this when I was 12
years old, playing with my Radio Shack Science Fair
"160 in 1" electronic kit. However, now I can derive
Faraday equations (or Lenz) & explain the theoretical
physics with advanced math. That makes me a super
Nerd, proudly.
When I said magic Bob, I was being humorous, jocular,
whimsical, an attempt at being witty? Some people don't
need (or want) to know the details to wire a plane. I was
being causal, which is sometimes more productive when
addressing students, who might have anxieties about the
topic. It's just my style Bob, which obviously clashes with
yours.
I never taught "electronics" but I teach a lot of pilots, from
Student to Airline pilots, how the electrical system of a
Cessna to Boeing 747 works. Electrical systems are fun to
me and something I enjoy, not a place for argument or
politicking. It's just not a controversial subject to me. I just
want to help. I don't need to be perfect. As I have said Bob,
you have forgotten about the topic than I'll ever know, but
there is the off chance I know something you don't? I might
explain something in a way which gets through. That's all.
Cheers George the NERD!
PS thanks for the link. As a kid I broke many needle movement
taking them apart to see how they worked.
>From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
>Subject: Re: AeroElectric-List: Re: Shunts
>>Oh my my. This is why people make fun of tech geeks and nerds, ha-ha.
>Interesting . . . it seems that the same folks would also
>make fun of neurosurgeons, master chefs and physicists.
>Individuals who poke fun at the assemblage of simple-ideas
>into useful inventions are themselves at-risk for not
>enjoying the benefits that arise from understanding . . .
>a kind of self imposed exile to ignorance that leaves
>them dependent upon those who DO understand.
>> Yes voltage, current and EMF are all magically intertwined.
>Nothing magic about it. But the conditions under
>which they interact are not consistent. For example,
>just because there is voltage to be measured doesn't
>automatically translate to a current flow. Similarly,
>there are conditions where huge magnitudes of current
>flow with zero impressed voltage.
>>Even the magic of the hall effect sender puts out proportional
>>volts to current.
>Sort of . . . volts is proportional to the intensity
>of a magnetic field. The magnetic field can come from
>a variety of sources not the least of which is the
>field surrounding a current carrying conductor.
>>But you all are right, there are coils in those mechanical gauges.
>>However a digital meter will read directly off a shunt? Huha? What?
>>Doha! ha-ha.
>Yes, the digital voltmeter takes advantage of the
>voltage drop impressed across a shunt as a result
>of current flow. The measurements obtained by this
>method are independent of simple-ideas involving
>magnetics.
>>Bob your "VAM10_Interior_View link" is not working?
>Yes, I corrected it in the posting that followed
>a few minutes after the first. The working link
>is . . .
http://www.aeroelectric.com/Pictures/Instruments/VAM40_Interior_View.jpg
>Bob . . .
between 0000-00-00 and 9999-99-99
________________________________________________________________________________
| From: | "F1 Rocket" <f1rocket(at)telus.net> |
| Subject: | 2 electrical questions - diode and intermittent |
failure
Hi Bob,
Thanks for the usual quick reply.
Just for my brain... If the alternator had a loose wire, wouldn't the
battery still supply the required power? I didn't think I would see the
power drop out if I lost the alternator (I was hoping I would get the low
voltage alarm so I could start the back up alternator).
Jeff
-----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: April 14, 2008 9:05 PM
Subject: Re: AeroElectric-List: 2 electrical questions - diode and
intermittent failure
>
>The diode for the battery master, what are the specifications?
>
>Twice now while flying my aircraft (over 100 hours with no problems), my
>main power has flickered. Off and right back on. I just checked all the
>wiring for the master, and the only thing I'm missing is the diode. Ground
>was my obvious place to look, all OK, excellent ground for the master
>switch.
>My next choice is to change out the master solenoid. Any other ideas?
>Rocket - dual alternator with single battery. Standard Z-13 wiring.
>
>Thanks in advance,
>Jeff
An intermittent battery master would not cause the
system to go down completely. In fact, it's possible
on some airplanes that an alternator will run reasonably
well without a battery . . . complete loss of the contactor
may not be immediately noticed.
If you're looking for loose wires, everything between
the bus and BOTH power sources (alternator and battery)
should be examined. Unless you soldered your terminals
on a good tug on the fat-wire terminals is in order.
I've seen wires installed with inadequate crimp tools
pull out of their respective terminals without a whole
lot of effort.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Broken reception on my COMM |
>My Comm works fine except when I receive a stronger signal from the local
>tower. then the received transmission is broken and I can only hear about
>1/2 the instructions. Any ideas what may be causing this?
>
>Ron
I presume that communication with the tower while
airborne is not a problem and that you've identified
signal strength as the apparent variable. Your receiver
may be suffering from an overload condition that's beyond
its ability to accommodate.
A receiver designer's sorta wet dream is to have the
squelch break at around 0.2 microvolts signal and produce a
readable if somewhat noisy output at 0.5 microvolts
at the antenna. When I was working in the two-way radio
business these were the benchmarks for refurbishing
and aligning a receiver.
A device with this performance level may be hard pressed
to also accept and demodulate a signal of hundreds of
microvolts. The automatic gain system within the receiver
may not have sufficient dynamic range to handle the larger
signal in close proximity to a ground based (read high power)
transmitter.
Do you carry a hand held? Perhaps ground ops is an excellent
time to pre-flight this very useful back up. This may not
be an automatic solution . . . hand helds tend to be a cut
or two below panel mounted or base station receivers and
it may be similarly afflicted with the effects of strong
signal overload . . . but it's the simplest solution and
worth trying.
If push comes to shove, you can install the formation
flying attenuator described at:
http://www.aeroelectric.com/articles/Attenuator/Formation_Flying_Attenuator_2.pdf
See also pictures at:
http://www.aeroelectric.com/articles/Attenuator/
Note that this particular design is capable of handling
the output of a 2 watt transmitter continuously. It's
fine for transmitters of 4-6 watt range but don't carry
on long winded conversations.
With this switch in the "attenuate" position, both your
incoming and outgoing signals are considerably reduced
to avoid overloading the receiver in your cockpit and
in the other aircraft's cockpit. The ground station will
have no problem hearing you either.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | MartinErni(at)aol.com |
| Subject: | Re: Broken reception on my COMM |
Jerry,
Read about this problem and Bob's reply. Does it sound familiar? May be
this will give us a fix.
E
In a message dated 4/15/2008 9:52:13 A.M. Eastern Daylight Time,
nuckolls.bob(at)cox.net writes:
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>My Comm works fine except when I receive a stronger signal from the local
>tower. then the received transmission is broken and I can only hear about
>1/2 the instructions. Any ideas what may be causing this?
>
>Ron
I presume that communication with the tower while
airborne is not a problem and that you've identified
signal strength as the apparent variable. Your receiver
may be suffering from an overload condition that's beyond
its ability to accommodate.
A receiver designer's sorta wet dream is to have the
squelch break at around 0.2 microvolts signal and produce a
readable if somewhat noisy output at 0.5 microvolts
at the antenna. When I was working in the two-way radio
business these were the benchmarks for refurbishing
and aligning a receiver.
A device with this performance level may be hard pressed
to also accept and demodulate a signal of hundreds of
microvolts. The automatic gain system within the receiver
may not have sufficient dynamic range to handle the larger
signal in close proximity to a ground based (read high power)
transmitter.
Do you carry a hand held? Perhaps ground ops is an excellent
time to pre-flight this very useful back up. This may not
be an automatic solution . . . hand helds tend to be a cut
or two below panel mounted or base station receivers and
it may be similarly afflicted with the effects of strong
signal overload . . . but it's the simplest solution and
worth trying.
If push comes to shove, you can install the formation
flying attenuator described at:
http://www.aeroelectric.com/articles/Attenuator/Formation_Flying_Attenuator_2.
pdf
See also pictures at:
http://www.aeroelectric.com/articles/Attenuator/
Note that this particular design is capable of handling
the output of a 2 watt transmitter continuously. It's
fine for transmitters of 4-6 watt range but don't carry
on long winded conversations.
With this switch in the "attenuate" position, both your
incoming and outgoing signals are considerably reduced
to avoid overloading the receiver in your cockpit and
in the other aircraft's cockpit. The ground station will
have no problem hearing you either.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
**************It's Tax Time! Get tips, forms and advice on AOL Money &
Finance. (http://money.aol.com/tax?NCID=aolcmp00300000002850)
________________________________________________________________________________
| From: | Jim Piavis <jpiavis(at)microsoft.com> |
| Subject: | Tail Nav Light Ground |
I'm wiring up the tail nav/ strobe light in the lower fiberglass rudder fai
ring for an RV-7. Is there any reason I can't tie the nav light ground to t
he strobe ground? For the tail light, this seems to be the easiest option b
ut wasn't sure about the voltage running through the strobe. It's either th
at or run a wire into the aft fuselage to a local ground.
Jim
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Bits of aviation history . . . |
See:
http://tinyurl.com/39cbwo
http://www.rbogash.com/B314.html
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Tail Nav Light Ground |
>I m wiring up the tail nav/ strobe light in the lower fiberglass rudder
>fairing for an RV-7. Is there any reason I can t tie the nav light ground
>to the strobe ground? For the tail light, this seems to be the easiest
>option but wasn t sure about the voltage running through the strobe. It s
>either that or run a wire into the aft fuselage to a local ground.
You don't want to cause an unbalance of currents
to flow inside the twisted trio of strobe wires.
The physics that make this wire an effective constraint
on coupling of noise depends on integrity of combination
of balanced currents and shielding.
The separate ground wire is called for.
Bob . . .
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Questions on avionics |
Good Morning OC,
Nice answer to the question asked, but may a I add a bit?
If you intend to do aerobatics and intend to cage the gyros to avoid wear,
it is best to shut of the air first so that the gyro is not spinning while it
is locked up. While being caged will keep it from banging the stops, the
bearings will be exposed to abnormal wear by the gyro being restrained. If the
air is turned of after the gyro is already spun up, a good gyro will take about
thirty minutes to get stopped. Best to shut off the air before the engine is
started.
There is no real good solution, only methods of mitigation.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/15/2008 7:47:34 A.M. Central Daylight Time,
bakerocb(at)cox.net writes:
Hello Bruce, You wrote:
"1. What does it mean to "cage" an attitude indicator?"
Some attitude indicators have a mechanical means to lock the gyro gimbals so
that the gyro gimbals are held rigidly to the instrument case. This can
serve two functions:
A) It can save wear and tear on the gyro if you are going to do some
aerobatic maneuvering and don't want the gyro to be moving around
extensively as it tries to always show the proper aircraft attitude.
B) If the gyro has tumbled and one wants to erect it again to a proper
attitude one can put the airplane in a level attitude, cage and then uncage
the gyro, and it will then start indicating properly a level attitude from
that new starting point.
**************It's Tax Time! Get tips, forms and advice on AOL Money &
Finance. (http://money.aol.com/tax?NCID=aolcmp00300000002850)
________________________________________________________________________________
| From: | MauleDriver <MauleDriver(at)nc.rr.com> |
| Subject: | Re: Tail Nav Light Ground |
I just faced the same issue. I chose to run a separate ground from the
Adel clamp holding the rudder cable.
It also took a bit more effort than expected to get a single lug #4
platenut in there to hold the Whelan. But it worked well.
Jim Piavis wrote:
>
> I'm wiring up the tail nav/ strobe light in the lower fiberglass
> rudder fairing for an RV-7. Is there any reason I can't tie the nav
> light ground to the strobe ground? For the tail light, this seems to
> be the easiest option but wasn't sure about the voltage running
> through the strobe. It's either that or run a wire into the aft
> fuselage to a local ground.
>
>
>
> Jim
>
> *
>
>
> *
________________________________________________________________________________
| From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
| Subject: | Questions on avionics |
Really the best way to do aerobatics is to fit a glass EFIS...I regularly (
like every flight) wring out my RV and the Dynon scratches its head sometim
es but returns to normal like clockwork. Same for the TT autopilot.
I noticed that Kathy Hirtz does her airshow routines in her Wolf Pitts and
has a Dynon D180 installed..And there is not a more radical aerobatic machi
ne out there.
Its about time the mechanical gyros went the way of the Dodo...As long as y
our airplane is experimental of course.
Frank
________________________________
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectr
ic-list-server(at)matronics.com] On Behalf Of BobsV35B(at)aol.com
Sent: Tuesday, April 15, 2008 9:29 AM
Subject: Re: AeroElectric-List: Questions on avionics
Good Morning OC,
Nice answer to the question asked, but may a I add a bit?
If you intend to do aerobatics and intend to cage the gyros to avoid wear,
it is best to shut of the air first so that the gyro is not spinning while
it is locked up. While being caged will keep it from banging the stops, the
bearings will be exposed to abnormal wear by the gyro being restrained. I
f the air is turned of after the gyro is already spun up, a good gyro will
take about thirty minutes to get stopped. Best to shut off the air before t
he engine is started.
There is no real good solution, only methods of mitigation.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/15/2008 7:47:34 A.M. Central Daylight Time, bakerocb@c
ox.net writes:
Hello Bruce, You wrote:
"1. What does it mean to "cage" an attitude indicator?"
Some attitude indicators have a mechanical means to lock the gyro gimbals s
o
that the gyro gimbals are held rigidly to the instrument case. This can
serve two functions:
A) It can save wear and tear on the gyro if you are going to do some
aerobatic maneuvering and don't want the gyro to be moving around
extensively as it tries to always show the proper aircraft attitude.
B) If the gyro has tumbled and one wants to erect it again to a proper
attitude one can put the airplane in a level attitude, cage and then uncage
the gyro, and it will then start indicating properly a level attitude from
that new starting point.
________________________________
It's Tax Time! Get tips, forms and advice on AOL Money & Finance<http://mon
ey.aol.com/tax?NCID=aolcmp00300000002850>.
________________________________________________________________________________
| From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
| Subject: | 2 electrical questions - diode and intermittent |
failure
Something that was a real "Doh!" moment was that I realised I had painted the alternator
bracket...I.e where the ground path was for the alternator...The resistance
of the paint caused a whole bunch of noise that would do little annoyances
like shut the IFR GPS off while on an instrument approach...of course it
would take 10 seconds or so to reset..and then do it again..Not very pleasant!
Just a thought...I.e the connection of the alternator to the engine block is a
vital connection.
Frank
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of F1 Rocket
Sent: Monday, April 14, 2008 3:21 PM
Subject: AeroElectric-List: 2 electrical questions - diode and intermittent failure
-->
The diode for the battery master, what are the specifications?
Twice now while flying my aircraft (over 100 hours with no problems), my main power
has flickered. Off and right back on. I just checked all the wiring for
the master, and the only thing I'm missing is the diode. Ground was my obvious
place to look, all OK, excellent ground for the master switch.
My next choice is to change out the master solenoid. Any other ideas?
Rocket - dual alternator with single battery. Standard Z-13 wiring.
Thanks in advance,
Jeff
________________________________________________________________________________
| From: | MartinErni(at)aol.com |
| Subject: | Re: 2 electrical questions - diode and intermittent |
failure
Anodized alternator brackets can cause the same problems. Guess how I know.
a message dated 4/15/2008 1:27:39 P.M. Eastern Daylight Time,
frank.hinde(at)hp.com writes:
--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)"
Something that was a real "Doh!" moment was that I realised I had painted
the alternator bracket...I.e where the ground path was for the alternator...The
resistance of the paint caused a whole bunch of noise that would do little
annoyances like shut the IFR GPS off while on an instrument approach...of
course it would take 10 seconds or so to reset..and then do it again..Not very
pleasant!
Just a thought...I.e the connection of the alternator to the engine block is
a vital connection.
Frank
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of F1 Rocket
Sent: Monday, April 14, 2008 3:21 PM
Subject: AeroElectric-List: 2 electrical questions - diode and intermittent
failure
-->
The diode for the battery master, what are the specifications?
Twice now while flying my aircraft (over 100 hours with no problems), my
main power has flickered. Off and right back on. I just checked all the wiring
for the master, and the only thing I'm missing is the diode. Ground was my
obvious place to look, all OK, excellent ground for the master switch.
My next choice is to change out the master solenoid. Any other ideas?
Rocket - dual alternator with single battery. Standard Z-13 wiring.
Thanks in advance,
Jeff
**************It's Tax Time! Get tips, forms and advice on AOL Money &
Finance. (http://money.aol.com/tax?NCID=aolcmp00300000002850)
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Questions on avionics |
Good Afternoon Frank,
Absolutely and totally agree!
The problem is that the FAA puts so many hurdles in the way that by the time
the stuff gets approved, the cost is way above what normal folks can afford.
Right now, only home builders have any chance of going with modern
equipment.
I do realize that most FAA folks are just as enthusiastic aviators as are
the rest of us, but they are hamstrung with rules that are forced on them by the
Bureaucracy and that Bureaucracy is driven by the Congress critters who do
nothing for us at all.
All they care about is having someone to blame when anything goes wrong.
I recently had the pleasure of flying some twenty-four hours in a Legend Cub
that was equipped with the Dynon 180. I certainly did not learn how to use
all of it's many capabilities, but what I saw, was great.
I have been following Jim Younkin's very rapid development of flight
instruments and autopilots. I love his attitude toward the FAA, but it doesn't
help
we who fly primarily certified aircraft.
Unless someone who is willing to argue with the FAA manages to steal some of
his ideas and get the FAA approval for us to use that much better stuff, we
are stuck with 1920s technology.
Had the FAA been in charge in 1920 we would not yet have mechanical gyros,
let alone anything better!
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/15/2008 12:22:40 P.M. Central Daylight Time,
frank.hinde(at)hp.com writes:
Really the best way to do aerobatics is to fit a glass EFIS...I regularly
(like every flight) wring out my RV and the Dynon scratches its head sometimes
but returns to normal like clockwork. Same for the TT autopilot.
I noticed that Kathy Hirtz does her airshow routines in her Wolf Pitts and
has a Dynon D180 installed..And there is not a more radical aerobatic machine
out there.
Its about time the mechanical gyros went the way of the Dodo...As long as
your airplane is experimental of course.
Frank
**************It's Tax Time! Get tips, forms and advice on AOL Money &
Finance. (http://money.aol.com/tax?NCID=aolcmp00300000002850)
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: 2 electrical questions - diode and intermittent |
failure
MartinErni(at)aol.com wrote:
> Anodized alternator brackets can cause the same problems. Guess how I know.
>
>
Yeah, but in that case it looks DAMN good while it's not working 8*).
________________________________________________________________________________
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
| Subject: | Questions on avionics |
Bob.
Aspen Avionics http://www.aspenavionics.com/ recently received the TSO and
the AML STC for their glass PFD.
$6,000 + install for a VFR unit; $10,000 + install for an IFR unit. Not
really cheap, but not as pricey as Garmin or Avidyne. So you guys flying TC
aircraft can get some of the toys without totally busting the bank.
And no more spinning gyros!
Thanks!
Bill Denton
bdenton(at)bdenton.com
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
BobsV35B(at)aol.com
Sent: Tuesday, April 15, 2008 12:56 PM
Subject: Re: AeroElectric-List: Questions on avionics
Good Afternoon Frank,
Absolutely and totally agree!
The problem is that the FAA puts so many hurdles in the way that by the time
the stuff gets approved, the cost is way above what normal folks can afford.
Right now, only home builders have any chance of going with modern
equipment.
I do realize that most FAA folks are just as enthusiastic aviators as are
the rest of us, but they are hamstrung with rules that are forced on them by
the Bureaucracy and that Bureaucracy is driven by the Congress critters who
do nothing for us at all.
All they care about is having someone to blame when anything goes wrong.
I recently had the pleasure of flying some twenty-four hours in a Legend Cub
that was equipped with the Dynon 180. I certainly did not learn how to use
all of it's many capabilities, but what I saw, was great.
I have been following Jim Younkin's very rapid development of flight
instruments and autopilots. I love his attitude toward the FAA, but it
doesn't help we who fly primarily certified aircraft.
Unless someone who is willing to argue with the FAA manages to steal some of
his ideas and get the FAA approval for us to use that much better stuff, we
are stuck with 1920s technology.
Had the FAA been in charge in 1920 we would not yet have mechanical gyros,
let alone anything better!
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/15/2008 12:22:40 P.M. Central Daylight Time,
frank.hinde(at)hp.com writes:
Really the best way to do aerobatics is to fit a glass EFIS...I regularly
(like every flight) wring out my RV and the Dynon scratches its head
sometimes but returns to normal like clockwork. Same for the TT autopilot.
I noticed that Kathy Hirtz does her airshow routines in her Wolf Pitts and
has a Dynon D180 installed..And there is not a more radical aerobatic
machine out there.
Its about time the mechanical gyros went the way of the Dodo...As long as
your airplane is experimental of course.
Frank
_____
It's Tax Time! Get tips, forms and advice on AOL
<http://money.aol.com/tax?NCID=aolcmp00300000002850> Money & Finance.
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Questions on avionics |
Good Afternoon Bill,
It's getting there!
I do know that they are now saying the entire year's production is already
spoken for.
Last person I spoke to said they figure the installation they ordered would
be at least twenty grand installed. Better than a Garmin, but still a lot of
money. If it was an automotive device, produced in China, and used on a Toyo
ta
it would be fifty bucks!
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/15/2008 1:29:02 P.M. Central Daylight Time,
bdenton(at)bdenton.com writes:
Bob
Aspen Avionics http://www.aspenavionics.com/ recently received the TSO and
the AML STC for their glass PFD.
$6,000 + install for a VFR unit; $10,000 + install for an IFR unit. Not
really cheap, but not as pricey as Garmin or Avidyne. So you guys flying TC
aircraft can get some of the toys without totally busting the bank.
And no more spinning gyros!
Thanks!
Bill Denton
bdenton(at)bdenton.com
**************It's Tax Time! Get tips, forms and advice on AOL Money &
Finance. (http://money.aol.com/tax?NCID=aolcmp00300000002850)
________________________________________________________________________________
| From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
| Subject: | Questions on avionics |
Yes I feel for the certified guys...The last IFR proficiency ride i took my
instrument student friend and he kept babbling something about "what about
the precession"....I said "We're not in a precession, we're flying by ours
elves!"
Nice to hear from you again Bob....And you were right, learning IFR in a fa
st airplane is not hard at all...learning in one that happens to be aerobat
ic its a bit of a handful though..:)
Frank RV7a
________________________________
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectr
ic-list-server(at)matronics.com] On Behalf Of BobsV35B(at)aol.com
Sent: Tuesday, April 15, 2008 10:56 AM
Subject: Re: AeroElectric-List: Questions on avionics
Good Afternoon Frank,
Absolutely and totally agree!
The problem is that the FAA puts so many hurdles in the way that by the tim
e the stuff gets approved, the cost is way above what normal folks can affo
rd.
Right now, only home builders have any chance of going with modern equipmen
t.
I do realize that most FAA folks are just as enthusiastic aviators as are t
he rest of us, but they are hamstrung with rules that are forced on them by
the Bureaucracy and that Bureaucracy is driven by the Congress critters w
ho do nothing for us at all.
All they care about is having someone to blame when anything goes wrong.
I recently had the pleasure of flying some twenty-four hours in a Legend Cu
b that was equipped with the Dynon 180. I certainly did not learn how to us
e all of it's many capabilities, but what I saw, was great.
I have been following Jim Younkin's very rapid development of flight instru
ments and autopilots. I love his attitude toward the FAA, but it doesn't he
lp we who fly primarily certified aircraft.
Unless someone who is willing to argue with the FAA manages to steal some o
f his ideas and get the FAA approval for us to use that much better stuff,
we are stuck with 1920s technology.
Had the FAA been in charge in 1920 we would not yet have mechanical gyros,
let alone anything better!
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/15/2008 12:22:40 P.M. Central Daylight Time, frank.hin
de(at)hp.com writes:
Really the best way to do aerobatics is to fit a glass EFIS...I regularly (
like every flight) wring out my RV and the Dynon scratches its head sometim
es but returns to normal like clockwork. Same for the TT autopilot.
I noticed that Kathy Hirtz does her airshow routines in her Wolf Pitts and
has a Dynon D180 installed..And there is not a more radical aerobatic machi
ne out there.
Its about time the mechanical gyros went the way of the Dodo...As long as y
our airplane is experimental of course.
Frank
________________________________
It's Tax Time! Get tips, forms and advice on AOL Money & Finance<http://mon
ey.aol.com/tax?NCID=aolcmp00300000002850>.
________________________________________________________________________________
| From: | "Dustin Paulson" <dustinp(at)hughes.net> |
| Subject: | Re: Music Inputs |
Thanks Jim.
I guess it's certainly worth a try, and see if they will pass the pull
test, but I sure wouldn't want to be in hard IFR, and have my MP3 player
all of a sudden be unhearable because of a poor crimp. ~( ;- )
Dustin,
I used a D sub crimper similar to the one Stein sells on Hi
Density D sub pins
and it worked fine. The hi density pins are .050 in diameter
(where the crimp
takes place) while the standard pins are .075. But my crimper
contracts to about
.025 diameter. So I tried a couple and found the wire is nicely
crimped.
You do have to be careful to position the pin correctly in the
crimper as they
are different lengths. But to do a few crimps, a standard d sub
crimper seems
to work OK.
Jim Butcher
Europa N241BW
________________________________________________________________________________
| From: | "Jeffrey W. Skiba" <jskiba(at)icosa.net> |
| Subject: | Ray Allen Trim servos |
ALL,
I am looking for a simple way to reduce the speed of my Ray Allen Trim
servos.
What I need to know is the best way to Slow the speed of the servos down. I
have seen the ray Allen servo speed controller however I would need 2 of
them at $45 each seems a bit pricey, and I was hoping the group has a cost
effective solution.
Could one just use a resistor ? I am guessing the Ray Allen controller is a
PWM maybe some one knows of a cheaper version ?
Any direction would be appreciated
Jeff.
________________________________________________________________________________
| From: | Sheldon Olesen <saolesen(at)sirentel.net> |
| Subject: | Re: Ray Allen Trim servos |
On Apr 15, 2008, at 9:07 PM, Jeffrey W. Skiba wrote:
> ALL,
>
> I am looking for a simple way to reduce the speed of my Ray Allen
> Trim servos.
> What I need to know is the best way to Slow the speed of the servos
> down. I have seen the ray Allen servo speed controller however I
> would need 2 of them at $45 each seems a bit pricey, and I was
> hoping the group has a cost effective solution.
>
> Could one just use a resistor ? I am guessing the Ray Allen
> controller is a PWM maybe some one knows of a cheaper version ?
>
> Any direction would be appreciated
> Jeff.
>
>
Jeff,
I have 2 speed controllers and 2 relays that I removed to install a
Safety trim system. They were installed but the plane has never
flown. Make me an offer I can't refuse.
Sheldon Olesen
________________________________________________________________________________
| From: | "mike humphrey" <mike109g6(at)insideconnect.net> |
| Subject: | Re: Ray Allen Trim servos |
Jeff,
Simple installation. Very effective, and can be adjusted via a pot to
get it exactly how you want the speed to be. I've got two, brand new in
the box, never used, that I will sell you. I have one mounted on the
elevator trim, bought two more it seems while in a 'buying frenzy'.
I'll sell both for $60 including shipping to lower 48. Email me direct
if interested: mike109g6(at)insideconnect.net
Mike H 9A/8A
----- Original Message -----
From: Jeffrey W. Skiba
To: aeroelectric-list(at)matronics.com
Sent: Tuesday, April 15, 2008 10:07 PM
Subject: AeroElectric-List: Ray Allen Trim servos
ALL,
I am looking for a simple way to reduce the speed of my Ray Allen Trim
servos.
What I need to know is the best way to Slow the speed of the servos
down. I have seen the ray Allen servo speed controller however I would
need 2 of them at $45 each seems a bit pricey, and I was hoping the
group has a cost effective solution.
Could one just use a resistor ? I am guessing the Ray Allen controller
is a PWM maybe some one knows of a cheaper version ?
Any direction would be appreciated
Jeff.
________________________________________________________________________________
| Subject: | Re: Questions on avionics |
| From: | "rampil" <ira.rampil(at)gmail.com> |
Re: TSO and altimetry sources
There is no requirement for TSO in owner built aircraft. As I said
previously, there is only a performance requirement.
Part 23 is a separate issue.
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177151#177151
________________________________________________________________________________
| From: | Jeff Page <jpx(at)Qenesis.com> |
I was surprised to find halves of grommets lying on the floor of my
hangar the other day. In January, they were installed in the leading
edge ribs. It has been too cold here in Toronto to do much work on my
plane since then.
As far as I can tell, the holes in the aluminum ribs shrunk from the
cold and cut the grommets in half. I am glad I found this out before
pulling all the wires through !
The holes were drilled a hair smaller than the grommets, which fit
nicely without bunching up. The holes were carefully deburred and I
can rotate my finger in the holes without feeling a sharp edge.
The grommets I purchased from Spaenaur rather than the local hardware
store. They are specd as material: SBR, hardness: 60 durometer +/-5.
Are these grommets the wrong material ?
Should there be slack around the grommet when fitted in the hole ?
Some other problem I haven't thought of ?
Thanks,
Jeff Page
Dream Aircraft Tundra #10
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
Jeff Page wrote:
>
> I was surprised to find halves of grommets lying on the floor of my
> hangar the other day. In January, they were installed in the leading
> edge ribs. It has been too cold here in Toronto to do much work on my
> plane since then.
>
> As far as I can tell, the holes in the aluminum ribs shrunk from the
> cold and cut the grommets in half. I am glad I found this out before
> pulling all the wires through !
>
> The holes were drilled a hair smaller than the grommets, which fit
> nicely without bunching up. The holes were carefully deburred and I
> can rotate my finger in the holes without feeling a sharp edge.
>
> The grommets I purchased from Spaenaur rather than the local hardware
> store. They are specd as material: SBR, hardness: 60 durometer +/-5.
>
> Are these grommets the wrong material ?
>
That would be my guess. If it was too cold to work on the plane and you
believe the aluminum shrunk, then the grommet were possibly as brittle
as glass. One of the techniques for manufacturing rubber bushings is to
freeze them and then machine them like metal. They got nice and brittle
(but probably didn't shrink much), and then the aluminum closed in on
them. Probably happened several times.
Try keeping a 60W lightbulb turned on in the plane.
________________________________________________________________________________
| From: | "Bill Boyd" <sportav8r(at)gmail.com> |
60W light bulb isn't going to help much at altitude. It gets COLD up
there. I'd suggest a re-do with looser holes or different material. Just
my $.02
-Bill B
On Wed, Apr 16, 2008 at 11:27 AM, Ernest Christley
wrote:
> echristley(at)nc.rr.com>
>
> Jeff Page wrote:
>
> >
> > I was surprised to find halves of grommets lying on the floor of my
> > hangar the other day. In January, they were installed in the leading edge
> > ribs. It has been too cold here in Toronto to do much work on my plane
> > since then.
> >
> > As far as I can tell, the holes in the aluminum ribs shrunk from the
> > cold and cut the grommets in half. I am glad I found this out before
> > pulling all the wires through !
> >
> > The holes were drilled a hair smaller than the grommets, which fit
> > nicely without bunching up. The holes were carefully deburred and I can
> > rotate my finger in the holes without feeling a sharp edge.
> >
> > The grommets I purchased from Spaenaur rather than the local hardware
> > store. They are specd as material: SBR, hardness: 60 durometer +/-5.
> >
> > Are these grommets the wrong material ?
> >
> > That would be my guess. If it was too cold to work on the plane and
> you believe the aluminum shrunk, then the grommet were possibly as brittle
> as glass. One of the techniques for manufacturing rubber bushings is to
> freeze them and then machine them like metal. They got nice and brittle
> (but probably didn't shrink much), and then the aluminum closed in on them.
> Probably happened several times.
>
> Try keeping a 60W lightbulb turned on in the plane.
>
>
________________________________________________________________________________
| From: | "Danny Smith" <dsmit132(at)bellsouth.net> |
| Subject: | Voltage Drop in DM15-14 Dimmer |
I have the DM15-14 dimmer with only a Garmin GMA-340, TT ADI and a 3 ft LED
strip (.086amp) attached to it.
When I turned on the LED strip it didn't seem very bright so I checked the
voltage and found that with an
input to the dimmer of 12.7 V the output was only 9.7 V. Is a 3 V drop to be
expected or is the dimmer
module defective?
Danny
________________________________________________________________________________
While not disputing that the grommets failed, I must question your
explanation. The coefficient of thermal expansion for aluminum alloy 3003
(a common sheet alloy) is 12.9 microinch/inch deg F, so doing the math for a
1 inch diameter hole and a temperature change from a really hot 100 deg F
day for installation and a really cold minus 50 deg F day during the winter
you get a worst case diameter change of slightly less than .002 inch. A
half inch diameter hole would change less than .001 inch for the same
temperature change.
Installing the grommets into an undersize hole, thus stressing the grommet,
is probably the culprit, not contraction alone.
Best regards,
Rob Housman
Irvine, CA
Europa XS Tri-Gear
A070
Airframe complete
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jeff Page
Sent: Wednesday, April 16, 2008 7:53 AM
Subject: AeroElectric-List: Grommets
I was surprised to find halves of grommets lying on the floor of my
hangar the other day. In January, they were installed in the leading
edge ribs. It has been too cold here in Toronto to do much work on my
plane since then.
As far as I can tell, the holes in the aluminum ribs shrunk from the
cold and cut the grommets in half. I am glad I found this out before
pulling all the wires through !
The holes were drilled a hair smaller than the grommets, which fit
nicely without bunching up. The holes were carefully deburred and I
can rotate my finger in the holes without feeling a sharp edge.
The grommets I purchased from Spaenaur rather than the local hardware
store. They are specd as material: SBR, hardness: 60 durometer +/-5.
Are these grommets the wrong material ?
Should there be slack around the grommet when fitted in the hole ?
Some other problem I haven't thought of ?
Thanks,
Jeff Page
Dream Aircraft Tundra #10
________________________________________________________________________________
| From: | <Flagstone(at)cox.net> |
Jeff:
Your finding has me concerned. Could you provide the following details:
1 Grommet Dimensions or Spaenaur part #:
Inside Diameter
Groove Diameter
Outside Diameter
Groove Width
Overall Thickness
2 Hole Diameter
3 Rib thickness
Were the wires in conduit? If so what was the outside diameter of the
conduit.
Do you have a pic of the installed grommet and the split grommet you can
post?
Thanks
Mark
----- Original Message -----
From: "Jeff Page" <jpx(at)Qenesis.com>
Sent: Wednesday, April 16, 2008 7:52 AM
Subject: AeroElectric-List: Grommets
>
> I was surprised to find halves of grommets lying on the floor of my
> hangar the other day. In January, they were installed in the leading
> edge ribs. It has been too cold here in Toronto to do much work on my
> plane since then.
>
> As far as I can tell, the holes in the aluminum ribs shrunk from the cold
> and cut the grommets in half. I am glad I found this out before pulling
> all the wires through !
>
> The holes were drilled a hair smaller than the grommets, which fit nicely
> without bunching up. The holes were carefully deburred and I can rotate
> my finger in the holes without feeling a sharp edge.
>
> The grommets I purchased from Spaenaur rather than the local hardware
> store. They are specd as material: SBR, hardness: 60 durometer +/-5.
>
> Are these grommets the wrong material ?
>
> Should there be slack around the grommet when fitted in the hole ?
>
> Some other problem I haven't thought of ?
>
> Thanks,
>
> Jeff Page
> Dream Aircraft Tundra #10
>
>
>
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
Bill Boyd wrote:
> 60W light bulb isn't going to help much at altitude. It gets COLD up
> there. I'd suggest a re-do with looser holes or different material. Just
> my $.02
>
>
OK. A 120W bulb.....and a really long drop cord. 8*)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Voltage Drop in DM15-14 Dimmer |
>
>
>I have the DM15-14 dimmer with only a Garmin GMA-340, TT ADI and a 3 ft LED
>strip (.086amp) attached to it.
>When I turned on the LED strip it didn't seem very bright so I checked the
>voltage and found that with an
>input to the dimmer of 12.7 V the output was only 9.7 V. Is a 3 V drop to be
>expected or is the dimmer
>module defective?
It's probably okay. The regulator used in those dimmers is
one of the LM317 series devices. You can get the data sheet
at:
http://cache.national.com/ds/LM/LM117.pdf
the figure on page 6 labeled "Dropout Votlage"
tells us that the minimum input-output differential
can be as high as 2.0 volts depending on load.
I had a number of folks question the voltage
drop at max intensity settings . . . if it's
a valid concern, there are other devices that
offer reduced overhead maximums.
When I designed those dimmers, the goal was
(1) provide control of virtually any size illumination
load by means of a small, panel friendly control
potentiometer and (2) offer good voltage regulation
such that bus voltage perturbations didn't show
up in the panel lighting. An ancillary consideration
was that 98+ percent of dimmer operations were at
very low output settings . . . on the order of 4-6
volts.
The duration of flight time where visibility
of the illuminated objects would be enhanced
by raising the dimmer from say 11 to 14 volts
is a very few minutes during the day-night
transition. Hence, limiting maximum output to
2 volts or so below bus voltage was not a big
deal.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Emond" <d_emond(at)mweb.co.za> |
| Subject: | Ground Power - Z31A |
Bob
Please can you confirm the correct procedure for using the ground power on
Z31a architecture.
Is it imperative to first switch on the "ground power" switch, before
switching on the master switch?
Would I just switch ground power off, once the aircraft has started?
What would happen if ground power switch was inadvertantly left on for an
indefinite period, or turned on whilst the aircraft engine was running?
Your assistance as always is appreciated.
Dave Emond
RV10
________________________________________________________________________________
| Subject: | Re: Rear Mounted Batteries - more questions |
| From: | "n277dl" <dljinia(at)yahoo.com> |
Bob and list,
Using the previously attached document as reference...
Assumptions... rear mounted batteries. Main Bat Cntctr, Aux Bat cntctr and Xfeed
Cntctr all mounted in rear beside the batteries. 2awg ground wire to fwd
central gnd bus attached to the engine via stud through firewall. XFEED cnctr
closed for starting. 2AWG wire from the same side of XFEED cntctr that the main
bat cntctr is connected to starter cntctr.
Questions.... Can I then run appropriate sized wire (tbd) from the same side of
the starter cntctr as the 2awg wire is attached to the main pwr bus?
If so, I also assume I would run appropriate sized wire ~8-10 awg (but not the
heavy 2awg) from aux bat side of the XFEED to the Aux bus and use same wire to
from the aux alt (prob 8 amp b&C alternator).
Hope this makes sense. Really just trying to understand if I can only run two
fat wires from the batteries to the firewall if I want to ground at the firewall
or need to pull the extra "hot fat wire".
thanks. Doug
--------
Doug
"Fools" are always more creative than process people and will always
find ways to ruin a perfectly good set of processes.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177275#177275
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Ground Power - Z31A |
>
>Bob
>
>Please can you confirm the correct procedure for using the ground power on
>Z31a architecture.
>
>Is it imperative to first switch on the "ground power" switch, before
>switching on the master switch?
No. The ground power may be turned on at any time in the
starting sequence without regard to damage to the system.
The ground power circuits as depicted are reverse polarity
and ov protected . . .
>Would I just switch ground power off, once the aircraft has started?
Yes.
>What would happen if ground power switch was inadvertantly left on for an
>indefinite period, or turned on whilst the aircraft engine was running?
No big deal. IF the ground power source voltage was set
higher than your ship's regulator, your alternator
would not come on line and pick up system loads as long
as the ground power was connected. If you're getting a
start from a battery cart - as ship's systems came
alive, your ship's alternator would begin to charge/
re-charge ALL batteries in the system . . . including those
in a still connected ground power cart.
If you're using external power from an engine driven or
AC mains powered cart, then would would expect the external
voltage source to be set at "battery charging" voltage
levels (14.2 or 28.5). In this case, you could turn on
ground power long before closing the master switch and
let ground power replenish you ship's battery. After
15 minutes or so, your ship's battery may well contain
sufficient snort to start your engine and ground power
could be disconnected for the start an subsequent
pre-flight. If the ground power is a battery cart,
then no charging of the ship's battery can take place
and you're obligated to use ground power to get the
engine started. After starting, you'd want to turn
ground power off so that ALL of your ship's alternator
output was being used to replenish stored energy in
the ship's battery.
In cold weather, you may wish to use ground power
as a routine assist for getting the engine
started even if your battery is in good shape.
Aside from the possibility of too much ground power
voltage and/or reversed polarity, there are no risks to
your airplane's systems that warrant concern. Making
ground power managed from the pilot's seat
puts you in control of this resource for the purpose
of addressing the task at hand.
It's an energy management problem with solutions
determined by equipment available, condition of
your battery and immediate goals. I recall reading
a story many moons ago where a pilot used his ground
power jumper cables to get his car started using
his airplane's battery after returning from a trip
and finding the car battery was not up to the task.
>Your assistance as always is appreciated.
Pleased to be of service sir!
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Rear Mounted Batteries - more questions |
>
>Bob and list,
> Using the previously attached document as reference...
>
>Assumptions... rear mounted batteries. Main Bat Cntctr, Aux Bat cntctr
>and Xfeed Cntctr all mounted in rear beside the batteries.
Hmmmm . . . normally we'd like to see the cross-feed contactor
mounted on the firewall. This provides nice fat-wire terminals
from both batteries to serve as distribution points for the
two batteries in addressing their respective tasks.
> 2awg ground wire to fwd central gnd bus attached to the engine via stud
> through firewall. XFEED cnctr closed for starting. 2AWG wire from the
> same side of XFEED cntctr that the main bat cntctr is connected to
> starter cntctr.
Okay . . .
>Questions.... Can I then run appropriate sized wire (tbd) from the same
>side of the starter cntctr as the 2awg wire is attached to the main pwr bus?
Yes. If your cross-feed contactor were up front
then the battery distribution tie point would be
on the cross-feed contactor. With the configuration
you've described, then the starter contactor becomes
the tie point.
>If so, I also assume I would run appropriate sized wire ~8-10 awg (but not
>the heavy 2awg) from aux bat side of the XFEED to the Aux bus and use same
>wire to from the aux alt (prob 8 amp b&C alternator).
Oops . . . sounds like you're describing a Z-14
architecture using an SD-8 on the aux side. Not
recommended due to aux battery contactor loads being
such a significant portion of the SD-8's output.
Suggest a Z-13 architecture is more appropriate to
maximizing the capabilities of the SD-8.
>Hope this makes sense. Really just trying to understand if I can only run
>two fat wires from the batteries to the firewall if I want to ground at
>the firewall or need to pull the extra "hot fat wire".
Let's talk about your architecture and choices
of hardware to fill the various slots. What
shortcomings do you perceive with a Z-13 architecture
that drives you toward dual batteries?
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | "Chubby" wires and fuseblocks |
>Comments/Questions: I dont' undestand how to connect large current loads
>to FASTON fuse blocks.
>
>Max wire into FASTON seems to be #10
>
>Fuses up 30A are sold by B&C
>
>Most #10 wire is not rated for 30A.
I don't know of any #10 wire that is not rated for
30A in airplanes.
>What am I missing?
>
I don't recommend any fuses beyond 14AWG/15A be used
in the fuse blocks. What systems are you wiring
that demand the use of larger wire/fuses?
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
>Comments/Questions: Hi Bob,
>
>Re: S700-2-10 switch
>
>What is the current rating for this switch?
The S700 series switches are Carling G-series devices.
The data sheet for this line of products may be reviewed
at:
http://www.aeroelectric.com/Mfgr_Data/Switches/Carling_G-series.pdf
Note that these are rated at up to 20A in 120VAC systems.
In the article at:
http://aeroelectric.com/articles/Switch_Ratings.pdf
we explore the simple ideas behind current ratings
and service life of switches as installed in various
working environments.
>I would like to use this switch to turn on rotating beacons (12 amps) and
>strobe lights (11 amps) using the circuit in figure 11-18 (page 11-19) in
>the 11th edition of your book. The B&C catalog lists the rating as '15VAC
>maximum'. How does this rating apply to a 14 volt system?
>My application would run 23 amps through the switch. Will the switch
>handle this load?
Yes, you'll probably get a satisfactory service life
using the S700-2-10 for this application. But I'm curious
as to where you got these current values. I'm also curious
as to why you have a combination of strobes and rotating
beacons on the same airplane.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | Jeff Page <jpx(at)Qenesis.com> |
Mark,
Here is the link to the grommet info:
http://www.spaenaur.ca/pdf/sectionJ/J69.pdf
The grommets are not all the same size, but most are 315-263. So the
groove diameter is 7/16 and I would have drilled 27/64" holes.
I think the ribs are 6061-T6 32 thou.
Unfortunately, I have a bad cold, so I won't be able to visit the
hangar to take photos. If you held a grommet in your fingers and
sliced it vertically with a dull knife, tearing as well as cutting,
that's what they look like.
I pushed the grommets in when it was about freezing temperature, but
they were still quite pliable. They were not difficult to install
using just my fingers. It didn't run any wire or conduit in them,
just left them there. The frame of the wing is rivetted, but the
skins are not on it yet. It is just sitting on the workbench.
As long as the SBR material is considered aviation quality, I expect I
just need larger holes.
Jeff
> From: <Flagstone(at)cox.net>
> Subject: Re: AeroElectric-List: Grommets
>
> Your finding has me concerned. Could you provide the following details:
>
> 1 Grommet Dimensions or Spaenaur part #:
> Inside Diameter
> Groove Diameter
> Outside Diameter
> Groove Width
> Overall Thickness
>
> 2 Hole Diameter
>
> 3 Rib thickness
>
> Were the wires in conduit? If so what was the outside diameter of the
> conduit.
>
> Do you have a pic of the installed grommet and the split grommet you can
> post?
________________________________________________________________________________
| From: | "Bubblehead" <jdalman2000(at)yahoo.com> |
rob(at)hyperion-ef.com wrote:
> While not disputing that the grommets failed, I must question your
> explanation. The coefficient of thermal expansion for aluminum alloy 3003
> (a common sheet alloy) is 12.9 microinch/inch deg F, so doing the math for a
> 1 inch diameter hole and a temperature change from a really hot 100 deg F
> day for installation and a really cold minus 50 deg F day during the winter
> you get a worst case diameter change of slightly less than .002 inch. A
> half inch diameter hole would change less than .001 inch for the same
> temperature change.
>
> Installing the grommets into an undersize hole, thus stressing the grommet,
> is probably the culprit, not contraction alone.
>
>
> Best regards,
>
> Rob Housman
> Irvine, CA
> Europa XS Tri-Gear
> A070
> Airframe complete
>
> --
Rob - I think you're using the coefficient for the aluminum and then computing
the change based on the size of the hole. The change in hole size is because of
the change in the aluminum size. 1" or 1/2" hole doesn't matter - only the amount
of aluminum around the hole!
Actually, as the aluminum cools wouldn't it contract, making the hole bigger? The
temperature would have to rise so the aluminum expands to make the hole smaller.
My opinion is the bushings got brittle and maybe had flaws or residual stresses
that made them break. I doubt change in hole diameter had anything to do with
it.
John
--------
John Dalman
Elburn, IL
RV-8 N247TD
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177406#177406
________________________________________________________________________________
| From: | <Flagstone(at)cox.net> |
Jeff:
That's all I need to work with. Thanks
Hope you feel better
Mark
----- Original Message -----
From: "Jeff Page" <jpx(at)Qenesis.com>
Sent: Thursday, April 17, 2008 6:14 AM
Subject: AeroElectric-List: Re: Grommets
>
> Mark,
>
> Here is the link to the grommet info:
> http://www.spaenaur.ca/pdf/sectionJ/J69.pdf
> The grommets are not all the same size, but most are 315-263. So the
> groove diameter is 7/16 and I would have drilled 27/64" holes.
> I think the ribs are 6061-T6 32 thou.
> Unfortunately, I have a bad cold, so I won't be able to visit the
> hangar to take photos. If you held a grommet in your fingers and
> sliced it vertically with a dull knife, tearing as well as cutting,
> that's what they look like.
> I pushed the grommets in when it was about freezing temperature, but
> they were still quite pliable. They were not difficult to install
> using just my fingers. It didn't run any wire or conduit in them,
> just left them there. The frame of the wing is rivetted, but the
> skins are not on it yet. It is just sitting on the workbench.
>
> As long as the SBR material is considered aviation quality, I expect I
> just need larger holes.
>
> Jeff
>
>> From: <Flagstone(at)cox.net>
>> Subject: Re: AeroElectric-List: Grommets
>>
>> Your finding has me concerned. Could you provide the following details:
>>
>> 1 Grommet Dimensions or Spaenaur part #:
>> Inside Diameter
>> Groove Diameter
>> Outside Diameter
>> Groove Width
>> Overall Thickness
>>
>> 2 Hole Diameter
>>
>> 3 Rib thickness
>>
>> Were the wires in conduit? If so what was the outside diameter of the
>> conduit.
>>
>> Do you have a pic of the installed grommet and the split grommet you can
>> post?
>
>
>
>
>
>
>
________________________________________________________________________________
"Bubblehead" wrote:
>
>
> Rob - I think you're using the coefficient for the aluminum and then computing
the change based on the size of the hole. The change in hole size is because
of the change in the aluminum size. 1" or 1/2" hole doesn't matter - only the
amount of aluminum around the hole!
>
> Actually, as the aluminum cools wouldn't it contract, making the hole bigger?
The temperature would have to rise so the aluminum expands to make the hole smaller.
>
> My opinion is the bushings got brittle and maybe had flaws or residual stresses
that made them break. I doubt change in hole diameter had anything to do with
it.
>
> John
>
> --------
> John Dalman
> Elburn, IL
> RV-8 N247TD
>
>
Hi John,
When you're looking at the dimensional change in the material, you have
to look at the overall dimensions of the item. Say you have a piece of
aluminum 10 inches X 10 inches with a 1 inch dia hole in the center.
If a drop in temperature causes the material to shrink 0.001 inch per
inch (just to pick a number), the new dimensions will be 10 thousandths
less or 9.99 X 9.99 and the inside hole will be .999 inches in dia.
The size of the internal hole will be the same as if the material was
still there.
Bob W.
--
N93BD - Rotary Powered BD-4 - http://www.bob-white.com
3.8 Hours Total Time and holding
Cables for your rotary installation - http://roblinstores.com/cables/
________________________________________________________________________________
| From: | "RALPH HOOVER" <hooverra(at)verizon.net> |
Jeff,
Just a guess but exposure to solvents could breakdown SBR. I cannot
imagine that hole size alone is the issue.
http://www.alliedrubber.com/Gasket/SBRRubber.cfm.htm
"When exposed to petroleum derivatives, the performance of this rubber is
inferior to many other synthetics. Red SBR rubber is popular for use as a
gasket in low pressure applications such as washers and gaskets for the
heating and plumbing trades. Black SBR is commonly used for abrasion
conditions such as skirtboard and chute lining."
Ralph & Laura Hoover
RV7A N527LR
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jeff Page
Sent: Wednesday, April 16, 2008 10:53 AM
Subject: AeroElectric-List: Grommets
I was surprised to find halves of grommets lying on the floor of my
hangar the other day. In January, they were installed in the leading
edge ribs. It has been too cold here in Toronto to do much work on my
plane since then.
As far as I can tell, the holes in the aluminum ribs shrunk from the
cold and cut the grommets in half. I am glad I found this out before
pulling all the wires through !
The holes were drilled a hair smaller than the grommets, which fit
nicely without bunching up. The holes were carefully deburred and I
can rotate my finger in the holes without feeling a sharp edge.
The grommets I purchased from Spaenaur rather than the local hardware
store. They are specd as material: SBR, hardness: 60 durometer +/-5.
Are these grommets the wrong material ?
Should there be slack around the grommet when fitted in the hole ?
Some other problem I haven't thought of ?
Thanks,
Jeff Page
Dream Aircraft Tundra #10
________________________________________________________________________________
I'm glad to hear that I wasn't the only student that did not fall asleep in
freshman physics lecture.
Best regards,
Rob Housman
Irvine, CA
Europa XS Tri-Gear
A070
Airframe complete
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob White
Sent: Thursday, April 17, 2008 7:51 AM
Subject: Re: AeroElectric-List: Re: Grommets
"Bubblehead" wrote:
>
>
> Rob - I think you're using the coefficient for the aluminum and then
computing the change based on the size of the hole. The change in hole size
is because of the change in the aluminum size. 1" or 1/2" hole doesn't
matter - only the amount of aluminum around the hole!
>
> Actually, as the aluminum cools wouldn't it contract, making the hole
bigger? The temperature would have to rise so the aluminum expands to make
the hole smaller.
>
> My opinion is the bushings got brittle and maybe had flaws or residual
stresses that made them break. I doubt change in hole diameter had anything
to do with it.
>
> John
>
> --------
> John Dalman
> Elburn, IL
> RV-8 N247TD
>
>
Hi John,
When you're looking at the dimensional change in the material, you have
to look at the overall dimensions of the item. Say you have a piece of
aluminum 10 inches X 10 inches with a 1 inch dia hole in the center.
If a drop in temperature causes the material to shrink 0.001 inch per
inch (just to pick a number), the new dimensions will be 10 thousandths
less or 9.99 X 9.99 and the inside hole will be .999 inches in dia.
The size of the internal hole will be the same as if the material was
still there.
Bob W.
--
N93BD - Rotary Powered BD-4 - http://www.bob-white.com
3.8 Hours Total Time and holding
Cables for your rotary installation - http://roblinstores.com/cables/
________________________________________________________________________________
| From: | "Bryan" <bhcishere(at)ca.rr.com> |
Heat makes the hole bigger. Haven't you ever had to remove a stubborn bolt?
That is done with a torch to make the hole bigger.
Bryan
----- Original Message -----
From: "Rob Housman" <rob@hyperion-ef.com>
Sent: Thursday, April 17, 2008 1:35 PM
Subject: RE: AeroElectric-List: Re: Grommets
> <rob@hyperion-ef.com>
>
> I'm glad to hear that I wasn't the only student that did not fall asleep
> in
> freshman physics lecture.
>
>
> Best regards,
>
> Rob Housman
> Irvine, CA
> Europa XS Tri-Gear
> A070
> Airframe complete
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob
> White
> Sent: Thursday, April 17, 2008 7:51 AM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Re: Grommets
>
>
> "Bubblehead" wrote:
>
>
>>
>>
>> Rob - I think you're using the coefficient for the aluminum and then
> computing the change based on the size of the hole. The change in hole
> size
> is because of the change in the aluminum size. 1" or 1/2" hole doesn't
> matter - only the amount of aluminum around the hole!
>>
>> Actually, as the aluminum cools wouldn't it contract, making the hole
> bigger? The temperature would have to rise so the aluminum expands to make
> the hole smaller.
>>
>> My opinion is the bushings got brittle and maybe had flaws or residual
> stresses that made them break. I doubt change in hole diameter had
> anything
> to do with it.
>>
>> John
>>
>> --------
>> John Dalman
>> Elburn, IL
>> RV-8 N247TD
>>
>>
> Hi John,
>
> When you're looking at the dimensional change in the material, you have
> to look at the overall dimensions of the item. Say you have a piece of
> aluminum 10 inches X 10 inches with a 1 inch dia hole in the center.
> If a drop in temperature causes the material to shrink 0.001 inch per
> inch (just to pick a number), the new dimensions will be 10 thousandths
> less or 9.99 X 9.99 and the inside hole will be .999 inches in dia.
> The size of the internal hole will be the same as if the material was
> still there.
>
>
> Bob W.
>
>
> --
> N93BD - Rotary Powered BD-4 - http://www.bob-white.com
> 3.8 Hours Total Time and holding
> Cables for your rotary installation - http://roblinstores.com/cables/
>
>
> --
> Checked by AVG.
> 9:00 AM
>
>
________________________________________________________________________________
| From: | "raymondj" <raymondj(at)frontiernet.net> |
| Subject: | Thermal expansion (was Grommets) |
Listers,
The link below provides info. applicable to the conversation.
http://hyperphysics.phy-astr.gsu.edu/Hbase/thermo/thexp2.html#c1
Raymond Julian
Kettle River, MN
"Hope for the best,
but prepare for the worst."
________________________________________________________________________________
| Subject: | Re: Rear Mounted Batteries - more questions |
| From: | "n277dl" <dljinia(at)yahoo.com> |
Bob,
Thanks for the response and heres some more details....
building a rv10, dual grt hx, 430w, sl30, tt - ap, lycoming io540 - one lightspeed
ignition and one mag. Will have basic airspeed round gauges for backup...
ie groudspeed, vsi, altimeter and an electric gyro attitude indicator. Have
similar systems in RV7A except dynon not grt, no sl30 and all both mags.
Why two batteries...primarily rumblings on those with efis to the need to have
the two batteries in starting to keep from resetting the boot-up operation of
the efis's during engine startup (honestly, unverified by me). Adding an extra
battery is an insignificant expense (relatively speaking). Having two batteries
would make me more comfortable with dual electronic ignition in the future.
I won't start that way as engine already ordered and configured but it's much
easier to plumb for future than redo later.
>
> Hmmmm . . . normally we'd like to see the cross-feed contactor
> mounted on the firewall. This provides nice fat-wire terminals
> from both batteries to serve as distribution points for the
> two batteries in addressing their respective tasks.
>
In a previous post on the original thread you stated....
>
> Quote:
>
> The crossfeed contactor, starter contactor and current limiter
> block can be mounted within inches of each other and "wired" with
> flat strap like the pictures found in this directory . . .
>
> http://www.aeroelectric.com/Pictures/Wiring_Technique/
>
> The short straps are much easier to fabricate and install than
> very short hunks of fat wire with terminals.
>
> Bob . . .
>
So I'm a little confused. Maybe I took this one out of context and was specifically
directed at firewall mounted batteries.
I've actually already ran the two 2awg fat wires to the front where I could mount
the xfeed contactor but then found the above post and thought maybe it should
only be one.
I'm on the road this week but will review the z13 tomorrow night. Maybe all I
need and don't need the extra complexity.
Thanks again,
Doug
--------
Doug
"Fools" are always more creative than process people and will always
find ways to ruin a perfectly good set of processes.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177495#177495
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
| Subject: | A Bit of Help, Please |
I am installing Whelen LED taxi/recognition lights.
Each one draws 0.9 amps.
I am using an DPDT on-off-on switch to operate them. One position for
steady on, one for flashing. I want to use only one switch instead of two.
I'm using Eric Jones' wig wag flasher for the recognition mode.
For the flash switch selection, I've wired one side with leads from the
flasher module that activate the flash.
For the steady on switch selection, I've wired power through the other side
of the switch.
When in flash mode, to keep power from going back through the wires and
causing the lights to stay on constantly, I've added zener diodes.
The diodes are Radio Shack 12v INT4742A. The package says the
characteristics are current = 21mA and max power dissipation = 1.0W.
I've tested the lights with the diodes in the power wires for 45 minutes
without a problem.
My question is - Are these diodes sufficient for long term use with lights
drawing 0.9 Amps?
Thanks in advance,
Stan Sutterfield
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | Joemotis(at)aol.com |
| Subject: | Re: A Bit of Help, Please |
Buy the right ones rated for your load and sleep at night.
If you cannot afford it, contact me off list and I will mail you a couple :)
Joe Motis
No archivos amigo
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Questions on avionics |
4/17/2008
Hello Ira,
1) You wrote: "There is no requirement for TSO in owner built aircraft."**
2) FAR SEC 91.217 Says:
"Data correspondence between automatically reported pressure
altitude data and the pilot's altitude reference.
No person may operate any automatic pressure altitude reporting equipment
associated with a radar beacon transponder-
(a) When deactivation of that equipment is directed by ATC;
(b) Unless, as installed, that equipment was tested and calibrated to
transmit altitude data corresponding within 125 feet (on a 95 percent
probability basis) of the indicated or calibrated datum of the altimeter
normally used to maintain flight altitude, with that altimeter referenced to
29.92 inches of mercury for altitudes from sea level to the maximum
operating altitude of the aircraft; or
(c) Unless the altimeters and digitizers in that equipment meet the
standards of TSO-C10b and TSO-C88, respectively."
3) Please explain, with specific valid reference, why the phrase "No person
may ..." seen above would not apply to a person flying an amateur built
experimental aircraft.
4) You are correct that there are alternatives to using TSO'd equipment,
when such equipment is specifically required by a regulation, provided that
you can prove to the FAA's satisfaction that your alternative equipment is
acceptable to the FAA. Here is how you go about doing that:
FAR Sec. 21.609 "Approval for deviation.
(a) Each manufacturer who requests approval to deviate from any performance
standard of a TSO shall show that the standards from which a deviation is
requested are compensated for by factors or design features providing an
equivalent level of safety.
(b) The request for approval to deviate, together with all pertinent data,
must be submitted to the Manager of the Aircraft Certification Office for
the geographic area in which the manufacturer is located. If the article is
manufactured in another country, the request for approval to deviate,
together with all pertinent data, must be submitted through the civil
aviation authority in that country to the FAA."
Obtaining an approval for deviation is not a trivial task and none of the
manufacturers of non TSO'd altitude encoders contained in their EFIS units
have done so to my knowledge.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
**PS: This statement is also not correct when it comes to the ELT installed,
if one is required by FAR Sec 91.207, in an amateur built experimental
aircraft.
-----------------------------------------------------------------
Subject: Re: Questions on avionics
From: "rampil" <ira.rampil(at)gmail.com>
Re: TSO and altimetry sources
There is no requirement for TSO in owner built aircraft. As I said
previously, there is only a performance requirement.
Part 23 is a separate issue.
--------
Ira N224XS
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | pinout for Softcom ATC-P intercom?? |
Can anyone point me to an installation manual (or just the pin IDs of
the dB25) for a Softcom ATC-P intercom?
I thought there was a collection of installation diagrams on the
Aeroelectric site, but I've been unable to locate it.
Thanks,
Charlie
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: A Bit of Help, Please |
>I am installing Whelen LED taxi/recognition lights.
>Each one draws 0.9 amps.
>I am using an DPDT on-off-on switch to operate them. One position for
>steady on, one for flashing. I want to use only one switch instead of two.
>I'm using Eric Jones' wig wag flasher for the recognition mode.
>For the flash switch selection, I've wired one side with leads from the
>flasher module that activate the flash.
>For the steady on switch selection, I've wired power through the other
>side of the switch.
>When in flash mode, to keep power from going back through the wires and
>causing the lights to stay on constantly, I've added zener diodes.
>The diodes are Radio Shack 12v INT4742A. The package says the
>characteristics are current = 21mA and max power dissipation = 1.0W.
>I've tested the lights with the diodes in the power wires for 45 minutes
>without a problem.
>My question is - Are these diodes sufficient for long term use with lights
>drawing 0.9 Amps?
>Thanks in advance,
>Stan Sutterfield
It's not clear as to why you selected Zener diodes for this
task. Zeners are for voltage regulation . . . and it seems
that the task you're describing uses the diodes to prevent
reverse current flow under some conditions. Now, if you've
used a 1N4742 zener in the forward biased mode to replace
a simple rectifier diode, then the current ratings stated
for zener operation do not apply. A 1N4742 forward biased
zener is probably good for about an amp . . . but in the
reverse direction, the condition that you want the current
to be zero, the 12 zener mode of operation will kick in and
it will cause the difference between your 14v system and the
12v rating of the zener to be impressed across parts of the
system that you want to be completely 'cold'.
See:
http://www.aeroelectric.com/Pictures/Misc/RS_Diodes.jpg
The smallest diode suited to the task would be the
1N4001 offered as RS catalog number 276-1101. However,
higher voltage ratings don't hurt a thing so any of the
1N400-series devices could be used.
My personal preference for mechanical robustness are
the 1N5400-series, 3 amp devices. Again, having a part
that is electrically "too big" isn't a factor for your
application. These diodes are about 3x the size
and have more robust bodies and leadwires. These are
the diodes shown in this picture:
http://www.aeroelectric.com/Pictures/Contactors/s701-2.jpg
When we were selling this assembly, the fatter diodes
were selected for ease of assembly and robustness.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Transponder for sale (mode S) |
Ernest Christley wrote:
>
>
> Michael Pereira wrote:
>>
>>
>> I don't really understand this. The cost of avionics is because of the
>> low volume and the liability costs. Implementing Linux isn't going to
>> cut the costs more than 20 bucks on a device. This is a huge deduction
>> for something like a wifi router. It's noise if you're talking about a
>> device like a garmin 430.
>>
>
> The point wasn't that the OLPC uses Linux. The point was that the
> technology to implement a self configuring mesh network is both cheap
> and widespread. The point was that the people in charge think of
> $3,000 as "low cost", while the same task is being done for <$200.
>
> I realize that Garmin has to make a few pennies. I'm also an
> engineer, and I like to eat, too. But I don't expect the government
> to legislate that everyone by a Cisco C6500 to use the internet. That
> sort of equipment is just way overkill for the job. To say that the
> industry should pursue a technology direction that forces everyone to
> buy expensive equipment, when the same job can be performed...neigh,
> is being performed...by much cheaper equipment so that someone can
> make some money is a broken window argument.
>
> Part of the problem is the low volume, as you claim. And so they
> propose a system that will perpetuate the need to use low volume
> devices? All that would be required to implement the design goals
> that I've seen is a white-box GPS, the innards of a PalmVx, and a
> medium strength transceiver. The software is trivial, considering the
> number of examples with open source available (ie, the hard part is
> done already). There's nothing in the mix that would push a
> marginally successful product into the $3,000 range.
>
> I think most people involved with aircraft are jaded to the point they
> truly believe everything should cost thousands. You have not, because
> you ask not.
>
I'm running a bit behind on emails.
Hi Earnest,
You're right, of course. Anyone notice the activity on the RV list & the
VAF forum about APRS? Take a look at Sam Buchanan's installation.
http://home.hiwaay.net/~sbuc/journal/tracker.htm
The whole setup is only a couple hundred bucks; for a few hundred more,
you could receive & display the info directly in the cockpit. These
things do basically everything that ADS-B does, plus a little more. The
low wattage xmitter (all you need) would fit in the base of a
streamlined antenna, with just power & serial data lines coming in the
cockpit. In fact, a dedicated antenna on the top of the plane could
contain the GPS rcvr & need nothing but power.
Charlie
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: Questions on avionics |
bakerocb(at)cox.net wrote:
>
> 4/17/2008
>
> Hello Ira,
>
> 1) You wrote: "There is no requirement for TSO in owner built
> aircraft."**
>
> 2) FAR SEC 91.217 Says:
>
> "Data correspondence between automatically reported pressure
> altitude data and the pilot's altitude reference.
>
> No person may operate any automatic pressure altitude reporting equipment
> associated with a radar beacon transponder-
>
> (a) When deactivation of that equipment is directed by ATC;
>
> (b) Unless, as installed, that equipment was tested and calibrated to
> transmit altitude data corresponding within 125 feet (on a 95 percent
> probability basis) of the indicated or calibrated datum of the altimeter
> normally used to maintain flight altitude, with that altimeter
> referenced to
> 29.92 inches of mercury for altitudes from sea level to the maximum
> operating altitude of the aircraft; or
>
> (c) Unless the altimeters and digitizers in that equipment meet the
> standards of TSO-C10b and TSO-C88, respectively."
>
> 3) Please explain, with specific valid reference, why the phrase "No
> person may ..." seen above would not apply to a person flying an
> amateur built experimental aircraft.
I don't understand why you think what he said is wrong.
No person may operate any automatic pressure altitude reporting
equipment ...Unless.... that equipment was tested and calibrated...;
or...that equipment meet the standards of TSO-C10b and TSO-C88
There's an OR statement there. One, the other, or both can be true, and
the statement is still true (I'm a Software Engineer by training, so I
took a special class just for that sort of reasoning 8*)
--
http://www.ronpaultimeline.com
________________________________________________________________________________
| From: | "Mike" <mlas(at)cox.net> |
| Subject: | Questions on avionics |
I would argue that you are not looking for a deviation to the TSO you
are looking to comply with the standard of the TSO without a formal
proof.
Mike
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
bakerocb(at)cox.net
Sent: Thursday, April 17, 2008 6:51 PM
ira.rampil(at)gmail.com
Subject: AeroElectric-List: Questions on avionics
4/17/2008
Hello Ira,
1) You wrote: "There is no requirement for TSO in owner built
aircraft."**
2) FAR SEC 91.217 Says:
"Data correspondence between automatically reported pressure
altitude data and the pilot's altitude reference.
No person may operate any automatic pressure altitude reporting
equipment
associated with a radar beacon transponder-
(a) When deactivation of that equipment is directed by ATC;
(b) Unless, as installed, that equipment was tested and calibrated to
transmit altitude data corresponding within 125 feet (on a 95 percent
probability basis) of the indicated or calibrated datum of the altimeter
normally used to maintain flight altitude, with that altimeter
referenced to
29.92 inches of mercury for altitudes from sea level to the maximum
operating altitude of the aircraft; or
(c) Unless the altimeters and digitizers in that equipment meet the
standards of TSO-C10b and TSO-C88, respectively."
3) Please explain, with specific valid reference, why the phrase "No
person
may ..." seen above would not apply to a person flying an amateur built
experimental aircraft.
4) You are correct that there are alternatives to using TSO'd equipment,
when such equipment is specifically required by a regulation, provided
that
you can prove to the FAA's satisfaction that your alternative equipment
is
acceptable to the FAA. Here is how you go about doing that:
FAR Sec. 21.609 "Approval for deviation.
(a) Each manufacturer who requests approval to deviate from any
performance
standard of a TSO shall show that the standards from which a deviation
is
requested are compensated for by factors or design features providing an
equivalent level of safety.
(b) The request for approval to deviate, together with all pertinent
data,
must be submitted to the Manager of the Aircraft Certification Office
for
the geographic area in which the manufacturer is located. If the article
is
manufactured in another country, the request for approval to deviate,
together with all pertinent data, must be submitted through the civil
aviation authority in that country to the FAA."
Obtaining an approval for deviation is not a trivial task and none of
the
manufacturers of non TSO'd altitude encoders contained in their EFIS
units
have done so to my knowledge.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
**PS: This statement is also not correct when it comes to the ELT
installed,
if one is required by FAR Sec 91.207, in an amateur built experimental
aircraft.
-----------------------------------------------------------------
Subject: Re: Questions on avionics
From: "rampil" <ira.rampil(at)gmail.com>
Re: TSO and altimetry sources
There is no requirement for TSO in owner built aircraft. As I said
previously, there is only a performance requirement.
Part 23 is a separate issue.
--------
Ira N224XS
10/2/2007 11:10 AM
10/2/2007 11:10 AM
________________________________________________________________________________
| From: | "Mike" <mlas(at)cox.net> |
| Subject: | Questions on avionics |
Read the regulation. It says that the 'encoder' must meet the TSO
standards. It doesn't say that it must be TSO'd. That is a subtle
legal difference.
Mike
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Ernest Christley
Sent: Thursday, April 17, 2008 7:51 PM
Subject: Re: AeroElectric-List: Questions on avionics
bakerocb(at)cox.net wrote:
>
> 4/17/2008
>
> Hello Ira,
>
> 1) You wrote: "There is no requirement for TSO in owner built
> aircraft."**
>
> 2) FAR SEC 91.217 Says:
>
> "Data correspondence between automatically reported pressure
> altitude data and the pilot's altitude reference.
>
> No person may operate any automatic pressure altitude reporting
equipment
> associated with a radar beacon transponder-
>
> (a) When deactivation of that equipment is directed by ATC;
>
> (b) Unless, as installed, that equipment was tested and calibrated to
> transmit altitude data corresponding within 125 feet (on a 95 percent
> probability basis) of the indicated or calibrated datum of the
altimeter
> normally used to maintain flight altitude, with that altimeter
> referenced to
> 29.92 inches of mercury for altitudes from sea level to the maximum
> operating altitude of the aircraft; or
>
> (c) Unless the altimeters and digitizers in that equipment meet the
> standards of TSO-C10b and TSO-C88, respectively."
>
> 3) Please explain, with specific valid reference, why the phrase "No
> person may ..." seen above would not apply to a person flying an
> amateur built experimental aircraft.
I don't understand why you think what he said is wrong.
No person may operate any automatic pressure altitude reporting
equipment ...Unless.... that equipment was tested and calibrated...;
or...that equipment meet the standards of TSO-C10b and TSO-C88
There's an OR statement there. One, the other, or both can be true, and
the statement is still true (I'm a Software Engineer by training, so I
took a special class just for that sort of reasoning 8*)
--
http://www.ronpaultimeline.com
10/2/2007 11:10 AM
10/2/2007 11:10 AM
________________________________________________________________________________
| From: | Kevin Horton <khorton01(at)rogers.com> |
| Subject: | Re: Questions on avionics |
On 17 Apr 2008, at 23:29, Mike wrote:
>
> Read the regulation. It says that the 'encoder' must meet the TSO
> standards. It doesn't say that it must be TSO'd. That is a subtle
> legal difference.
>
>
But, if you read the TSO standards you would likely conclude that it
would be a very expensive and difficult job to do the testing to
determine whether the item met those standards. If the item must
meet all the TSO standards, it would almost certainly be more
practical simply to purchase a TSO'd item.
In the specific case of altimeters and altimeter encoders, the regs
provide an alternative - as others have noted you can comply with (b)
OR (c).
--
Kevin Horton
RV-8 (FInal Assembly)
Ottawa, Canada
http://www.kilohotel.com/rv8
________________________________________________________________________________
| Subject: | Re: Questions on avionics |
| From: | "rampil" <ira.rampil(at)gmail.com> |
And of course, I was referring to encoding altimeters when I said there
was no requirement for TSO. Transponders must be TSO
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177582#177582
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
Jeff,
Unless you live on the South Pole in the middle of winter, there is no
way
that normal grommets, as you described them, will just split apart and
fall
off!! The expansion/contraction of the aluminum is so small as to not
be a
factor.
Are you sure someone didn't cut them off, just to play a mind game with
you??
Roger
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]
On Behalf Of
Jeff
Page
Sent: Wednesday, April 16, 2008 10:53 AM
Subject: AeroElectric-List: Grommets
I was surprised to find halves of grommets lying on the floor of
my
hangar the other day. In January, they were installed in the
leading
edge ribs. It has been too cold here in Toronto to do much work
on my
plane since then.
As far as I can tell, the holes in the aluminum ribs shrunk from
the
cold and cut the grommets in half. I am glad I found this out
before
pulling all the wires through !
The holes were drilled a hair smaller than the grommets, which fit
nicely without bunching up. The holes were carefully deburred and
I
can rotate my finger in the holes without feeling a sharp edge.
The grommets I purchased from Spaenaur rather than the local
hardware
store. They are specd as material: SBR, hardness: 60 durometer
+/-5.
Are these grommets the wrong material ?
Should there be slack around the grommet when fitted in the hole ?
Some other problem I haven't thought of ?
Thanks,
Jeff Page
Dream Aircraft Tundra #10
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: pinout for Softcom ATC-P intercom?? |
>
>
>Can anyone point me to an installation manual (or just the pin IDs of the
>dB25) for a Softcom ATC-P intercom?
>
>I thought there was a collection of installation diagrams on the
>Aeroelectric site, but I've been unable to locate it.
The pinout guide for a limited number of products
can be found at:
http://www.aeroelectric.com/Installation_Data/
However, these installation aids are the gleaned
from publications that favored a lot of legacy
products (20+ years old).
I did a websearch for Softcom installation data
and didn't have any luck in the time I had to spend
on it. A phone call to Softcom would probably yield
the knowledge as to whether a website resource would
produce the data you need.
In the mean time, if anyone has the documentation
covering any version of a Softcom product and could
either produce a good scan or loan it to me for scanning,
I'd be happy to add the data to the library.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Questions on avionics |
>
>On 17 Apr 2008, at 23:29, Mike wrote:
>
>>
>>Read the regulation. It says that the 'encoder' must meet the TSO
>>standards. It doesn't say that it must be TSO'd. That is a subtle
>>legal difference.
>>
>
>
>But, if you read the TSO standards you would likely conclude that it
>would be a very expensive and difficult job to do the testing to
>determine whether the item met those standards. If the item must
>meet all the TSO standards, it would almost certainly be more
>practical simply to purchase a TSO'd item.
You got that right. The actual testing is the cheap part.
I used to qualify products intended for use on TC aircraft
based on oversight of a single FAA representative for the
engineering testing in my lab. Nowadays, you first have to
get permission to test, then write up a test plan that speaks
to what color the walls of the lab will be painted, then schedule
a bevy of official dispensers of holy-water and witnesses
for testing (most of whom don't have a clue about how your
product works) and the accomplish this all in a laboratory that
is "certified" down to whether or not the paint cited in
the test plan has lead in it. Finally you have to write a test
report. Documents that support various phases of the test
effort must be submitted to the local ACO who is not just
allowed but EXPECTED to take 91 days to pray over it before
granting a blessing. If they do any red-lining, then they'll
take another 91 days to reconsider the changes. In the
mean time, the project team is still banging the project
work-order.
The value-added activity for proving that a product
meets its cited design goals is dwarfed by the no-value-added
activities foisted upon us those-who-know-more-about-airplanes-
than-we-do. If anyone really believes that last week's
air transportation debacle had anything to do with real
passenger safety is sadly deluded. It has everything to
do with lawmakers and regulators activities that
expand kingdoms over which they reign thereby justifying
their fat retirement packages.
The saddest part is that my contemporaries in the TC
aircraft world are so distracted by requirements to dance
to somebody else's orchestra that they're not building their
ability to be good engineers. That's what I'm getting paid
those big bucks for now . . . but I'm always watching for
some bright young bucks to whom I might pass the torch.
I think I've found a couple of new hires at HB that
show great promise. I've already conspired with their
boss to shield them as much as possible from the forces
that would dilute their curiosity, creative juices and
enthusiasm for their jobs.
In the mean time, you who are members of the 'unwashed'
must suffer the effects of all this pomp-and-circumstance
and be content with the dream that "their hearts are in
the right place . . . they're only concerned about your
safety." But if you had a non-TSO'd encoder that lacked
your confidence as to suitability to task, we could probably
assuage those concerns in one day of playing around in
the lab. To get real TSO blessings on the product would
require a 6-12 month, 400+ man-hour effort.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | "Chubby" wires and fuseblocks |
>Comments/Questions: I dont' undestand how to connect large current loads
>to FASTON fuse blocks.
>
>Max wire into FASTON seems to be #10
>
>Fuses up 30A are sold by B&C
>
>Most #10 wire is not rated for 30A.
I don't know of any #10 wire that is not rated for
30A in airplanes.
>What am I missing?
>
I don't recommend any fuses beyond 14AWG/15A be used
in the fuse blocks. What systems are you wiring
that demand the use of larger wire/fuses?
>That's not the question. I want to understand the "faston technology" Why
>does
>Tyco et. el. make fuses that apparently are larger than the wire they are
>designed to protect?
>
>Thanks
I'm not sure I understand the question. Tyco doesn't make
fuses. Bussmann, Littlefuse, and contemporaries do. Neither
one makes wire. It's the system designer's task to consider
suitability of each component to the task based on manufacturer's
specifications and their own experience bolstered perhaps by
in-house testing.
Selection of components for assembling into a system is
usually accomplished by "erring on the safe side." E.g.,
de-rating the devices such that no combination of environmental
conditions put any component at risk. This is the foundation
for my recommendation that we not use anything larger than 15A
fuses in the fuse blocks contrary to the manufacturer's ratings
of 30A combined with Bussmann's willingness to supply a 30A
fuse that fits the hole in a fuse block they designed.
At the same time, 10AWG wire is generally good for 30A
in all but the warmest environments and cheesiest insulation.
If design goals for a design drive us to push a combination
of components out to the boundaries of their performance limits,
then designers are obligated to do a lot of analysis and
probably testing to confirm that analysis. In most cases,
the qualification effort for an optimized design far exceeds
value received for the finished product.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | Jeff Page <jpx(at)Qenesis.com> |
AeroElectric-List Digest Server wrote:
> *
>
> =================================================
> Online Versions of Today's List Digest Archive
> =================================================
>
> Today's complete AeroElectric-List Digest can also be found in either of the
> two Web Links listed below. The .html file includes the Digest formatted
> in HTML for viewing with a web browser and features Hyperlinked Indexes
> and Message Navigation. The .txt file includes the plain ASCII version
> of the AeroElectric-List Digest and can be viewed with a generic text editor
> such as Notepad or with a web browser.
>
> HTML Version:
>
>
> http://www.matronics.com/digest/digestview.php?Style=82701&View=html&Chapter 08-04-17&Archive=AeroElectric
>
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>
>
> http://www.matronics.com/digest/digestview.php?Style=82701&View=txt&Chapter 08-04-17&Archive=AeroElectric
>
>
> ===============================================
> EMail Version of Today's List Digest Archive
> ===============================================
>
>
> ----------------------------------------------------------
> AeroElectric-List Digest Archive
> ---
> Total Messages Posted Thu 04/17/08: 22
> ----------------------------------------------------------
>
>
> Today's Message Index:
> ----------------------
>
> 1. 04:49 AM - Re: Ground Power - Z31A (Robert L. Nuckolls, III)
> 2. 04:56 AM - Re: Re: Rear Mounted Batteries - more questions
> (Robert L. Nuckolls, III)
> 3. 05:49 AM - "Chubby" wires and fuseblocks (Robert L. Nuckolls, III)
> 4. 06:13 AM - Switch ratings (Robert L. Nuckolls, III)
> 5. 06:17 AM - Re: Grommets (Jeff Page)
> 6. 07:06 AM - Re: Grommets (Bubblehead)
> 7. 07:35 AM - Re: Re: Grommets ()
> 8. 07:56 AM - Re: Re: Grommets (Bob White)
> 9. 07:57 AM - Re: Grommets (RALPH HOOVER)
> 10. 01:39 PM - Re: Re: Grommets (Rob Housman)
> 11. 02:00 PM - Re: Re: Grommets (Bryan)
> 12. 02:14 PM - Thermal expansion (was Grommets) (raymondj)
> 13. 03:12 PM - Re: Rear Mounted Batteries - more questions (n277dl)
> 14. 05:44 PM - A Bit of Help, Please (Speedy11(at)aol.com)
> 15. 06:44 PM - Re: A Bit of Help, Please (Joemotis(at)aol.com)
> 16. 06:55 PM - Questions on avionics ()
> 17. 07:13 PM - pinout for Softcom ATC-P intercom?? (Charlie England)
> 18. 07:22 PM - Re: A Bit of Help, Please (Robert L. Nuckolls, III)
> 19. 07:42 PM - Re: Re: Transponder for sale (mode S) (Charlie England)
> 20. 07:48 PM - Re: Questions on avionics (Ernest Christley)
> 21. 08:28 PM - Re: Questions on avionics (Mike)
> 22. 08:34 PM - Re: Questions on avionics (Mike)
>
>
> ________________________________ Message 1
> _____________________________________
>
>
> From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
> Subject: Re: AeroElectric-List: Ground Power - Z31A
>
>
>
>>
>> Bob
>>
>> Please can you confirm the correct procedure for using the ground power on
>> Z31a architecture.
>>
>> Is it imperative to first switch on the "ground power" switch, before
>> switching on the master switch?
>
> No. The ground power may be turned on at any time in the
> starting sequence without regard to damage to the system.
> The ground power circuits as depicted are reverse polarity
> and ov protected . . .
>
>> Would I just switch ground power off, once the aircraft has started?
>
> Yes.
>
>
>> What would happen if ground power switch was inadvertantly left on for an
>> indefinite period, or turned on whilst the aircraft engine was running?
>
> No big deal. IF the ground power source voltage was set
> higher than your ship's regulator, your alternator
> would not come on line and pick up system loads as long
> as the ground power was connected. If you're getting a
> start from a battery cart - as ship's systems came
> alive, your ship's alternator would begin to charge/
> re-charge ALL batteries in the system . . . including those
> in a still connected ground power cart.
>
> If you're using external power from an engine driven or
> AC mains powered cart, then would would expect the external
> voltage source to be set at "battery charging" voltage
> levels (14.2 or 28.5). In this case, you could turn on
> ground power long before closing the master switch and
> let ground power replenish you ship's battery. After
> 15 minutes or so, your ship's battery may well contain
> sufficient snort to start your engine and ground power
> could be disconnected for the start an subsequent
> pre-flight. If the ground power is a battery cart,
> then no charging of the ship's battery can take place
> and you're obligated to use ground power to get the
> engine started. After starting, you'd want to turn
> ground power off so that ALL of your ship's alternator
> output was being used to replenish stored energy in
> the ship's battery.
>
> In cold weather, you may wish to use ground power
> as a routine assist for getting the engine
> started even if your battery is in good shape.
>
> Aside from the possibility of too much ground power
> voltage and/or reversed polarity, there are no risks to
> your airplane's systems that warrant concern. Making
> ground power managed from the pilot's seat
> puts you in control of this resource for the purpose
> of addressing the task at hand.
>
> It's an energy management problem with solutions
> determined by equipment available, condition of
> your battery and immediate goals. I recall reading
> a story many moons ago where a pilot used his ground
> power jumper cables to get his car started using
> his airplane's battery after returning from a trip
> and finding the car battery was not up to the task.
>
>> Your assistance as always is appreciated.
>
> Pleased to be of service sir!
>
> Bob . . .
>
>
> ________________________________ Message 2
> _____________________________________
>
>
> From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
> Subject: Re: AeroElectric-List: Re: Rear Mounted Batteries - more questions
>
>
>
>>
>> Bob and list,
>> Using the previously attached document as reference...
>>
>> Assumptions... rear mounted batteries. Main Bat Cntctr, Aux Bat cntctr
>> and Xfeed Cntctr all mounted in rear beside the batteries.
>
> Hmmmm . . . normally we'd like to see the cross-feed contactor
> mounted on the firewall. This provides nice fat-wire terminals
> from both batteries to serve as distribution points for the
> two batteries in addressing their respective tasks.
>
>> 2awg ground wire to fwd central gnd bus attached to the engine via stud
>> through firewall. XFEED cnctr closed for starting. 2AWG wire from the
>> same side of XFEED cntctr that the main bat cntctr is connected to
>> starter cntctr.
>
> Okay . . .
>
>> Questions.... Can I then run appropriate sized wire (tbd) from the same
>> side of the starter cntctr as the 2awg wire is attached to the main pwr bus?
>
> Yes. If your cross-feed contactor were up front
> then the battery distribution tie point would be
> on the cross-feed contactor. With the configuration
> you've described, then the starter contactor becomes
> the tie point.
>
>
>> If so, I also assume I would run appropriate sized wire ~8-10 awg (but not
>> the heavy 2awg) from aux bat side of the XFEED to the Aux bus and use same
>> wire to from the aux alt (prob 8 amp b&C alternator).
>
> Oops . . . sounds like you're describing a Z-14
> architecture using an SD-8 on the aux side. Not
> recommended due to aux battery contactor loads being
> such a significant portion of the SD-8's output.
> Suggest a Z-13 architecture is more appropriate to
> maximizing the capabilities of the SD-8.
>
>
>> Hope this makes sense. Really just trying to understand if I can only run
>> two fat wires from the batteries to the firewall if I want to ground at
>> the firewall or need to pull the extra "hot fat wire".
>
> Let's talk about your architecture and choices
> of hardware to fill the various slots. What
> shortcomings do you perceive with a Z-13 architecture
> that drives you toward dual batteries?
>
> Bob . . .
>
>
> ----------------------------------------)
> ( . . . a long habit of not thinking )
> ( a thing wrong, gives it a superficial )
> ( appearance of being right . . . )
> ( )
> ( -Thomas Paine 1776- )
> ----------------------------------------
>
>
> ________________________________ Message 3
> _____________________________________
>
>
> From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
> Subject: AeroElectric-List: "Chubby" wires and fuseblocks
>
>
>> Comments/Questions: I dont' undestand how to connect large current loads
>> to FASTON fuse blocks.
>>
>> Max wire into FASTON seems to be #10
>>
>> Fuses up 30A are sold by B&C
>>
>> Most #10 wire is not rated for 30A.
>
> I don't know of any #10 wire that is not rated for
> 30A in airplanes.
>
>
>> What am I missing?
>>
>
> I don't recommend any fuses beyond 14AWG/15A be used
> in the fuse blocks. What systems are you wiring
> that demand the use of larger wire/fuses?
>
> Bob . . .
>
> ----------------------------------------)
> ( . . . a long habit of not thinking )
> ( a thing wrong, gives it a superficial )
> ( appearance of being right . . . )
> ( )
> ( -Thomas Paine 1776- )
> ----------------------------------------
>
>
> ________________________________ Message 4
> _____________________________________
>
>
> From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
> Subject: AeroElectric-List: Switch ratings
>
>
>> Comments/Questions: Hi Bob,
>>
>> Re: S700-2-10 switch
>>
>> What is the current rating for this switch?
>
> The S700 series switches are Carling G-series devices.
> The data sheet for this line of products may be reviewed
> at:
>
> http://www.aeroelectric.com/Mfgr_Data/Switches/Carling_G-series.pdf
>
> Note that these are rated at up to 20A in 120VAC systems.
> In the article at:
>
> http://aeroelectric.com/articles/Switch_Ratings.pdf
>
> we explore the simple ideas behind current ratings
> and service life of switches as installed in various
> working environments.
>
>> I would like to use this switch to turn on rotating beacons (12 amps) and
>> strobe lights (11 amps) using the circuit in figure 11-18 (page 11-19) in
>> the 11th edition of your book. The B&C catalog lists the rating as '15VAC
>> maximum'. How does this rating apply to a 14 volt system?
>> My application would run 23 amps through the switch. Will the switch
>> handle this load?
>
> Yes, you'll probably get a satisfactory service life
> using the S700-2-10 for this application. But I'm curious
> as to where you got these current values. I'm also curious
> as to why you have a combination of strobes and rotating
> beacons on the same airplane.
>
> Bob . . .
>
> ----------------------------------------)
> ( . . . a long habit of not thinking )
> ( a thing wrong, gives it a superficial )
> ( appearance of being right . . . )
> ( )
> ( -Thomas Paine 1776- )
> ----------------------------------------
>
>
> ________________________________ Message 5
> _____________________________________
>
>
> From: Jeff Page <jpx(at)Qenesis.com>
> Subject: AeroElectric-List: Re: Grommets
>
>
> Mark,
>
> Here is the link to the grommet info:
> http://www.spaenaur.ca/pdf/sectionJ/J69.pdf
> The grommets are not all the same size, but most are 315-263. So the
> groove diameter is 7/16 and I would have drilled 27/64" holes.
> I think the ribs are 6061-T6 32 thou.
> Unfortunately, I have a bad cold, so I won't be able to visit the
> hangar to take photos. If you held a grommet in your fingers and
> sliced it vertically with a dull knife, tearing as well as cutting,
> that's what they look like.
> I pushed the grommets in when it was about freezing temperature, but
> they were still quite pliable. They were not difficult to install
> using just my fingers. It didn't run any wire or conduit in them,
> just left them there. The frame of the wing is rivetted, but the
> skins are not on it yet. It is just sitting on the workbench.
>
> As long as the SBR material is considered aviation quality, I expect I
> just need larger holes.
>
> Jeff
>
>> From: <Flagstone(at)cox.net>
>> Subject: Re: AeroElectric-List: Grommets
>>
>> Your finding has me concerned. Could you provide the following details:
>>
>> 1 Grommet Dimensions or Spaenaur part #:
>> Inside Diameter
>> Groove Diameter
>> Outside Diameter
>> Groove Width
>> Overall Thickness
>>
>> 2 Hole Diameter
>>
>> 3 Rib thickness
>>
>> Were the wires in conduit? If so what was the outside diameter of the
>> conduit.
>>
>> Do you have a pic of the installed grommet and the split grommet you can
>> post?
>
>
> ________________________________ Message 6
> _____________________________________
>
>
> Subject: AeroElectric-List: Re: Grommets
> From: "Bubblehead" <jdalman2000(at)yahoo.com>
>
>
> rob(at)hyperion-ef.com wrote:
>> While not disputing that the grommets failed, I must question your
>> explanation. The coefficient of thermal expansion for aluminum alloy 3003
>> (a common sheet alloy) is 12.9 microinch/inch deg F, so doing the math for a
>> 1 inch diameter hole and a temperature change from a really hot 100 deg F
>> day for installation and a really cold minus 50 deg F day during the winter
>> you get a worst case diameter change of slightly less than .002 inch. A
>> half inch diameter hole would change less than .001 inch for the same
>> temperature change.
>>
>> Installing the grommets into an undersize hole, thus stressing the grommet,
>> is probably the culprit, not contraction alone.
>>
>>
>> Best regards,
>>
>> Rob Housman
>> Irvine, CA
>> Europa XS Tri-Gear
>> A070
>> Airframe complete
>>
>> --
>
>
> Rob - I think you're using the coefficient for the aluminum and then
> computing
> the change based on the size of the hole. The change in hole size is
> because of
> the change in the aluminum size. 1" or 1/2" hole doesn't matter -
> only the amount
> of aluminum around the hole!
>
> Actually, as the aluminum cools wouldn't it contract, making the
> hole bigger? The
> temperature would have to rise so the aluminum expands to make the
> hole smaller.
>
>
> My opinion is the bushings got brittle and maybe had flaws or
> residual stresses
> that made them break. I doubt change in hole diameter had anything to do with
> it.
>
> John
>
> --------
> John Dalman
> Elburn, IL
> RV-8 N247TD
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=177406#177406
>
>
> ________________________________ Message 7
> _____________________________________
>
>
> From: <Flagstone(at)cox.net>
> Subject: Re: AeroElectric-List: Re: Grommets
>
>
> Jeff:
>
> That's all I need to work with. Thanks
>
> Hope you feel better
>
> Mark
> ----- Original Message -----
> From: "Jeff Page" <jpx(at)Qenesis.com>
> Sent: Thursday, April 17, 2008 6:14 AM
> Subject: AeroElectric-List: Re: Grommets
>
>
>>
>> Mark,
>>
>> Here is the link to the grommet info:
>> http://www.spaenaur.ca/pdf/sectionJ/J69.pdf
>> The grommets are not all the same size, but most are 315-263. So the
>> groove diameter is 7/16 and I would have drilled 27/64" holes.
>> I think the ribs are 6061-T6 32 thou.
>> Unfortunately, I have a bad cold, so I won't be able to visit the
>> hangar to take photos. If you held a grommet in your fingers and
>> sliced it vertically with a dull knife, tearing as well as cutting,
>> that's what they look like.
>> I pushed the grommets in when it was about freezing temperature, but
>> they were still quite pliable. They were not difficult to install
>> using just my fingers. It didn't run any wire or conduit in them,
>> just left them there. The frame of the wing is rivetted, but the
>> skins are not on it yet. It is just sitting on the workbench.
>>
>> As long as the SBR material is considered aviation quality, I expect I
>> just need larger holes.
>>
>> Jeff
>>
>>> From: <Flagstone(at)cox.net>
>>> Subject: Re: AeroElectric-List: Grommets
>>>
>>> Your finding has me concerned. Could you provide the following details:
>>>
>>> 1 Grommet Dimensions or Spaenaur part #:
>>> Inside Diameter
>>> Groove Diameter
>>> Outside Diameter
>>> Groove Width
>>> Overall Thickness
>>>
>>> 2 Hole Diameter
>>>
>>> 3 Rib thickness
>>>
>>> Were the wires in conduit? If so what was the outside diameter of the
>>> conduit.
>>>
>>> Do you have a pic of the installed grommet and the split grommet you can
>>> post?
>>
>>
>>
>>
>>
>>
>>
>
>
> ________________________________ Message 8
> _____________________________________
>
>
> From: Bob White <bob@bob-white.com>
> Subject: Re: AeroElectric-List: Re: Grommets
>
>
> "Bubblehead" wrote:
>
>
>>
>>
>> Rob - I think you're using the coefficient for the aluminum and
>> then computing
> the change based on the size of the hole. The change in hole size is because
> of the change in the aluminum size. 1" or 1/2" hole doesn't matter - only the
> amount of aluminum around the hole!
>>
>> Actually, as the aluminum cools wouldn't it contract, making the
>> hole bigger?
> The temperature would have to rise so the aluminum expands to make
> the hole smaller.
>
>>
>> My opinion is the bushings got brittle and maybe had flaws or
>> residual stresses
> that made them break. I doubt change in hole diameter had anything to do with
> it.
>>
>> John
>>
>> --------
>> John Dalman
>> Elburn, IL
>> RV-8 N247TD
>>
>>
> Hi John,
>
> When you're looking at the dimensional change in the material, you have
> to look at the overall dimensions of the item. Say you have a piece of
> aluminum 10 inches X 10 inches with a 1 inch dia hole in the center.
> If a drop in temperature causes the material to shrink 0.001 inch per
> inch (just to pick a number), the new dimensions will be 10 thousandths
> less or 9.99 X 9.99 and the inside hole will be .999 inches in dia.
> The size of the internal hole will be the same as if the material was
> still there.
>
>
> Bob W.
>
>
> --
> N93BD - Rotary Powered BD-4 - http://www.bob-white.com
> 3.8 Hours Total Time and holding
> Cables for your rotary installation - http://roblinstores.com/cables/
>
>
> ________________________________ Message 9
> _____________________________________
>
>
> From: "RALPH HOOVER" <hooverra(at)verizon.net>
> Subject: RE: AeroElectric-List: Grommets
>
>
> Jeff,
> Just a guess but exposure to solvents could breakdown SBR. I cannot
> imagine that hole size alone is the issue.
>
> http://www.alliedrubber.com/Gasket/SBRRubber.cfm.htm
>
> "When exposed to petroleum derivatives, the performance of this rubber is
> inferior to many other synthetics. Red SBR rubber is popular for use as a
> gasket in low pressure applications such as washers and gaskets for the
> heating and plumbing trades. Black SBR is commonly used for abrasion
> conditions such as skirtboard and chute lining."
>
> Ralph & Laura Hoover
> RV7A N527LR
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jeff Page
> Sent: Wednesday, April 16, 2008 10:53 AM
> Subject: AeroElectric-List: Grommets
>
>
> I was surprised to find halves of grommets lying on the floor of my
> hangar the other day. In January, they were installed in the leading
> edge ribs. It has been too cold here in Toronto to do much work on my
> plane since then.
>
> As far as I can tell, the holes in the aluminum ribs shrunk from the
> cold and cut the grommets in half. I am glad I found this out before
> pulling all the wires through !
>
> The holes were drilled a hair smaller than the grommets, which fit
> nicely without bunching up. The holes were carefully deburred and I
> can rotate my finger in the holes without feeling a sharp edge.
>
> The grommets I purchased from Spaenaur rather than the local hardware
> store. They are specd as material: SBR, hardness: 60 durometer +/-5.
>
> Are these grommets the wrong material ?
>
> Should there be slack around the grommet when fitted in the hole ?
>
> Some other problem I haven't thought of ?
>
> Thanks,
>
> Jeff Page
> Dream Aircraft Tundra #10
>
>
> ________________________________ Message 10
> ____________________________________
>
>
> From: "Rob Housman" <rob@hyperion-ef.com>
> Subject: RE: AeroElectric-List: Re: Grommets
>
>
> I'm glad to hear that I wasn't the only student that did not fall asleep in
> freshman physics lecture.
>
>
> Best regards,
>
> Rob Housman
> Irvine, CA
> Europa XS Tri-Gear
> A070
> Airframe complete
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob White
> Sent: Thursday, April 17, 2008 7:51 AM
> Subject: Re: AeroElectric-List: Re: Grommets
>
>
> "Bubblehead" wrote:
>
>
>>
>>
>> Rob - I think you're using the coefficient for the aluminum and then
> computing the change based on the size of the hole. The change in hole size
> is because of the change in the aluminum size. 1" or 1/2" hole doesn't
> matter - only the amount of aluminum around the hole!
>>
>> Actually, as the aluminum cools wouldn't it contract, making the hole
> bigger? The temperature would have to rise so the aluminum expands to make
> the hole smaller.
>>
>> My opinion is the bushings got brittle and maybe had flaws or residual
> stresses that made them break. I doubt change in hole diameter had anything
> to do with it.
>>
>> John
>>
>> --------
>> John Dalman
>> Elburn, IL
>> RV-8 N247TD
>>
>>
> Hi John,
>
> When you're looking at the dimensional change in the material, you have
> to look at the overall dimensions of the item. Say you have a piece of
> aluminum 10 inches X 10 inches with a 1 inch dia hole in the center.
> If a drop in temperature causes the material to shrink 0.001 inch per
> inch (just to pick a number), the new dimensions will be 10 thousandths
> less or 9.99 X 9.99 and the inside hole will be .999 inches in dia.
> The size of the internal hole will be the same as if the material was
> still there.
>
>
> Bob W.
>
>
> --
> N93BD - Rotary Powered BD-4 - http://www.bob-white.com
> 3.8 Hours Total Time and holding
> Cables for your rotary installation - http://roblinstores.com/cables/
>
>
> ________________________________ Message 11
> ____________________________________
>
>
> From: "Bryan" <bhcishere(at)ca.rr.com>
> Subject: Re: AeroElectric-List: Re: Grommets
>
>
> Heat makes the hole bigger. Haven't you ever had to remove a stubborn bolt?
> That is done with a torch to make the hole bigger.
>
> Bryan
>
> ----- Original Message -----
> From: "Rob Housman" <rob@hyperion-ef.com>
> Sent: Thursday, April 17, 2008 1:35 PM
> Subject: RE: AeroElectric-List: Re: Grommets
>
>
>> <rob@hyperion-ef.com>
>>
>> I'm glad to hear that I wasn't the only student that did not fall asleep
>> in
>> freshman physics lecture.
>>
>>
>> Best regards,
>>
>> Rob Housman
>> Irvine, CA
>> Europa XS Tri-Gear
>> A070
>> Airframe complete
>>
>> -----Original Message-----
>> From: owner-aeroelectric-list-server(at)matronics.com
>> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob
>> White
>> Sent: Thursday, April 17, 2008 7:51 AM
>> To: aeroelectric-list(at)matronics.com
>> Subject: Re: AeroElectric-List: Re: Grommets
>>
>>
>> "Bubblehead" wrote:
>>
>>
>>>
>>>
>>> Rob - I think you're using the coefficient for the aluminum and then
>> computing the change based on the size of the hole. The change in hole
>> size
>> is because of the change in the aluminum size. 1" or 1/2" hole doesn't
>> matter - only the amount of aluminum around the hole!
>>>
>>> Actually, as the aluminum cools wouldn't it contract, making the hole
>> bigger? The temperature would have to rise so the aluminum expands to make
>> the hole smaller.
>>>
>>> My opinion is the bushings got brittle and maybe had flaws or residual
>> stresses that made them break. I doubt change in hole diameter had
>> anything
>> to do with it.
>>>
>>> John
>>>
>>> --------
>>> John Dalman
>>> Elburn, IL
>>> RV-8 N247TD
>>>
>>>
>> Hi John,
>>
>> When you're looking at the dimensional change in the material, you have
>> to look at the overall dimensions of the item. Say you have a piece of
>> aluminum 10 inches X 10 inches with a 1 inch dia hole in the center.
>> If a drop in temperature causes the material to shrink 0.001 inch per
>> inch (just to pick a number), the new dimensions will be 10 thousandths
>> less or 9.99 X 9.99 and the inside hole will be .999 inches in dia.
>> The size of the internal hole will be the same as if the material was
>> still there.
>>
>>
>> Bob W.
>>
>>
>> --
>> N93BD - Rotary Powered BD-4 - http://www.bob-white.com
>> 3.8 Hours Total Time and holding
>> Cables for your rotary installation - http://roblinstores.com/cables/
>>
>>
>> --
>> Checked by AVG.
>> 9:00 AM
>>
>>
>
>
> ________________________________ Message 12
> ____________________________________
>
>
> From: "raymondj" <raymondj(at)frontiernet.net>
> Subject: AeroElectric-List: Thermal expansion (was Grommets)
>
>
> Listers,
>
> The link below provides info. applicable to the conversation.
>
> http://hyperphysics.phy-astr.gsu.edu/Hbase/thermo/thexp2.html#c1
>
>
> Raymond Julian
> Kettle River, MN
>
> "Hope for the best,
> but prepare for the worst."
>
>
> ________________________________ Message 13
> ____________________________________
>
>
> Subject: AeroElectric-List: Re: Rear Mounted Batteries - more questions
> From: "n277dl" <dljinia(at)yahoo.com>
>
>
> Bob,
> Thanks for the response and heres some more details....
>
> building a rv10, dual grt hx, 430w, sl30, tt - ap, lycoming io540 -
> one lightspeed
> ignition and one mag. Will have basic airspeed round gauges for backup...
> ie groudspeed, vsi, altimeter and an electric gyro attitude indicator. Have
> similar systems in RV7A except dynon not grt, no sl30 and all both mags.
>
> Why two batteries...primarily rumblings on those with efis to the
> need to have
> the two batteries in starting to keep from resetting the boot-up operation of
> the efis's during engine startup (honestly, unverified by me).
> Adding an extra
> battery is an insignificant expense (relatively speaking). Having
> two batteries
> would make me more comfortable with dual electronic ignition in the future.
> I won't start that way as engine already ordered and configured but it's much
> easier to plumb for future than redo later.
>
>
>>
>> Hmmmm . . . normally we'd like to see the cross-feed contactor
>> mounted on the firewall. This provides nice fat-wire terminals
>> from both batteries to serve as distribution points for the
>> two batteries in addressing their respective tasks.
>>
>
>
> In a previous post on the original thread you stated....
>
>>
>> Quote:
>>
>> The crossfeed contactor, starter contactor and current limiter
>> block can be mounted within inches of each other and "wired" with
>> flat strap like the pictures found in this directory . . .
>>
>> http://www.aeroelectric.com/Pictures/Wiring_Technique/
>>
>> The short straps are much easier to fabricate and install than
>> very short hunks of fat wire with terminals.
>>
>> Bob . . .
>>
>
>
> So I'm a little confused. Maybe I took this one out of context and
> was specifically
> directed at firewall mounted batteries.
>
> I've actually already ran the two 2awg fat wires to the front where
> I could mount
> the xfeed contactor but then found the above post and thought maybe it should
> only be one.
>
> I'm on the road this week but will review the z13 tomorrow night.
> Maybe all I
> need and don't need the extra complexity.
>
> Thanks again,
> Doug
>
> --------
> Doug
> "Fools" are always more creative than process people and
> will always
> find ways to ruin a perfectly good set of processes.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=177495#177495
>
>
> ________________________________ Message 14
> ____________________________________
>
>
> From: Speedy11(at)aol.com
> Subject: AeroElectric-List: A Bit of Help, Please
>
> I am installing Whelen LED taxi/recognition lights.
> Each one draws 0.9 amps.
> I am using an DPDT on-off-on switch to operate them. One position for
> steady on, one for flashing. I want to use only one switch instead of two.
> I'm using Eric Jones' wig wag flasher for the recognition mode.
> For the flash switch selection, I've wired one side with leads from the
> flasher module that activate the flash.
> For the steady on switch selection, I've wired power through the other side
> of the switch.
> When in flash mode, to keep power from going back through the wires and
> causing the lights to stay on constantly, I've added zener diodes.
> The diodes are Radio Shack 12v INT4742A. The package says the
> characteristics are current = 21mA and max power dissipation = 1.0W.
> I've tested the lights with the diodes in the power wires for 45 minutes
> without a problem.
> My question is - Are these diodes sufficient for long term use with lights
> drawing 0.9 Amps?
> Thanks in advance,
> Stan Sutterfield
>
>
> **************Need a new ride? Check out the largest site for U.S. used car
> listings at AOL Autos.
> (http://autos.aol.com/used?NCID=aolcmp00300000002851)
>
> ________________________________ Message 15
> ____________________________________
>
>
> From: Joemotis(at)aol.com
> Subject: Re: AeroElectric-List: A Bit of Help, Please
>
> Buy the right ones rated for your load and sleep at night.
> If you cannot afford it, contact me off list and I will mail you a couple :)
>
> Joe Motis
>
> No archivos amigo
>
>
> **************Need a new ride? Check out the largest site for U.S. used car
> listings at AOL Autos.
> (http://autos.aol.com/used?NCID=aolcmp00300000002851)
>
> ________________________________ Message 16
> ____________________________________
>
>
> From: <bakerocb(at)cox.net>
> Subject: AeroElectric-List: Questions on avionics
>
>
> 4/17/2008
>
> Hello Ira,
>
> 1) You wrote: "There is no requirement for TSO in owner built aircraft."**
>
> 2) FAR SEC 91.217 Says:
>
> "Data correspondence between automatically reported pressure
> altitude data and the pilot's altitude reference.
>
> No person may operate any automatic pressure altitude reporting equipment
> associated with a radar beacon transponder-
>
> (a) When deactivation of that equipment is directed by ATC;
>
> (b) Unless, as installed, that equipment was tested and calibrated to
> transmit altitude data corresponding within 125 feet (on a 95 percent
> probability basis) of the indicated or calibrated datum of the altimeter
> normally used to maintain flight altitude, with that altimeter referenced to
> 29.92 inches of mercury for altitudes from sea level to the maximum
> operating altitude of the aircraft; or
>
> (c) Unless the altimeters and digitizers in that equipment meet the
> standards of TSO-C10b and TSO-C88, respectively."
>
> 3) Please explain, with specific valid reference, why the phrase "No person
> may ..." seen above would not apply to a person flying an amateur built
> experimental aircraft.
>
> 4) You are correct that there are alternatives to using TSO'd equipment,
> when such equipment is specifically required by a regulation, provided that
> you can prove to the FAA's satisfaction that your alternative equipment is
> acceptable to the FAA. Here is how you go about doing that:
>
> FAR Sec. 21.609 "Approval for deviation.
>
> (a) Each manufacturer who requests approval to deviate from any performance
> standard of a TSO shall show that the standards from which a deviation is
> requested are compensated for by factors or design features providing an
> equivalent level of safety.
> (b) The request for approval to deviate, together with all pertinent data,
> must be submitted to the Manager of the Aircraft Certification Office for
> the geographic area in which the manufacturer is located. If the article is
> manufactured in another country, the request for approval to deviate,
> together with all pertinent data, must be submitted through the civil
> aviation authority in that country to the FAA."
>
> Obtaining an approval for deviation is not a trivial task and none of the
> manufacturers of non TSO'd altitude encoders contained in their EFIS units
> have done so to my knowledge.
>
> 'OC' Says: "The best investment we can make is the effort to gather and
> understand knowledge."
>
> **PS: This statement is also not correct when it comes to the ELT installed,
> if one is required by FAR Sec 91.207, in an amateur built experimental
> aircraft.
>
> -----------------------------------------------------------------
>
> Subject: Re: Questions on avionics
> From: "rampil" <ira.rampil(at)gmail.com>
>
>
> Re: TSO and altimetry sources
>
> There is no requirement for TSO in owner built aircraft. As I said
> previously, there is only a performance requirement.
>
> Part 23 is a separate issue.
>
> --------
> Ira N224XS
>
>
> ________________________________ Message 17
> ____________________________________
>
>
> From: Charlie England <ceengland(at)bellsouth.net>
> Subject: AeroElectric-List: pinout for Softcom ATC-P intercom??
>
>
> Can anyone point me to an installation manual (or just the pin IDs of
> the dB25) for a Softcom ATC-P intercom?
>
> I thought there was a collection of installation diagrams on the
> Aeroelectric site, but I've been unable to locate it.
>
> Thanks,
>
> Charlie
>
>
> ________________________________ Message 18
> ____________________________________
>
>
> From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
> Subject: Re: AeroElectric-List: A Bit of Help, Please
>
>
>
>> I am installing Whelen LED taxi/recognition lights.
>> Each one draws 0.9 amps.
>> I am using an DPDT on-off-on switch to operate them. One position for
>> steady on, one for flashing. I want to use only one switch instead of two.
>> I'm using Eric Jones' wig wag flasher for the recognition mode.
>> For the flash switch selection, I've wired one side with leads from the
>> flasher module that activate the flash.
>> For the steady on switch selection, I've wired power through the other
>> side of the switch.
>> When in flash mode, to keep power from going back through the wires and
>> causing the lights to stay on constantly, I've added zener diodes.
>> The diodes are Radio Shack 12v INT4742A. The package says the
>> characteristics are current = 21mA and max power dissipation = 1.0W.
>> I've tested the lights with the diodes in the power wires for 45 minutes
>> without a problem.
>> My question is - Are these diodes sufficient for long term use with lights
>> drawing 0.9 Amps?
>> Thanks in advance,
>> Stan Sutterfield
>
> It's not clear as to why you selected Zener diodes for this
> task. Zeners are for voltage regulation . . . and it seems
> that the task you're describing uses the diodes to prevent
> reverse current flow under some conditions. Now, if you've
> used a 1N4742 zener in the forward biased mode to replace
> a simple rectifier diode, then the current ratings stated
> for zener operation do not apply. A 1N4742 forward biased
> zener is probably good for about an amp . . . but in the
> reverse direction, the condition that you want the current
> to be zero, the 12 zener mode of operation will kick in and
> it will cause the difference between your 14v system and the
> 12v rating of the zener to be impressed across parts of the
> system that you want to be completely 'cold'.
>
> See:
>
> http://www.aeroelectric.com/Pictures/Misc/RS_Diodes.jpg
>
> The smallest diode suited to the task would be the
> 1N4001 offered as RS catalog number 276-1101. However,
> higher voltage ratings don't hurt a thing so any of the
> 1N400-series devices could be used.
>
> My personal preference for mechanical robustness are
> the 1N5400-series, 3 amp devices. Again, having a part
> that is electrically "too big" isn't a factor for your
> application. These diodes are about 3x the size
> and have more robust bodies and leadwires. These are
> the diodes shown in this picture:
>
> http://www.aeroelectric.com/Pictures/Contactors/s701-2.jpg
>
> When we were selling this assembly, the fatter diodes
> were selected for ease of assembly and robustness.
>
> Bob . . .
>
> ----------------------------------------)
> ( . . . a long habit of not thinking )
> ( a thing wrong, gives it a superficial )
> ( appearance of being right . . . )
> ( )
> ( -Thomas Paine 1776- )
> ----------------------------------------
>
>
> ________________________________ Message 19
> ____________________________________
>
>
> From: Charlie England <ceengland(at)bellsouth.net>
> Subject: Re: AeroElectric-List: Re: Transponder for sale (mode S)
>
>
> Ernest Christley wrote:
>>
>>
>> Michael Pereira wrote:
>>>
>>>
>>> I don't really understand this. The cost of avionics is because of the
>>> low volume and the liability costs. Implementing Linux isn't going to
>>> cut the costs more than 20 bucks on a device. This is a huge deduction
>>> for something like a wifi router. It's noise if you're talking about a
>>> device like a garmin 430.
>>>
>>
>> The point wasn't that the OLPC uses Linux. The point was that the
>> technology to implement a self configuring mesh network is both cheap
>> and widespread. The point was that the people in charge think of
>> $3,000 as "low cost", while the same task is being done for <$200.
>>
>> I realize that Garmin has to make a few pennies. I'm also an
>> engineer, and I like to eat, too. But I don't expect the government
>> to legislate that everyone by a Cisco C6500 to use the internet. That
>> sort of equipment is just way overkill for the job. To say that the
>> industry should pursue a technology direction that forces everyone to
>> buy expensive equipment, when the same job can be performed...neigh,
>> is being performed...by much cheaper equipment so that someone can
>> make some money is a broken window argument.
>>
>> Part of the problem is the low volume, as you claim. And so they
>> propose a system that will perpetuate the need to use low volume
>> devices? All that would be required to implement the design goals
>> that I've seen is a white-box GPS, the innards of a PalmVx, and a
>> medium strength transceiver. The software is trivial, considering the
>> number of examples with open source available (ie, the hard part is
>> done already). There's nothing in the mix that would push a
>> marginally successful product into the $3,000 range.
>>
>> I think most people involved with aircraft are jaded to the point they
>> truly believe everything should cost thousands. You have not, because
>> you ask not.
>>
> I'm running a bit behind on emails.
>
> Hi Earnest,
>
> You're right, of course. Anyone notice the activity on the RV list & the
> VAF forum about APRS? Take a look at Sam Buchanan's installation.
> http://home.hiwaay.net/~sbuc/journal/tracker.htm
> The whole setup is only a couple hundred bucks; for a few hundred more,
> you could receive & display the info directly in the cockpit. These
> things do basically everything that ADS-B does, plus a little more. The
> low wattage xmitter (all you need) would fit in the base of a
> streamlined antenna, with just power & serial data lines coming in the
> cockpit. In fact, a dedicated antenna on the top of the plane could
> contain the GPS rcvr & need nothing but power.
>
> Charlie
>
>
> ________________________________ Message 20
> ____________________________________
>
>
> From: Ernest Christley <echristley(at)nc.rr.com>
> Subject: Re: AeroElectric-List: Questions on avionics
>
>
> bakerocb(at)cox.net wrote:
>>
>> 4/17/2008
>>
>> Hello Ira,
>>
>> 1) You wrote: "There is no requirement for TSO in owner built
>> aircraft."**
>>
>> 2) FAR SEC 91.217 Says:
>>
>> "Data correspondence between automatically reported pressure
>> altitude data and the pilot's altitude reference.
>>
>> No person may operate any automatic pressure altitude reporting equipment
>> associated with a radar beacon transponder-
>>
>> (a) When deactivation of that equipment is directed by ATC;
>>
>> (b) Unless, as installed, that equipment was tested and calibrated to
>> transmit altitude data corresponding within 125 feet (on a 95 percent
>> probability basis) of the indicated or calibrated datum of the altimeter
>> normally used to maintain flight altitude, with that altimeter
>> referenced to
>> 29.92 inches of mercury for altitudes from sea level to the maximum
>> operating altitude of the aircraft; or
>>
>> (c) Unless the altimeters and digitizers in that equipment meet the
>> standards of TSO-C10b and TSO-C88, respectively."
>>
>> 3) Please explain, with specific valid reference, why the phrase "No
>> person may ..." seen above would not apply to a person flying an
>> amateur built experimental aircraft.
>
> I don't understand why you think what he said is wrong.
>
> No person may operate any automatic pressure altitude reporting
> equipment ...Unless.... that equipment was tested and calibrated...;
> or...that equipment meet the standards of TSO-C10b and TSO-C88
>
> There's an OR statement there. One, the other, or both can be true, and
> the statement is still true (I'm a Software Engineer by training, so I
> took a special class just for that sort of reasoning 8*)
>
> --
>
> http://www.ronpaultimeline.com
>
>
> ________________________________ Message 21
> ____________________________________
>
>
> From: "Mike" <mlas(at)cox.net>
> Subject: RE: AeroElectric-List: Questions on avionics
>
>
> I would argue that you are not looking for a deviation to the TSO you
> are looking to comply with the standard of the TSO without a formal
> proof.
>
> Mike
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
> bakerocb(at)cox.net
> Sent: Thursday, April 17, 2008 6:51 PM
> ira.rampil(at)gmail.com
> Subject: AeroElectric-List: Questions on avionics
>
>
> 4/17/2008
>
> Hello Ira,
>
> 1) You wrote: "There is no requirement for TSO in owner built
> aircraft."**
>
> 2) FAR SEC 91.217 Says:
>
> "Data correspondence between automatically reported pressure
> altitude data and the pilot's altitude reference.
>
> No person may operate any automatic pressure altitude reporting
> equipment
> associated with a radar beacon transponder-
>
> (a) When deactivation of that equipment is directed by ATC;
>
> (b) Unless, as installed, that equipment was tested and calibrated to
> transmit altitude data corresponding within 125 feet (on a 95 percent
> probability basis) of the indicated or calibrated datum of the altimeter
> normally used to maintain flight altitude, with that altimeter
> referenced to
> 29.92 inches of mercury for altitudes from sea level to the maximum
> operating altitude of the aircraft; or
>
> (c) Unless the altimeters and digitizers in that equipment meet the
> standards of TSO-C10b and TSO-C88, respectively."
>
> 3) Please explain, with specific valid reference, why the phrase "No
> person
> may ..." seen above would not apply to a person flying an amateur built
> experimental aircraft.
>
> 4) You are correct that there are alternatives to using TSO'd equipment,
>
> when such equipment is specifically required by a regulation, provided
> that
> you can prove to the FAA's satisfaction that your alternative equipment
> is
> acceptable to the FAA. Here is how you go about doing that:
>
> FAR Sec. 21.609 "Approval for deviation.
>
> (a) Each manufacturer who requests approval to deviate from any
> performance
> standard of a TSO shall show that the standards from which a deviation
> is
> requested are compensated for by factors or design features providing an
>
> equivalent level of safety.
> (b) The request for approval to deviate, together with all pertinent
> data,
> must be submitted to the Manager of the Aircraft Certification Office
> for
> the geographic area in which the manufacturer is located. If the article
> is
> manufactured in another country, the request for approval to deviate,
> together with all pertinent data, must be submitted through the civil
> aviation authority in that country to the FAA."
>
> Obtaining an approval for deviation is not a trivial task and none of
> the
> manufacturers of non TSO'd altitude encoders contained in their EFIS
> units
> have done so to my knowledge.
>
> 'OC' Says: "The best investment we can make is the effort to gather and
> understand knowledge."
>
> **PS: This statement is also not correct when it comes to the ELT
> installed,
> if one is required by FAR Sec 91.207, in an amateur built experimental
> aircraft.
>
> -----------------------------------------------------------------
>
> Subject: Re: Questions on avionics
> From: "rampil" <ira.rampil(at)gmail.com>
>
>
> Re: TSO and altimetry sources
>
> There is no requirement for TSO in owner built aircraft. As I said
> previously, there is only a performance requirement.
>
> Part 23 is a separate issue.
>
> --------
> Ira N224XS
>
>
> 10/2/2007 11:10 AM
>
>
> 10/2/2007 11:10 AM
>
>
> ________________________________ Message 22
> ____________________________________
>
>
> From: "Mike" <mlas(at)cox.net>
> Subject: RE: AeroElectric-List: Questions on avionics
>
>
> Read the regulation. It says that the 'encoder' must meet the TSO
> standards. It doesn't say that it must be TSO'd. That is a subtle
> legal difference.
>
> Mike
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
> Ernest Christley
> Sent: Thursday, April 17, 2008 7:51 PM
> Subject: Re: AeroElectric-List: Questions on avionics
>
>
>
> bakerocb(at)cox.net wrote:
>>
>> 4/17/2008
>>
>> Hello Ira,
>>
>> 1) You wrote: "There is no requirement for TSO in owner built
>> aircraft."**
>>
>> 2) FAR SEC 91.217 Says:
>>
>> "Data correspondence between automatically reported pressure
>> altitude data and the pilot's altitude reference.
>>
>> No person may operate any automatic pressure altitude reporting
> equipment
>> associated with a radar beacon transponder-
>>
>> (a) When deactivation of that equipment is directed by ATC;
>>
>> (b) Unless, as installed, that equipment was tested and calibrated to
>> transmit altitude data corresponding within 125 feet (on a 95 percent
>> probability basis) of the indicated or calibrated datum of the
> altimeter
>> normally used to maintain flight altitude, with that altimeter
>> referenced to
>> 29.92 inches of mercury for altitudes from sea level to the maximum
>> operating altitude of the aircraft; or
>>
>> (c) Unless the altimeters and digitizers in that equipment meet the
>> standards of TSO-C10b and TSO-C88, respectively."
>>
>> 3) Please explain, with specific valid reference, why the phrase "No
>> person may ..." seen above would not apply to a person flying an
>> amateur built experimental aircraft.
>
> I don't understand why you think what he said is wrong.
>
> No person may operate any automatic pressure altitude reporting
> equipment ...Unless.... that equipment was tested and calibrated...;
> or...that equipment meet the standards of TSO-C10b and TSO-C88
>
> There's an OR statement there. One, the other, or both can be true, and
>
> the statement is still true (I'm a Software Engineer by training, so I
> took a special class just for that sort of reasoning 8*)
>
> --
>
> http://www.ronpaultimeline.com
>
>
> 10/2/2007 11:10 AM
>
>
> 10/2/2007 11:10 AM
>
>
________________________________________________________________________________
| From: | Jeff Page <jpx(at)Qenesis.com> |
In this case, the grommets were not exposed to anything other than
temperature change. I took them out of the box, installed them in the
ribs and let them wait in the cold until things warmed up and I could
continue my work.
The rubber is soft enough that I think the holes would have to become
dramatically smaller to cut the grommets.
Since 15 or 20 of them were halved, I don't think it is just a
defective grommet. I will be inspecting all the rest when I get back
to the hangar.
Assuming I started cuts in the grooves during installation, I still
wouldn't expect to find them in half on the floor :-(
Jeff
> Jeff,
> Just a guess but exposure to solvents could breakdown SBR. I cannot
> imagine that hole size alone is the issue.
>
> http://www.alliedrubber.com/Gasket/SBRRubber.cfm.htm
>
> "When exposed to petroleum derivatives, the performance of this rubber is
> inferior to many other synthetics. Red SBR rubber is popular for use as a
> gasket in low pressure applications such as washers and gaskets for the
> heating and plumbing trades. Black SBR is commonly used for abrasion
> conditions such as skirtboard and chute lining."
>
> Ralph & Laura Hoover
> RV7A N527LR
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Rear Mounted Batteries - more questions |
>
>Bob,
> Thanks for the response and heres some more details....
>
>building a rv10, dual grt hx, 430w, sl30, tt - ap, lycoming io540 - one
>lightspeed ignition and one mag. Will have basic airspeed round
>gauges for backup... ie groudspeed, vsi, altimeter and an electric gyro
>attitude indicator. Have similar systems in RV7A except dynon not grt, no
>sl30 and all both mags.
>
>Why two batteries...primarily rumblings on those with efis to the need to
>have the two batteries in starting to keep from resetting the boot-up
>operation of the efis's during engine startup (honestly, unverified by
>me). Adding an extra battery is an insignificant expense (relatively
>speaking). Having two batteries would make me more comfortable with dual
>electronic ignition in the future. I won't start that way as engine
>already ordered and configured but it's much easier to plumb for future
>than redo later.
>
>
> >
> > Hmmmm . . . normally we'd like to see the cross-feed contactor
> > mounted on the firewall. This provides nice fat-wire terminals
> > from both batteries to serve as distribution points for the
> > two batteries in addressing their respective tasks.
> >
>
>
>In a previous post on the original thread you stated....
>
> >
> > Quote:
> >
> > The crossfeed contactor, starter contactor and current limiter
> > block can be mounted within inches of each other and "wired" with
> > flat strap like the pictures found in this directory . . .
> >
> > http://www.aeroelectric.com/Pictures/Wiring_Technique/
> >
> > The short straps are much easier to fabricate and install than
> > very short hunks of fat wire with terminals.
> >
> > Bob . . .
> >
>
>
>So I'm a little confused. Maybe I took this one out of context and was
>specifically directed at firewall mounted batteries.
>
>I've actually already ran the two 2awg fat wires to the front where I
>could mount the xfeed contactor but then found the above post and thought
>maybe it should only be one.
>
>I'm on the road this week but will review the z13 tomorrow night. Maybe
>all I need and don't need the extra complexity.
>
>Thanks again,
>Doug
My apologies, I may have stuck my foot in it . . . my reason
is too many balls in the air at once . . . but no excuses.
Have I seen a power distribution diagram on your project? My
mental images of our discussion may well be tainted with
artifacts from discussions on other projects. My comment about
x-feed contactor on the firewall was based on some discussions
about rear mounted batteries when I produced a sketch that
looked like this:
http://www.aeroelectric.com/Pictures/Schematics/Z-14_w_Rear_Batteries_Metal_Aircraft.pdf
The thrust of this reasoning addressed the need to
have a convenient, robust place to tie off fatwires that
come forward from rear mounted batteries in a Z14-like
architecture. The most obvious solution was to place
the cross-feed contactor on the firewall irrespective
of where the batteries were located.
This provides the sought-after tie point for tying
the battery fat-wires into the rest of the system.
Let's back-track as needed to make sure my words are
supportive of your design goals. Do you have a z-figure
like drawing to share?
Bob . . .
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: ELT Antenna for Fiberglass aircraft |
Bruce Gray wrote:
>
> I could be wrong but I don't think that dipole antennas are around for 406
> MHTZ ELT's yet. They exist for 121.5 ELT's but they will be obsolete next
> year.
>
You're wrong. Jim Weir's antennae book shows you how to build one that
will handle both frequencies.
http://ernest.isa-geek.org/Delta/Pictures/ELTantennae.jpg
________________________________________________________________________________
| From: | "n801bh(at)netzero.com" <n801bh(at)NetZero.com> |
I will chime in and comment.... This is really hard to believe they spli
t all by themselves. Are you sure someone didn't remove them and split t
hem with a razor and them drop them on the floor as a joke/ prank etc...
Ben Haas
N801BH
www.haaspowerair.com
-- Jeff Page wrote:
In this case, the grommets were not exposed to anything other than
temperature change. I took them out of the box, installed them in the
ribs and let them wait in the cold until things warmed up and I could
continue my work.
The rubber is soft enough that I think the holes would have to become
dramatically smaller to cut the grommets.
Since 15 or 20 of them were halved, I don't think it is just a
defective grommet. I will be inspecting all the rest when I get back
to the hangar.
Assuming I started cuts in the grooves during installation, I still
wouldn't expect to find them in half on the floor :-(
Jeff
> Jeff,
> Just a guess but exposure to solvents could breakdown SBR. I cannot
> imagine that hole size alone is the issue.
>
> http://www.alliedrubber.com/Gasket/SBRRubber.cfm.htm
>
> "When exposed to petroleum derivatives, the performance of this rubber
is
> inferior to many other synthetics. Red SBR rubber is popular for use a
s a
> gasket in low pressure applications such as washers and gaskets for th
e
> heating and plumbing trades. Black SBR is commonly used for abrasion
> conditions such as skirtboard and chute lining."
>
> Ralph & Laura Hoover
> RV7A N527LR
========================
===========
========================
===========
========================
===========
========================
===========
_____________________________________________________________
Save for the future with great IRA Funds. Click now!
http://thirdpartyoffers.netzero.net/TGL2221/fc/Ioyw6i4uDyVs1KdlnZ9jV4Vqr
XwOuYnqBV6CKhvaELy4FmaUxjeMCt/
________________________________________________________________________________
| Subject: | Re: Rear Mounted Batteries - more questions |
| From: | "n277dl" <dljinia(at)yahoo.com> |
Bob.
Started out with your published z14 drawing and began to understand the flow with
them
Then found the string referencing the z14_rough that uses non-local ground. Reviewed
options and decided I wanted to use a central primary ground on the firewall
/ engine block.
That particular string also is where the discussion of keeping the XFEED CNTCTR
and the Battery Cntctrs located close and connected using copper/brass strapping
which drove me to drawing up the very rough sketch with only one + fat wire
running from the back to the front.
I think the biggest weakness of the one wire concept is that I would loose some
of the benefit of the aux alternator as it would have to keep the aux battery
cntctr closed. Think I read in either the connection or the list that it takes
about 1amp to keep the contactor closed. Obviously, Id lose 1/8th of the output
of the SD8 in that scenario. Assuming that its okay to physically mount
the xfeed contactor at the front instead of with the battery contactors, the
only real advantage is one less + fat wire. Would still have to run something
from the Aux alt and aux bus to the rear but it could be a smaller wire.
So all that said, maybe the simplest most efficient design would be moving the
xfeed contactor to the front.
Also pondering the physical location of the battery bus (ie, the always hot bus).
From what I can read it appears the recommendation is always having this bus
physically located within 6-8 inches of the battery. Obviously this requires
running wiring from the front to the back for all devices that you want powered
via the battery bus. An option that I never see mentioned and therefore
assume is a bad idea is to run one heavier wire from the rear mounted battery
and physically locate the battery bus in the front. Again, I assume this is a
bad idea but would you comment on why Im assuming that you wouldnt want a non-fused
wire ran that distance but thought Id ask anyway.
These rear-mounted batteries are requiring some noodling as to where to physically
mount things. Guess that's why they call it experimental :)
Thanks again for all your input. It sure helps to bounce things off someone that
has done this more than once before.
Doug
--------
Doug
"Fools" are always more creative than process people and will always
find ways to ruin a perfectly good set of processes.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177757#177757
Attachments:
http://forums.matronics.com//files/rear_bat_one_fat_wire_fwd_204.pdf
http://forums.matronics.com//files/z_14rough1_204.pdf
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: ELT Antenna for Fiberglass aircraft |
Ernest Christley wrote:
>
>
> Bruce Gray wrote:
>>
>>
>> I could be wrong but I don't think that dipole antennas are around
>> for 406
>> MHTZ ELT's yet. They exist for 121.5 ELT's but they will be obsolete
>> next
>> year.
>>
>
> You're wrong. Jim Weir's antennae book shows you how to build one
> that will handle both frequencies.
>
> http://ernest.isa-geek.org/Delta/Pictures/ELTantennae.jpg
And the 121.5's aren't going to be obsolete next year, at least in the
USA. All that's happening is that the satellites will no longer monitor
that frequency. Not to stir up too much of a firestorm, but loss of
satellite monitoring for 121.5 will make an almost unmeasurable
difference in their lifesaving ability.
Unless the price of certified 406's come down a lot, I'll install a
121.5 & consider buying a 406 PLB. The 121.5 will keep me legal & it
wouldn't be that hard to rig a G-switch on the PLB.
Of course, the APRS stuff is even better if you don't mind being tracked
on a cross country.
Charlie
________________________________________________________________________________
| From: | "Bill and Marsha" <docyukon(at)ptcnet.net> |
A question for Eric Jones Could a Navaids ap1 head drive a mac servo
useing a PD TSCMR And what would be involved? Just an idea!!!!
Bill S.
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Questions on avionics |
4/19/2008
Hello Ira, You wrote: "........I was referring to encoding altimeters when I
said there
was no requirement for TSO."
If that encoding altimeter is the altitude encoder that is feeding the
transponder required by FAR Sec 91.215 then it must comply with either
91.217 (b) or (c). That is what this thread has been about.
See my response to Mike, copied below, for more information.
'OC'
-------------------------------------------------------------
4/18/2008
Hello Mike, Thanks for your three emails. You wrote:
1) "....you are looking to comply with the standard of the TSO without a
formal
proof."
A) I invite you to look at "Subpart O -- TSO Authorizations" of FAR Part 21.
You can access it here:
http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=9dad7a792e03c09e14fc110ded0921cb&rgn=div6&view=text&node=14:1.0.1.3.9.15&idno=14
B) Then I invite you to look at TSO-C10b. You can access it here:
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgTSO.nsf/0/072c91c58fdc6ce686256da4005f4d1b/$FILE/C10b.pdf
C) Then I invite you to look at TSO-C88b. You can access it here:
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgTSO.nsf/0/625ebf9767dac15e8625727c006e10df/$FILE/TSO-C88b.pdf
D) Now I invite you (and here is the gotcha) to procure and look at all the
technical references contained in those TSO's. The TSO's themselves are just
sort of shell documents, pointers if you will. All the real technical guts
and standards that must be complied with are found in the references.
E) Now I ask you to picture the average homebuilder satisfying someone that
he is complying with the standards of the relevant TSO's without formal
proof.
2) "It says that the 'encoder' must meet the TSO standards. It doesn't say
that it must be TSO'd. That is a subtle legal difference."
I accept your "subtle legal difference". After you have gone through steps A
through D above I ask you to picture the average homebuilder satisfying
someone that his non TSO'd altitude encoder is meeting the standards of the
relevant TSO's .
3) "So answer me this: If you the builder /manufacturer determines that
your testing puts the encoder in compliances with the TSO standards......."
Again I ask you to picture the average amateur builder determining that his
testing puts the encoder in compliance with the TSO standards -- not some of
the standards, not just the performance standards, but the all of the TSO
standards. The reason that the EFIS manufacturers have not done this very
thing is because of the significant cost and bureacratic burden involved.
4) "...and you test the unit IAW 43.13 and it passes ......"
A) (I am not sure why you referenced 43.13. It does not appear to be
relevant here. Perhaps you meant FAR Sec 91.413. I will assume so.)
First off I, the amateur builder, am not permitted to perform the tests
required by 91.413 -- see sub paragraph (c) of 91.413.
B) "......what would be the ramifications?"
Second, assuming the tests required by 91.413 were properly performed by a
willing qualified person / entity, the automatic pressure altitude reporting
equipment containing the non TSO'd altitude encoder passed the tests, and
the test results were properly documented there probably would be no adverse
ramifications. But consider this:
B-1) Suppose a willing qualified person / entity is not readily available to
perform the 91.413 required tests because the non TSO'd altitude encoder is
not in compliance with 91.217? What are the ramifications then? Probably no
big deal, go find someone or some place that will perform the tests.
B-2) Suppose that there is a mid air collision between an amateur built
experimental aircraft and an airline aircraft with major loss of life. And
further suppose that the equipment in the amateur built experimental
aircraft had absolutely nothing to do with causing the accident, but the
media learns that the amateur built experimenal aircraft was not in
compliance with some Federal Aviation Regulation (91.217) . What are the
ramifications then?
5) "I don't see a violation of the rule as written."
I am not sure which rule you are referring to. If you are referring to
91.217 there are two choices:
A) Comply with subparagraph (c); ie have equipment that is TSO'd, or
B) Comply with the tests described in subparagraph (b). I think that the
tests required by 91.411 and 91.413 should be considered to meet the
requirements of 91.217 (b). Unfortunately, to date the FAA HQ does not agree
with me and they seem to have a little more authority than I do.
6) "Also their is no enforcement mechanism in place to even determine
whether your in compliance or not."
True enough. I think the FAA is too busy measuring the spacing between
lacings on wire bundles in the wheel wells of airliners to make very many
ramp checks on the avionics installed in amateur built experimental
aircraft, but see the ramifications comments above and make an informed
decision.
7) "You as the aircraft certifying authority as the builder......"
The Special Airworthiness Certificate in the Experimental Category for the
purpose of Operating Amateur Built Aircraft is signed and issued by an FAA
Representative who has been delegated that authority by the FAA
Administrator. The FAA Administrator is the certifying authority, not the
amateur builder.
8) "You ........ as the builder determine suitability as it pertains to the
regulations and no one else"
Try telling that to the FAA employee or DAR who comes to inspect your
amateur built experimental aircraft for its initial airworthiness
inspection. He will set you straight very quickly on who will make the
decisions regarding the suitability of your aircraft as it pertains to
regulations.
9) "Short of them scouring the wreckage for TSO tags they would have to make
an assumption."
I hope that it would never come to that, but the tenacity, search for
details, and the ill will of lawyers and journalists when they smell blood
and money should not be ignored. All I am seeking to do is to have people
make informed decisions -- I provide the information, they make the
decisions.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
-------------------------------------
From: "Mike" <mlas(at)cox.net>
Subject: RE: AeroElectric-List: Questions on avionics
I would argue that you are not looking for a deviation to the TSO you
are looking to comply with the standard of the TSO without a formal
proof.
Mike
-----------------------------------------------------
From: "Mike" <mlas(at)cox.net>
Subject: RE: AeroElectric-List: Questions on avionics
Read the regulation. It says that the 'encoder' must meet the TSO
standards. It doesn't say that it must be TSO'd. That is a subtle
legal difference.
Mike
-----------------------------------------------------
----- Original Message -----
From: "MLAS" <MLAS(at)COX.NET>
Sent: Friday, April 18, 2008 9:37 AM
Subject: Re: Questions on avionics
> So answer me this: If you the builder /manufacturer determines that your
> testing puts the encoder in compliances with the TSO standards and you
> test the unit IAW 43.13 and it passes what would be the ramifications. We
> do live in a country made up by "Common Law" (short def: If it isn't
> prohibited then it's legal). I don't see a violation of the rule as
> written. Also their is no enforcement mechanism in place to even
> determine whether your in compliance or not. You as the aircraft
> certifying authority as the builder determine suitability as it pertains
> to the regulations and no one else. Short of them scouring the wreckage
> for TSO tags they would have to make an assumption.
>
> Mike
--------------------------------------------------------
Subject: AeroElectric-List: Re: Questions on avionics
From: "rampil" <ira.rampil(at)gmail.com>
And of course, I was referring to encoding altimeters when I said there
was no requirement for TSO. Transponders must be TSO
--------
Ira N224XS
________________________________________________________________________________
| Subject: | Re: Questions on avionics |
| From: | "rampil" <ira.rampil(at)gmail.com> |
Again, back to 91.217 (b):
(b) Unless, as installed, that equipment was tested and calibrated to
transmit altitude data corresponding within 125 feet (on a 95 percent
probability basis) of the indicated or calibrated datum of the altimeter
normally used to maintain flight altitude, with that altimeter referenced to
29.92 inches of mercury for altitudes from sea level to the maximum
operating altitude of the aircraft; or
This is just the performance test. It says nothing about TSO.
Part 21 and 23 do not apply to owner built aircraft with special
airworthiness certificates
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177838#177838
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Questions on avionics |
This is not totally theoretical. I am aware of a recent airliner that
took (mandatory) evasive action (and altitude bust) based on erroneous
transponder reporting from a unreported low altitude VFR airplane with
an unknown N number. Such TCAS inspired altitude busts are rare (but not
rare enough) and are usually chalked up to temporary glitches, but you
can see the risk involved. A TCAS RA warning takes precedence over ATC
assigned altitude. It is rare to positively identify the exact cause of
these events but apparently some transponders operate for awhile with
issues before they are discovered. I'd prefer an uncertified encoding
altimeter to a Tso'd blind encoder UNLESS there is any kind of legal
challenge. For the time being I use a Tso'd blind encoder but since I do
not often fly in controlled airspace with ATC altitude feedback, I
occasionally check my transmitted altitude with a PCAS MRX traffic
warning device. I suspect that such issues are one small part of the
drive towards encoding permanent aircraft idents into the newer
transponders.
Ken
> B-2) Suppose that there is a mid air collision between an amateur built
> experimental aircraft and an airline aircraft with major loss of life. And
> further suppose that the equipment in the amateur built experimental
> aircraft had absolutely nothing to do with causing the accident, but the
> media learns that the amateur built experimenal aircraft was not in
> compliance with some Federal Aviation Regulation (91.217) . What are the
> ramifications then?
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: ELT Antenna for Fiberglass aircraft |
>>
>> Bruce Gray wrote:
>>>
>>>
>>> I could be wrong but I don't think that dipole antennas are around
>>> for 406
>>> MHTZ ELT's yet. They exist for 121.5 ELT's but they will be obsolete
>>> next
>>> year.
>>>
>>
>> You're wrong. Jim Weir's antennae book shows you how to build one
>> that will handle both frequencies.
>>
>> http://ernest.isa-geek.org/Delta/Pictures/ELTantennae.jpg
I owe Bruce and apology. It's not until I read a later response that
*406 MHz* sunk into my thick skull.
ELT's use two frequencies; neither of which is 406MHz. You have to
build the dipole antennae to handle both of the frequencies, and that is
what I got caught up on. Not that it would be difficult to build a
406MHz dipole, it would just be shorter, but there is very likely little
to no marketed products at the moment.
My sincerest apologies, Bruce.
--
http://www.ronpaultimeline.com
________________________________________________________________________________
| From: | "Bill and Marsha" <docyukon(at)ptcnet.net> |
Am looking for a site to download Pinout and wiring diagrams for
Navaids AP 1 Autopilot. An install manual would also be nice.
Bill S.
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
| Subject: | Re: A Bit of Help, Please |
Bob,
Thanks for your robust reply. Very helpful.
My intention is to prevent reverse current flow in certain conditions.
I connected the zener diodes in line where needed and did a test of the
system and the diodes did stop the reverse flow of current - as desired. My
concern was that the selected diodes (RS INT4742A - RS part number 276-563) may
not be robust enough to stop the 0.9 Amp current over the long term.
I may as well insert the correct diodes now rather than redo the work at a
later time. So, it sounds like I should change the diodes to another type or
another rating. Correct? Perhaps the 1N5400 series would be best.
Stan Sutterfield
>I am installing Whelen LED taxi/recognition lights.
>Each one draws 0.9 amps.
>I am using an DPDT on-off-on switch to operate them. One position for
>steady on, one for flashing. I want to use only one switch instead of two.
>I'm using Eric Jones' wig wag flasher for the recognition mode.
>For the flash switch selection, I've wired one side with leads from the
>flasher module that activate the flash.
>For the steady on switch selection, I've wired power through the other
>side of the switch.
>When in flash mode, to keep power from going back through the wires and
>causing the lights to stay on constantly, I've added zener diodes.
>The diodes are Radio Shack 12v INT4742A. The package says the
>characteristics are current = 21mA and max power dissipation = 1.0W.
>I've tested the lights with the diodes in the power wires for 45 minutes
>without a problem.
>My question is - Are these diodes sufficient for long term use with lights
>drawing 0.9 Amps?
>Thanks in advance,
>Stan Sutterfield
It's not clear as to why you selected Zener diodes for this
task. Zeners are for voltage regulation . . . and it seems
that the task you're describing uses the diodes to prevent
reverse current flow under some conditions. Now, if you've
used a 1N4742 zener in the forward biased mode to replace
a simple rectifier diode, then the current ratings stated
for zener operation do not apply. A 1N4742 forward biased
zener is probably good for about an amp . . . but in the
reverse direction, the condition that you want the current
to be zero, the 12 zener mode of operation will kick in and
it will cause the difference between your 14v system and the
12v rating of the zener to be impressed across parts of the
system that you want to be completely 'cold'.
See:
http://www.aeroelectric.com/Pictures/Misc/RS_Diodes.jpg
The smallest diode suited to the task would be the
1N4001 offered as RS catalog number 276-1101. However,
higher voltage ratings don't hurt a thing so any of the
1N400-series devices could be used.
My personal preference for mechanical robustness are
the 1N5400-series, 3 amp devices. Again, having a part
that is electrically "too big" isn't a factor for your
application. These diodes are about 3x the size
and have more robust bodies and leadwires. These are
the diodes shown in this picture:
http://www.aeroelectric.com/Pictures/Contactors/s701-2.jpg
When we were selling this assembly, the fatter diodes
were selected for ease of assembly and robustness.
Bob . . .
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Dale Ensing" <densing(at)carolina.rr.com> |
| Subject: | Re: Navaids ap 1 |
Can fax wiring diagram etc. to you if you do not find on a web site.
Dale Ensing
do not archieve
----- Original Message -----
From: Bill and Marsha
To: aeroelectric-list(at)matronics.com
Sent: Saturday, April 19, 2008 2:54 PM
Subject: AeroElectric-List: Navaids ap 1
Am looking for a site to download Pinout and wiring diagrams for
Navaids AP 1 Autopilot. An install manual would also be nice.
Bill S.
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Navaids ap 1 |
Bill and Marsha wrote:
> Am looking for a site to download Pinout and wiring diagrams for
> Navaids AP 1 Autopilot. An install manual would also be nice.
> Bill S.
If you don't find what you need by Monday or Tuesday, email me off-list
& I'll scan it at work (where there's a sheet-feed scanner).
Charlie
________________________________________________________________________________
| From: | Jeff Page <jpx(at)Qenesis.com> |
Two of you both thought my grommet problem so absurd that it must be a prank.
I wish that were true, but my T hangar is locked.
They were exposed only to cold air, darkness, time and my installation.
When I get to the hangar next, i will be taking a close look at all of
them, to see if the ones remaining are partly torn, or if some of them
are perfectly intact.
I will also try to do some tests with some still in the box to see if
I can tear them like that.
Sure is weird though. We install grommets to protect the wires, so
they should be tougher than the insulation.
Jeff
> Are you sure someone didn't cut them off, just to play a mind game with
> you??
>
> Roger
>> Just a guess but exposure to solvents could breakdown SBR. I cannot
>> imagine that hole size alone is the issue.
> I will chime in and comment.... This is really hard to believe they spli
> t all by themselves. Are you sure someone didn't remove them and split t
> hem with a razor and them drop them on the floor as a joke/ prank etc...
>
> Ben Haas
________________________________________________________________________________
| Subject: | Backup Batteries |
| From: | "Chuck Jensen" <cjensen(at)dts9000.com> |
Curious question about the backup battery for a Mid-Continental LifeSaver attitude
indicator with back up battery. While the back up battery is rated for one
hour, actual flight testing, when the battery is new, showed that a duration
of nearly two hours were available, though the battery seems to die after about
three years---disappointing for a +$100 battery.
By way of configuration, the backup battery is fed by plane power to keep charged.
If the plane electrical power is lost, the AI reverts to the battery to keep
its gyro spinning--all very conventional. The question is "is there a credible
scenario whereby the electrical power in the plane is not only lost, but
actually becomes an "electron sink" and pulls those lifesaving electrons out
of the backup battery for the AI, shortening its useful duration? Is this incredible?
Is diode isolation needed on the electrical lines to the backup battery?
Chuck
Velo XLRG
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: A Bit of Help, Please |
>Subject: AeroElectric-List: Re: A Bit of Help, Please
>To: aeroelectric-list(at)matronics.com
>
>
>Bob,
>Thanks for your robust reply. Very helpful.
>My intention is to prevent reverse current flow in certain conditions.
>I connected the zener diodes in line where needed and did a test of the
>system and the diodes did stop the reverse flow of current - as
>desired. My concern was that the selected diodes (RS INT4742A - RS part
>number 276-563) may not be robust enough to stop the 0.9 Amp current over
>the long term.
That's what I understood. I was mystified by the
use of a zener diode. These will "stop reverse flow"
only if the voltage remains below the rating
at which reverse flow is desired and expected . . .
in the case of the 1N4742, 12 volts.
The "ratings" numbers for these devices are
given in there reverse current flow mode of
operation where they dissipate higher power
for the same current flow. Since this package
is generally good for about 1W of dissipation,
their max reverse current should be limited to
about 1w/12v = 0.08 amps. The 0.02 amps you cited
was the "test current" at which the 12v regulation
accuracy was given . . . not the operating
current where the current is dissipation limited.
You're using these devices in their forward
conduction mode where voltage drop is not related
to the zener voltage rating of the device, i.e.
12v but the forward conduction rating which is on
the same order as the ordinary silicon diode
rectifier of about 0.8 volts. Here the same
dissipation limits apply . . . but to get 1w
of heat out of it in the forward mode, you can
now force 1.2a through the device. MUCH larger
than any of the reverse current ratings given
in the 1N4742 data sheet . . . because folks
are generally expect to use theses as reverse
current regulators, not forward current
power steering devices.
http://en.wikipedia.org/wiki/Zener_diode
This is why the 1N4742 didn't smoke during your
extended bench test . . . you were not using it
in the manner described in the data sheets hence
non-hazardous dissipated power at higher than "rated"
currents.
>I may as well insert the correct diodes now rather than redo the work at a
>later time. So, it sounds like I should change the diodes to another type
>or another rating. Correct? Perhaps the 1N5400 series would be best.
The significance of my earlier posting was that
mis-application of the zener as a power steering
device was marginally satisfactory given that
voltages in your system are expected to exceed
the 12v rating of the device whereupon some amount
of reverse current may flow under conditions where
you don't want it to happen. If you picked a zener
that was larger, say 16v or even higher, then
it could be expected to function as you intended
even if it wasn't exactly the right part for the
job.
The silicon rectifier also has a voltage rating
stated as a limit. See:
http://www.diodes.com/datasheets/ds28002.pdf
Note that these little critters are the same
physical size as the 1N4742 but have voltage
limits ranging from 50 to 1000v. Any of these
devices could be used in your application. I
suggested the 5400 series devices be considered
also:
http://www.diodes.com/datasheets/ds28007.pdf
These to are offered in the same ranges of
voltage limits as the 4000 series devices and
while electrically much larger than you need in
this particular case, there's no great transgression
in using such devices at much lower levels
than their rated limits.
In this case, I favor the 5400 series devices
for their mechanical robustness. Larger package,
larger leadwires, much easier to work with in
these situations and less likely to be damaged in
service due to handling.
I think you got sucked into the 12v zener
selection due to a mis-understanding of its
rating as being "appropriate" to your 14v
airplane. The problem was that zeners are
not intended for or generally used as reverse
power blocking devices. The silicon rectifiers
come with lots larger voltage LIMIT ratings
so while much larger than the system voltage
of your aircraft, they are not being mis-applied
by using say a 600v device in your 14v
airplane.
So yes, my recommendation is that you avail yourself
of Radio Shack's standard inventory and substitute
any one of the 5400 series devices for the 1N4742
in the application you've described.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Backup Batteries |
>
>Curious question about the backup battery for a Mid-Continental LifeSaver
>attitude indicator with back up battery. While the back up battery is
>rated for one hour, actual flight testing, when the battery is new, showed
>that a duration of nearly two hours were available, though the battery
>seems to die after about three years---disappointing for a +$100 battery.
They're doing the same thing you would be expected to
to when sizing your e-bus loads in relation to the
size and condition of you ship's battery. The 1 hour
endurance rating should be up to and including the
service life limit of the battery . . . which in this
case is the 3 years that you've cited.
New out of the box, would would expect the battery's
capacity to be higher than at end of life.
>By way of configuration, the backup battery is fed by plane power to keep
>charged. If the plane electrical power is lost, the AI reverts to the
>battery to keep its gyro spinning--all very conventional. The question is
>"is there a credible scenario whereby the electrical power in the plane is
>not only lost, but actually becomes an "electron sink" and pulls those
>lifesaving electrons out of the backup battery for the AI, shortening its
>useful duration? Is this incredible? Is diode isolation needed on the
>electrical lines to the backup battery?
Any designer worth his/her salary would have included
reverse power isolation as part of the product. I.e,
all system failure modes should have been addressed
in the design such that if you install per the
manufacturer's instructions, it will perform as
advertised.
So yes, your question is certainly valid . . . for
which the manufacturer of the product should answer,
"no sweat . . . that's built in."
It's unfortunate that internal backup batteries tend
to be pricey. The attention paid to selection, installation
and maintenance of a backup battery is more rigorous
than for the ship's battery that at least gets "tested"
for internal resistance every flight cycle when you crank
the engine.
But if your project has an e-bus, then you've done
the planning and provided for an un-interruptible
power source. Stacking another $100 battery on top
of this may not offer a good return on investment.
Bob . . .
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Questions on avionics |
4/20/2008
Hello Ira, You wrote:
1) "This is just the performance test."
I assume that you mean the testing required every two years by FAR Sec's
91.411 and 91.413 as appropriate.
I apologize for not having made the situation clearer to you. I also wanted
the testing required by 91.411 / 91.413 to sufficiently meet the
requirements of 91.217 (b) so that one could operate with an EFIS that
contained the only atitude encoder in the airplane and that altitude encoder
would be non TSO'd. So I wrote to FAA HQ asking that question. Here is an
exact quote of their response:
"Your letter posed the following questions:
1. If an amateur built experimental aircraft has an installed TSO'd ATC
transponder as required by Title 14 Code of Federal Regulations (14 CFR)
section 91.215, but a non-TSO'd altitude encoder and the installation has
passed the test and inspection requirements of 14 CFR sections 91.411 and
91.413 within the preceding 24 calendar months, does the installation meet
the requirements of 14 CFR section 91.217(b), and therefore make that
installation acceptable for IFR operations?
2. If the answer to question one is No, can you please tell me
why?
The answer to question one is "No." The testing required to show the
transmitted altitude data corresponds within 125 feet (on a 95 percent
probability basis) is more rigorous than the requirements referenced in 14
CFR sections 91.411, 91.413, and 14 CFR, part 43 appendices E and F. The
tests required by 14 CFR part 43 appendix E(c) measure the automatic
pressure altitude at a sufficient number of test points to ensure the
altitude reporting equipment performs its intended function.
Title 14 CFR section 91.217 paragraphs (b) and (c), state that pressure
altitude reporting equipment must be tested and calibrated to transmit
altitude data correspondence within stated specifications; or, the
altimeters and digitizers must meet the standards in TSO-C10B and TSO-C88,
respectively.
Should the owner/operator elect to exhibit compliance with tests and
calibration provided in 14 CFR section 91.217(b), a test method would need
to be developed that ensures the transmitted data corresponds within 125
feet of the indicated altitudes from sea level to the maximum operating
altitude of the aircraft
on a 95 percent probability basis. This testing also needs to ensure the
performance characteristics of the equipment are not impacted when
subjected to environmental conditions (voltage fluctuations temperature,
vibration, etc.) which may be encountered in airborne operations.
Completed tests and calibration results should be maintained in the
aircraft records.
Thank you for your interest in aviation safety."
So you can see that FAA HQ does not agree with our wishes. Further you can
see that an amateur builder attempting to comply with the FAA HQ version of
the testing requirements of 91.217 (b) in order to avoid having a TSO'd
altitude encoder installed in his airplane would have a very difficult /
impossible time doing so.
2) "It says nothing about TSO."
That is correct. The TSO part is found in 91.217 (c). So the person
mentioned in the beginning of 91.217 is given two choices -- he can comply
with either 91.217 (b) or (c).
3) "Part 21 and 23 do not apply to owner built aircraft with special
airworthiness certificates."
Basically true, but not specifically relevant to this discussion unless the
builder would try to use a non TSO'd altitude encoder by requesting approval
to deviate from TSO C-88b and its references in accordance with the
procedures of FAR Sec 21.609 -- not a trivial task.
Please let me know if I have not adequately described the situation.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
-----------------------------------------------
Subject: AeroElectric-List: Re: Questions on avionics
From: "rampil" <ira.rampil(at)gmail.com>
Again, back to 91.217 (b):
(b) Unless, as installed, that equipment was tested and calibrated to
transmit altitude data corresponding within 125 feet (on a 95 percent
probability basis) of the indicated or calibrated datum of the altimeter
normally used to maintain flight altitude, with that altimeter referenced to
29.92 inches of mercury for altitudes from sea level to the maximum
operating altitude of the aircraft; or
This is just the performance test. It says nothing about TSO.
Part 21 and 23 do not apply to owner built aircraft with special
airworthiness certificates
--------
Ira N224XS
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
Holes and temperature had nothing to do with it. Extract from:
http://www.alliedrubber.com/Gasket/SBRRubber.cfm.htm
Neoprene is known for its resistance to oil, gasoline, sunlight, ozone and oxidation;
however, there are other polymers that have better resistance to these
same elements. Neoprene's most important advantage is its ability to combine these
properties moderately into one all-purpose polymer.
Resistance to corrosive actions of chemicals is good. Neoprene exhibits resilience,
tensile strength, tear resistance and dynamic properties; abrasion resistance
and compression set properties.
COLOR Black
DURO 40,50,60,70,80
TENSILE900
ELONGATION300%
TEMP-20F to 170F
OIL RESIST Good
Nitrile's (Buna-N) resistance to the more aromatic distillates of petroleum is
better than neoprene, and it exhibits excellent resistance to mineral and vegetable
oils, but relatively poor resistance to the swelling action of oxygenated
solvents such as acetone and the ketones. Resistance to heat aging is good.
Nitrile exhibits good resilience, low permanent set, good abrasion resistance and
some ozone resistance. Tear resistance is inferior to natural rubber.
Nitrile accommodates applications where oils and heat are prevalent.
COLOR Black/ White
DURO 60
TENSILE300
ELONGATION900%
TEMP-20F to 170F
OIL RESIST. Good
SBR: Certain types of SBR offer improved wear resistance in tire treads while others
provide better low temperature flexibility. SBR has similar resistance to
solvents and chemicals as natural rubber and it can be successfully bonded to
a wide range of materials.
When exposed to petroleum derivatives, the performance of this rubber is inferior
to many other synthetics. Red SBR rubber is popular for use as a gasket in
low pressure applications such as washers and gaskets for the heating and plumbing
trades.
COLOR Red/Black
DURO 75
TENSILE400
ELONGATION150%
TEMP-29F to 170F
OIL RESIST. None [This should be a clue]
Summary. SBR should NEVER be used for grommets near petroleum vapors, oils or
solvents.
General advice: It is always a surprise when modern materials fail. Companies spend
a lot of money to prevent problems like this, and even materials "not recommended"
for an application usually don't fail quickly. But beware inexpensive
materials made for specific applications not-your-own. Surprises happen. Things
break.
"In times of rapid change, experience could be your worst enemy."
---Jean Paul Getty
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=177963#177963
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: pinout for Softcom ATC-P intercom?? |
> > In the mean time, if anyone has the documentation
> > covering any version of a Softcom product and could
> > either produce a good scan or loan it to me for scanning,
> > I'd be happy to add the data to the library.
>
>Bob,
>
>Attached are scans of a photocopy of a Softcomm intercom schematic.
>It's a bit hazy but quite readable if one prints it at full resolution
>and tapes both halves together.
>
>I've already sent a copy to the original requestor.
Thank's Joe,
I've worked on it a bit in Photoshop and enhanced the
readability a tad. It has been posted to:
http://www.aeroelectric.com/Installation_Data/ATC-2P_Schematic.gif
Bob . . .
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
Another product that may be suitable is the plastic snap bushings such
as Spruce 04-05730. I never liked putting soft grommets from any source
in very thin metal.
Ken
Jeff Page wrote:
>
> Two of you both thought my grommet problem so absurd that it must be a
> prank.
> I wish that were true, but my T hangar is locked.
> They were exposed only to cold air, darkness, time and my installation.
> When I get to the hangar next, i will be taking a close look at all of
> them, to see if the ones remaining are partly torn, or if some of them
> are perfectly intact.
> I will also try to do some tests with some still in the box to see if I
> can tear them like that.
> Sure is weird though. We install grommets to protect the wires, so they
> should be tougher than the insulation.
>
> Jeff
>
>> Are you sure someone didn't cut them off, just to play a mind game with
>> you??
>>
>> Roger
>
>>> Just a guess but exposure to solvents could breakdown SBR. I cannot
>>> imagine that hole size alone is the issue.
>> I will chime in and comment.... This is really hard to believe they spli
>> t all by themselves. Are you sure someone didn't remove them and split t
>> hem with a razor and them drop them on the floor as a joke/ prank etc...
>>
>> Ben Haas
>
________________________________________________________________________________
| From: | D Fritz <dfritzj(at)yahoo.com> |
| Subject: | A Bit of Help, Please |
Stan,
I've been watching the development of Landing Lights over the last several years
as I build my Velocity. It used to be the cost of flying was enough to rationalize
keeping on building rather than actually finishing and taking the plane
out of the garage. Now it seems the advances in LED technology may be a new
way to rationalize! I'm curious if you've lit these up yet and can give us an
impression of how well they light compared to the other technologies out there
(filament, halogen, HID, etc.). Can you give us a quick user report? What
model are you using?
Thanks,
Dan
---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.
________________________________________________________________________________
| From: | "Dennis Johnson" <pinetownd(at)volcano.net> |
Hi Jeff,
I just can't imagine any circumstance where expansion/contraction could
cut a grommet completely in two. It might cut a grommet mostly in half,
but it seems like at some point as the grommet failed, the pressure on
it would be released and the grommet would stop failing and remain in
place. To find them lying on the floor, cut in half, is really
baffling. But I'm interested in hearing your conclusion, because I
always enjoy learning something new.
I wonder if the grommets were manufactured by bonding two pieces
together and the grommets failed by splitting apart on the bond line due
to a manufacturing defect?
Dennis Johnson
________________________________________________________________________________
| From: | N81JG <n81jg(at)aol.com> |
| Subject: | Garmin 250XL problem |
I have a VariEze with a Garmin 250XL GPS/COM. I accidentally shut off the master
while flying and because of my B&C 8 amp. permanent magnet alternator I continued
to feed power to the buss until I rolled out on landing. At that point the
instruments showed intermittent low voltage and were flickering and cutting
out. I discover the reason and turned the master back on. The next flight my
250XL began to flick off and back on in a split second several times at regular
4-5 min. intervals. It continued to work fine as it was on, but the GPS had
to reboot each time. It appears that I have damaged some internal component with
the low voltage episode. Does anyone know if this can be fixed easily or am
I looking at a major circuit change-out?
John Greaves
VariEze N81JG
Redding, CA
________________________________________________________________________________
| From: | "Tim Andres" <tim2542(at)sbcglobal.net> |
| Subject: | Garmin 250XL problem |
Hi John, Tim In cottonwood (Cozy builder.) Those radios have two electrical
feeds. I would pull the radio from the tray, find the pinout from the
install manual or elsewhere and then check for continuous power to each feed
as you move the harness around from the back side. I think I have a pinout
for the 300 XL in a hanger near you if you need it. I bet they are the same.
Also check the ground wire the same way. There is also a chance it's the
connector in the tray and you can clean those contacts with electrical
cleaner while you have it out. I'm no expert but I am pretty handy with this
sort of thing, and I'm off the next 3 days if you need any help. I'm just
guessing but I bet the radio is fine and it's in the tray connector or the
install somewhere, probably just a coincidence it came up after your last
flight.
Tim Andres
347 6138
_____
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of N81JG
Sent: Sunday, April 20, 2008 10:34 AM
Subject: AeroElectric-List: Garmin 250XL problem
I have a VariEze with a Garmin 250XL GPS/COM. I accidentally shut off the
master while flying and because of my B&C 8 amp. permanent magnet alternator
I continued to feed power to the buss until I rolled out on landing. At that
point the instruments showed intermittent low voltage and were flickering
and cutting out. I discover the reason and turned the master back on. The
next flight my 250XL began to flick off and back on in a split second
several times at regular 4-5 min. intervals. It continued to work fine as it
was on, but the GPS had to reboot each time. It appears that I have damaged
some internal component with the low voltage episode. Does anyone know if
this can be fixed easily or am I looking at a major circuit change-out?
John Greaves
VariEze N81JG
Redding, CA
_____
Get the MapQuest <http://www.mapquest.com/toolbar?NCID=mpqmap00030000000003>
Toolbar, Maps, Traffic, Directions & More!
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Dual alternator single shunt |
My Murphy Rebel is going together with a slightly modified dual alternator,
single battery Z-12 design. The primary alternator is the Jabiru 3300's
integral 20A PM alternator. The second, backup only alternator is a manually
switched B&C SD-20S. Except during very brief, momentary, preflight test
switching perhaps, the two alternators will probably never be ON
simultaneously.
Due to various challenges, I'd like to use just one ammeter shunt to read
output from both alternators, whichever is in use. However, that would
require the shunt to be located downstream of the two independent
ANL/fusible links, instead of upstream from the ANL/fusible links as shown
in Z-12.
It appears to me there would be no significant electrical difference in
having a single shunt downstream from the two ANL/fusible's compared to two
shunts being upstream, as long as the single downstream shunt is big enough
to take the output of both alternators if need be. Is that correct, or am I
missing something?
Ron
Murphy Rebel / Jabiru 3300
http://n254mr.com
"wiring the panel and FWF"
________________________________________________________________________________
| From: | MartinErni(at)aol.com |
| Subject: | Re: Dual alternator single shunt |
Ron,
I found it easier to place the shunt next to my common ground block that
goes to both batteries.
Earnest
In a message dated 4/20/2008 8:06:31 P.M. Eastern Daylight Time,
rshannon(at)CRUZCOM.COM writes:
My Murphy Rebel is going together with a slightly modified dual alternator,
single battery Z-12 design. The primary alternator is the Jabiru 3300's
integral 20A PM alternator. The second, backup only alternator is a manually
switched B&C SD-20S. Except during very brief, momentary, preflight test
switching perhaps, the two alternators will probably never be ON simultaneously.
Due to various challenges, I'd like to use just one ammeter shunt to read
output from both alternators, whichever is in use. However, that would require
the shunt to be located downstream of the two independent ANL/fusible links,
instead of upstream from the ANL/fusible links as shown in Z-12.
It appears to me there would be no significant electrical difference in
having a single shunt downstream from the two ANL/fusible's compared to two
shunts being upstream, as long as the single downstream shunt is big enough to
take the output of both alternators if need be. Is that correct, or am I missing
something?
Ron
Murphy Rebel / Jabiru 3300
_http://n254mr.com_ (http://n254mr.com/)
"wiring the panel and FWF"
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Dual alternator single shunt |
Thanks for the input. Physically, that's roughly where my shunt will be too,
on the FW about 8" or less from the FW ground stud, contactors, battery,
etc. (Only one battery here.) I'm just trolling the group wisdom to confirm
I'm not creating some unanticipated electrical risk with a single shunt
downstream from the two alternators' ANLs.
Ron
On Sun, Apr 20, 2008 at 5:09 PM, wrote:
> Ron,
> I found it easier to place the shunt next to my common ground block
> that goes to both batteries.
> Earnest
>
________________________________________________________________________________
| From: | "Lee Logan" <leeloganster(at)gmail.com> |
| Subject: | Re: AeroElectric-List Digest: 10 Msgs - 04/19/08 |
I am in the process of completing the wiring design/effort on my homebuilt
F1 Rocket and am "planning" on not using a battery bus, just a main and
endurance buses. I'm using Z-13/8 (conventional mags), but don't see a need
for a "keep alive" circuit with my avionics suite (not do I need power for
an electronic ignition system). I see that other builders have put all
sorts of things on their battery bus, such as flaps, clocks, etc. Since I
may be missing something here, I'm asking: What does the "List" think ought
to be on a "modern" battery bus and what rationale is commonly used to
justify those selections, please...
Regards,
Lee...
________________________________________________________________________________
| From: | "Dale Ensing" <densing(at)carolina.rr.com> |
| Subject: | Re: AeroElectric-List Digest: 10 Msgs - 04/19/08 |
I have a small battery bus for the 'keep alive' for the clock in my
engine monitor and for a 12 voltv cig. lighter outlet which I use for
the Battery Minder to maintain the battery in the hangar and accesories
like my XM radio when flying. Happy with that set up.
Dale Ensing
----- Original Message -----
From: Lee Logan
To: aeroelectric-list(at)matronics.com
Sent: Sunday, April 20, 2008 8:58 PM
Subject: AeroElectric-List: Re: AeroElectric-List Digest: 10 Msgs -
04/19/08
I am in the process of completing the wiring design/effort on my
homebuilt F1 Rocket and am "planning" on not using a battery bus, just a
main and endurance buses. I'm using Z-13/8 (conventional mags), but
don't see a need for a "keep alive" circuit with my avionics suite (not
do I need power for an electronic ignition system). I see that other
builders have put all sorts of things on their battery bus, such as
flaps, clocks, etc. Since I may be missing something here, I'm asking:
What does the "List" think ought to be on a "modern" battery bus and
what rationale is commonly used to justify those selections, please...
Regards,
Lee...
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: AeroElectric-List Digest: 10 Msgs - 04/19/08 |
My blade fuse-style battery bus has these fused circuits:
1) cabin dome lights
2) the N/O oil pressure switch which feeds the Hobbes meter
3) E-Bus alternate feed fuse
4) low amperage (15A) ground power which goes to the battery, of course
5) power for the over-voltage panel light so if everything suddenly goes
dark due to an over voltage trip, I'll still have a clue what happened.
Any of those fuses could be handled by an inline fuse. I prefer having them
securely mounted and organized on a fuse block where I can easily get to
them. I have one more slot in the block, and will probably find something
else to go there.
Ron
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | why a battery bus? [was: Digest....] |
Correction: There is no # 5. The alternator warn light is on the main bus.
Don't know what/if I was thinking.
My blade fuse-style battery bus has these fused circuits:
>
> 1) cabin dome lights
> 2) the N/O oil pressure switch which feeds the Hobbes meter
> 3) E-Bus alternate feed fuse
> 4) low amperage (15A) ground power which goes to the battery, of course
> 5) power for the over-voltage panel light so if everything suddenly goes
> dark due to an over voltage trip, I'll still have a clue what happened.
>
> Any of those fuses could be handled by an inline fuse. I prefer having
> them securely mounted and organized on a fuse block where I can easily get
> to them. I have one more slot in the block, and will probably find something
> else to go there.
>
> Ron
>
>
________________________________________________________________________________
| From: | Kevin Horton <khorton01(at)rogers.com> |
| Subject: | Re: AeroElectric-List Digest: 10 Msgs - 04/19/08 |
On 21 Apr 2008, at 01:58, Lee Logan wrote:
> I am in the process of completing the wiring design/effort on my
> homebuilt F1 Rocket and am "planning" on not using a battery bus,
> just a main and endurance buses. I'm using Z-13/8 (conventional
> mags), but don't see a need for a "keep alive" circuit with my
> avionics suite (not do I need power for an electronic ignition
> system). I see that other builders have put all sorts of things on
> their battery bus, such as flaps, clocks, etc. Since I may be
> missing something here, I'm asking: What does the "List" think
> ought to be on a "modern" battery bus and what rationale is
> commonly used to justify those selections, please...
I'd put anything that needed "keep alive" power, and anything that
you absolutely need to have running if you kill the battery master
and alternator following a "smoke in the cockpit" event. In my case,
I will fly IFR, so I need something to help me keep the wings level -
I put my turn and bank on the battery bus. You want as little as
possible on the battery bus, to maximize the chance that you can stop
the smoke by killing the electrics.
Given your situation, I agree that there may be no need for a battery
bus.
--
Kevin Horton
RV-8 (FInal Assembly)
Ottawa, Canada
http://www.kilohotel.com/rv8
________________________________________________________________________________
| From: | Kevin Horton <khorton01(at)rogers.com> |
I would expect proper aviation grommets to be OK, as long as they
were installed in proper sized holes. These grommets are made to
military specifications, and should have been well tested in aviation
environments. The ones with narrow grooves are certainly intended to
be installed in thin sheet.
Putting a grommet in an undersized hole (as the original poster did)
is using the grommet in a way that the designer never intended. In
this case, all the design work and testing that the manufacturer did
is is no longer relevant, as is the previous service history. You
now are on your own, and have to do your own testing to establish an
envelope of conditions under which the grommet functions properly.
The original poster has learned that one type of non-aviation
grommet, installed in an undersized hole, is not appropriate for
aviation use.
--
Kevin Horton
On 20 Apr 2008, at 14:45, Ken wrote:
>
> Another product that may be suitable is the plastic snap bushings
> such as Spruce 04-05730. I never liked putting soft grommets from
> any source in very thin metal.
> Ken
>
> Jeff Page wrote:
>> Two of you both thought my grommet problem so absurd that it must
>> be a prank.
>> I wish that were true, but my T hangar is locked.
>> They were exposed only to cold air, darkness, time and my
>> installation.
>> When I get to the hangar next, i will be taking a close look at
>> all of them, to see if the ones remaining are partly torn, or if
>> some of them are perfectly intact.
>> I will also try to do some tests with some still in the box to see
>> if I can tear them like that.
>> Sure is weird though. We install grommets to protect the wires,
>> so they should be tougher than the insulation.
>> Jeff
>>> Are you sure someone didn't cut them off, just to play a mind
>>> game with
>>> you??
>>>
>>> Roger
>>>> Just a guess but exposure to solvents could breakdown SBR. I
>>>> cannot
>>>> imagine that hole size alone is the issue.
>>> I will chime in and comment.... This is really hard to believe
>>> they spli
>>> t all by themselves. Are you sure someone didn't remove them and
>>> split t
>>> hem with a razor and them drop them on the floor as a joke/ prank
>>> etc...
>>>
>>> Ben Haas
>
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Encoding Altimeter |
4/20/2008
Hello Anonymous, You wrote:
1) "You seem to be saying that the only practical way to meet the
requirements is to use a TSO'd source for the altitude information the
transponder is transmitting."
That is close. Here is how I would phrase it: "At present the only practical
way to be in compliance with FAR Section 91.217, Data Correspondence Between
Automatically Reported Pressure Altitude Data and the Pilot's Altitude
Reference, is to use a TSO'd equipment source for the altitude information
the transponder is transmitting."
2) "That, of course, would eliminate valuable functionality of many
non-TSO'd electronic EFISs including the serial output to the transponder."
Specifically, the serial altitude data output to the transponder from a non
TSO'd altitude encoder within an EFIS would not, at present, be in
compliance
with either 91.217 (b) or (c).
3) "Clearly, that isn't happening in the real world. These are selling
well."
Correct.
4) "Are you against that?"
Not at all. Here are my positions:
A) People should make informed decisions.
B) If I can provide accurate information to people that will permit them to
make informed decisions I should do so.
C) The decisions that those people make, after I have given them the best
information that I have available, is theirs to make, not mine. The risks
that they chose to take, or not take, are theirs, not mine.
D) Most of the EFIS available to the amateur built community represent a
significant improvement in performance, reliability, and safety over
previously available flight instrument technology.
E) Most of the EFIS available to the homebuilt community contain a non-TSO'd
altitude encoder that is superior in performance, reliability, granularity,
and accuracy over altitude encoding equipment that was manufactured to
versions of TSO-C88 prior to TSO-C88b.
F) Amateur built experimental aircraft have flown thousands of hours using
EFIS with non-TSO'd altitude encoders feeding their transponders with no
apparent problems.
G) Hundreds of amateur built experimental airplanes are under construction
using EFIS containing non-TSO'd altitude encoders.
H) The FAA should recognize and accept the real world conditions described
in D, E, F, and G above.
I) The best way for the FAA to accept the real world conditions described in
D, E, F, and G above is to interpret the tests required by FAR Secs 91.411
and 91.413 (as appropriate) as fulfilling the requirements of FAR Sec 91.217
(b).
J) My initial attempts to accomplish H and I above with FAA HQ were met with
resistance and I ceased activity in this regard.**
K) If the FAA, and the people / entities who perform the tests required by
91.411 / 91.413, decided that every non-TSO'd altitude encoder in an EFIS
was not airworthy because it did not meet the requirements of either 91.217
(b) or (c) this decision would be a serious blow to the amateur built
community.**
L) I do not proactively broadcast the information in K above, but if someone
asks a specific question on this issue or posts a position that I know to be
in error I revert to my positions A and B above.
M) I am open to improvements or changes in my positions.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
**PS: The FAA decision makers who perpetrated the recent fiasco involving
hundreds of airline flights being canceled and thousands of people being
stranded over the issue of the exact spacing of electrical wire cable ties
in the landing gear wheel wells of airline aircraft are capable of such
thinking and actions.
------------------------------------------------------------
----- Original Message -----
From: Anonymous
Sent: Sunday, April 20, 2008 9:20 AM
Subject: Encoding Altimeter
> OC,
>
> I don't understand what you are trying to say with your posts
> to
> the AeroElectric List. You seem to be saying that the only practical way
> to
> meet the requirements is to use a TSO'd source for the altitude
> information
> the transponder is transmitting. That, of course, would eliminate
> valuable
> functionality of many non-TSO'd electronic EFISs including the serial
> output
> to the transponder. Clearly, that isn't happening in the real world.
> These
> are selling well. Are you against that?
Anonymous
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: AeroElectric-List Digest: 10 Msgs - 04/19/08 |
I also use a battery bus cigarette lighter receptacle for several
things. Programming handheld gps, blowing up air mattresses, powering a
small inverter for a soldering iron, dremel tool etc. It was really
installed to power handheld devices in flight after everything else was
shut off. I also put a switch beside the receptacle to kill it which is
handier than unplugging stuff sometimes. LED dome lights are also on
that circuit. I have additional cig. lighter receptacles that get power
through the batt master contactor.
Ken
Dale Ensing wrote:
> I have a small battery bus for the 'keep alive' for the clock in my
> engine monitor and for a 12 voltv cig. lighter outlet which I use for
> the Battery Minder to maintain the battery in the hangar and accesories
> like my XM radio when flying. Happy with that set up.
> Dale Ensing
>
> ----- Original Message -----
> *From:* Lee Logan
> *To:* aeroelectric-list(at)matronics.com
>
> *Sent:* Sunday, April 20, 2008 8:58 PM
> *Subject:* AeroElectric-List: Re: AeroElectric-List Digest: 10 Msgs
> - 04/19/08
>
> I am in the process of completing the wiring design/effort on my
> homebuilt F1 Rocket and am "planning" on not using a battery bus,
> just a main and endurance buses. I'm using Z-13/8 (conventional
> mags), but don't see a need for a "keep alive" circuit with my
> avionics suite (not do I need power for an electronic ignition
> system). I see that other builders have put all sorts of things on
> their battery bus, such as flaps, clocks, etc. Since I may be
> missing something here, I'm asking: What does the "List" think
> ought to be on a "modern" battery bus and what rationale is commonly
> used to justify those selections, please...
>
> Regards,
>
> Lee...
________________________________________________________________________________
| From: | "David & Elaine Lamphere" <lamphere(at)vabb.com> |
| Subject: | Re: Dual alternator single shunt |
Will this position of the shunt cause any problems when the engine
starter is engaged?? (as in peg the meter)
Dave
----- Original Message -----
From: Ron Shannon
To: aeroelectric-list(at)matronics.com
Sent: Sunday, April 20, 2008 8:47 PM
Subject: Re: AeroElectric-List: Dual alternator single shunt
Thanks for the input. Physically, that's roughly where my shunt will
be too, on the FW about 8" or less from the FW ground stud, contactors,
battery, etc. (Only one battery here.) I'm just trolling the group
wisdom to confirm I'm not creating some unanticipated electrical risk
with a single shunt downstream from the two alternators' ANLs.
Ron
On Sun, Apr 20, 2008 at 5:09 PM, wrote:
Ron,
I found it easier to place the shunt next to my common ground
block that goes to both batteries.
Earnest
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: LED Landing Lights |
>Stan,
>I've been watching the development of Landing Lights over the last several
>years as I build my Velocity. It used to be the cost of flying was enough
>to rationalize keeping on building rather than actually finishing and
>taking the plane out of the garage. Now it seems the advances in LED
>technology may be a new way to rationalize! I'm curious if you've lit
>these up yet and can give us an impression of how well they light compared
>to the other technologies out there (filament, halogen, HID, etc.). Can
>you give us a quick user report? What model are you using?
>
>Thanks,
>Dan
I'm not at liberty to speak to details but know that
the TC aircraft guys are presently evaluating LED
landing and taxi light products in a right-left
comparison of new and old technologies on existing
high-performance aircraft. When the go/no-go
decisions are made and they're ready to share
their findings, I'll let you all know.
At first blush, it's a no-brainer. Incandescent
lamps will soon be a thing of the past.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Garmin 250XL problem |
>I have a VariEze with a Garmin 250XL GPS/COM. I accidentally shut off the
>master while flying and because of my B&C 8 amp. permanent magnet
>alternator I continued to feed power to the buss until I rolled out on
>landing. At that point the instruments showed intermittent low voltage and
>were flickering and cutting out. I discover the reason and turned the
>master back on. The next flight my 250XL began to flick off and back on in
>a split second several times at regular 4-5 min. intervals. It continued
>to work fine as it was on, but the GPS had to reboot each time. It appears
>that I have damaged some internal component with the low voltage episode.
>Does anyone know if this can be fixed easily or am I looking at a major
>circuit change-out?
I can't speak to the potential for damage to your
accessories but I can suggest a review of your system
architecture that allows operator mis-positioning of
switches to produce an alternator-only powering of
the bus.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | MartinErni(at)aol.com |
| Subject: | Re: Dual alternator single shunt |
I put the starter ground on the same side of the shunt as the battery
grounds. All other grounds attach to the other side of the shunt, so the answer
is
"no".
Earnest
In a message dated 4/21/2008 8:36:06 A.M. Eastern Daylight Time,
lamphere(at)vabb.com writes:
Will this position of the shunt cause any problems when the engine starter
is engaged?? (as in peg the meter)
Dave
----- Original Message -----
From: _Ron Shannon_ (mailto:rshannon(at)cruzcom.com)
(mailto:aeroelectric-list(at)matronics.com)
Sent: Sunday, April 20, 2008 8:47 PM
Subject: Re: AeroElectric-List: Dual alternator single shunt
Thanks for the input. Physically, that's roughly where my shunt will be too,
on the FW about 8" or less from the FW ground stud, contactors, battery,
etc. (Only one battery here.) I'm just trolling the group wisdom to confirm I'm
not creating some unanticipated electrical risk with a single shunt
downstream from the two alternators' ANLs.
Ron
On Sun, Apr 20, 2008 at 5:09 PM, <_MartinErni(at)aol.com_
(mailto:MartinErni(at)aol.com) > wrote:
Ron,
I found it easier to place the shunt next to my common ground block that
goes to both batteries.
Earnest
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
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
| Subject: | Re: LED Landing Lights |
JFTR...
Whelen shows LED landing lights in their current catalog...
Thanks!
Bill Denton
bdenton(at)bdenton.com
-----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: Monday, April 21, 2008 8:32 AM
Subject: AeroElectric-List: Re: LED Landing Lights
>Stan,
>I've been watching the development of Landing Lights over the last several
>years as I build my Velocity. It used to be the cost of flying was enough
>to rationalize keeping on building rather than actually finishing and
>taking the plane out of the garage. Now it seems the advances in LED
>technology may be a new way to rationalize! I'm curious if you've lit
>these up yet and can give us an impression of how well they light compared
>to the other technologies out there (filament, halogen, HID, etc.). Can
>you give us a quick user report? What model are you using?
>
>Thanks,
>Dan
I'm not at liberty to speak to details but know that
the TC aircraft guys are presently evaluating LED
landing and taxi light products in a right-left
comparison of new and old technologies on existing
high-performance aircraft. When the go/no-go
decisions are made and they're ready to share
their findings, I'll let you all know.
At first blush, it's a no-brainer. Incandescent
lamps will soon be a thing of the past.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | Glen Matejcek <aerobubba(at)earthlink.net> |
| Subject: | Re: Non-tso altitude encoder, was Questions on avionics |
OC-
Thanks for answering the question before I could ask it!
Glen Matejcek
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: ELT Antenna for Fiberglass aircraft |
Good Morning Bruce,
Obsolete maybe, but I believe they will still meet federal requirements.
Is that not true?
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/18/2008 2:20:30 P.M. Central Daylight Time,
Bruce(at)glasair.org writes:
--> AeroElectric-List message posted by: "Bruce Gray"
I could be wrong but I don't think that dipole antennas are around for 406
MHTZ ELT's yet. They exist for 121.5 ELT's but they will be obsolete next
year.
Bruce
www.Glasair.org
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Dual alternator single shunt |
Not sure I understand this point, Earnest. Is your shunt wired differently
than shown in Z-12, or the same?
Looking at Z-12, basically my proposal for a single shunt instead of two
would mean that the downstream side of both ANL/fusible links would be
connected to the shunt, instead of to the battery side of the starter
contactor. The other side of the shunt would then connect to the battery
side of the starter contactor. I don't see meaningful electrical difference
between that and the dual shunt circuit in Z-12. (Except obviously, with
just one "joint" shunt you can't discriminate between readings for the two
different alternators if they were ever run simultaneously, which mine won't
be.)
Ron
On Mon, Apr 21, 2008 at 7:01 AM, wrote:
> I put the starter ground on the same side of the shunt as the battery
> grounds. All other grounds attach to the other side of the shunt, so the
> answer is "no".
> Earnest
>
________________________________________________________________________________
| From: | cecilth(at)juno.com |
FOR SALE, RV6A 99% complete Except for engine. I had a heart attack, lost
medical. I completed the plane including a Chev V6 Vortec engine. I will
keep the engine for insurance reasons.
See attachment
________________________________________________________________________________
| From: | MartinErni(at)aol.com |
| Subject: | Re: Dual alternator single shunt |
I don't have z-12 handy so I couldn't say. Basically my starter ground
bypasses the shunt.
In a message dated 4/21/2008 1:31:38 P.M. Eastern Daylight Time,
rshannon(at)CRUZCOM.COM writes:
Not sure I understand this point, Earnest. Is your shunt wired differently
than shown in Z-12, or the same?
Looking at Z-12, basically my proposal for a single shunt instead of two
would mean that the downstream side of both ANL/fusible links would be connected
to the shunt, instead of to the battery side of the starter contactor. The
other side of the shunt would then connect to the battery side of the starter
contactor. I don't see meaningful electrical difference between that and the
dual shunt circuit in Z-12. (Except obviously, with just one "joint" shunt
you can't discriminate between readings for the two different alternators if
they were ever run simultaneously, which mine won't be.)
Ron
On Mon, Apr 21, 2008 at 7:01 AM, <_MartinErni(at)aol.com_
(mailto:MartinErni(at)aol.com) > wrote:
I put the starter ground on the same side of the shunt as the battery
grounds. All other grounds attach to the other side of the shunt, so the answer
is
"no".
Earnest
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Dual alternator single shunt |
>My Murphy Rebel is going together with a slightly modified dual
>alternator, single battery Z-12 design. The primary alternator is the
>Jabiru 3300's integral 20A PM alternator. The second, backup only
>alternator is a manually switched B&C SD-20S. Except during very brief,
>momentary, preflight test switching perhaps, the two alternators will
>probably never be ON simultaneously.
>
>Due to various challenges, I'd like to use just one ammeter shunt to read
>output from both alternators, whichever is in use. However, that would
>require the shunt to be located downstream of the two independent
>ANL/fusible links, instead of upstream from the ANL/fusible links as shown
>in Z-12.
That' fine . . . .
>It appears to me there would be no significant electrical difference in
>having a single shunt downstream from the two ANL/fusible's compared to
>two shunts being upstream, as long as the single downstream shunt is big
>enough to take the output of both alternators if need be. Is that correct,
>or am I missing something?
That's correct.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: AeroElectric-List Digest: 10 Msgs - 04/19/08 |
>I am in the process of completing the wiring design/effort on my homebuilt
>F1 Rocket and am "planning" on not using a battery bus, just a main and
>endurance buses. I'm using Z-13/8 (conventional mags), but don't see a
>need for a "keep alive" circuit with my avionics suite (not do I need
>power for an electronic ignition system). I see that other builders have
>put all sorts of things on their battery bus, such as flaps, clocks,
>etc. Since I may be missing something here, I'm asking: What does the
>"List" think ought to be on a "modern" battery bus and what rationale is
>commonly used to justify those selections, please...
What items do you want to run without having the battery
contactor closed? Unless you have an electrically dependent
engine, don't want courtesy lights, electric clocks, hour
meter that runs on oil pressure switch even if the master is
off . . . then perhaps you don't need a battery bus. Its
easy to add if you decide it's needed later.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
>My blade fuse-style battery bus has these fused circuits:
>
>1) cabin dome lights
>2) the N/O oil pressure switch which feeds the Hobbes meter
>3) E-Bus alternate feed fuse
>4) low amperage (15A) ground power which goes to the battery, of course
Good . . .
>5) power for the over-voltage panel light so if everything suddenly goes
>dark due to an over voltage trip, I'll still have a clue what happened.
What item of equipment provides an ov trip indication?
What keeps this lead from draining the battery if it's
not on a charger?
>Any of those fuses could be handled by an inline fuse. I prefer having
>them securely mounted and organized on a fuse block where I can easily get
>to them. I have one more slot in the block, and will probably find
>something else to go there.
Sounds like a well considered and implemented
battery bus architecture.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Dual alternator single shunt |
>Will this position of the shunt cause any problems when the engine starter
>is engaged?? (as in peg the meter)
No . . .
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Dual alternator single shunt |
>I put the starter ground on the same side of the shunt as the battery
>grounds. All other grounds attach to the other side of the shunt, so the
>answer is "no".
>Earnest
???? I think the question was about having two alternator
output leads share a common shunt where they feed the bus.
Contrary to a suggestion in the 'Connection about ground-side
shunts, it's not a good idea and will be eliminated in
Revision 12.
Bob . . .
________________________________________________________________________________
| From: | MartinErni(at)aol.com |
| Subject: | Re: Dual alternator single shunt |
Which is not a good idea "ground-side shunts or 2 alt leads sharing a common
shunt"? Could you elaborate?
Earnest
In a message dated 4/21/2008 9:45:45 P.M. Eastern Daylight Time,
nuckolls.bob(at)cox.net writes:
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>I put the starter ground on the same side of the shunt as the battery
>grounds. All other grounds attach to the other side of the shunt, so the
>answer is "no".
>Earnest
???? I think the question was about having two alternator
output leads share a common shunt where they feed the bus.
Contrary to a suggestion in the 'Connection about ground-side
shunts, it's not a good idea and will be eliminated in
Revision 12.
Bob . . .
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "David & Elaine Lamphere" <lamphere(at)vabb.com> |
| Subject: | Re: Dual alternator single shunt |
I just have to ask ....
If you use a shunt that "sees" all current flowing from the battery and the
starter draws 200a, doesn't that hit the 50ma ammeter (if using a 40a shunt)
with 250ma?? Doesn't seem like that would do the ammeter any good...
I must be missing something about this... sorry..
Dave
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
Sent: Monday, April 21, 2008 9:39 PM
Subject: Re: AeroElectric-List: Dual alternator single shunt
>
>
>
>>Will this position of the shunt cause any problems when the engine starter
>>is engaged?? (as in peg the meter)
>
> No . . .
>
>
> Bob . . .
>
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Dual alternator single shunt |
Take a look at Z-12. As is the case in most all of Bob's schematics (I
think) the shunt is in series with the alternator output, which connects to
the upstream side of the starter contactor. The starter motor current goes
through the starter contactor. That heavy current does not split off to the
side, through the alternator. In that position the shunt senses the output
of the alternator.
Ron
On Mon, Apr 21, 2008 at 7:58 PM, David & Elaine Lamphere
wrote:
> lamphere(at)vabb.com>
>
> I just have to ask ....
>
> If you use a shunt that "sees" all current flowing from the battery and
> the starter draws 200a, doesn't that hit the 50ma ammeter (if using a 40a
> shunt) with 250ma?? Doesn't seem like that would do the ammeter any good...
>
> I must be missing something about this... sorry..
>
> Dave
>
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
>
>
> My blade fuse-style battery bus has these fused circuits:
> >
> > 1) cabin dome lights
> > 2) the N/O oil pressure switch which feeds the Hobbes meter
> > 3) E-Bus alternate feed fuse
> > 4) low amperage (15A) ground power which goes to the battery, of course
> >
>
> Good . . .
>
> 5) power for the over-voltage panel light so if everything suddenly goes
> > dark due to an over voltage trip, I'll still have a clue what happened.
> >
>
> What item of equipment provides an ov trip indication?
> What keeps this lead from draining the battery if it's
> not on a charger?
I later corrected my (silly) statement that I had the OV warn light on the
battery bus (#5 above) in a later post, where i changed the subject from
"Digest..." to "why a battery bus" so it would make a little more sense (the
subject, not my error!) When I listed OV warn, I must have been suffering
from some sort of acute brain fade, or worse, I guess. My alternator warn
light is powered through the main bus, of course.
>
>
> Any of those fuses could be handled by an inline fuse. I prefer having
> > them securely mounted and organized on a fuse block where I can easily get
> > to them. I have one more slot in the block, and will probably find something
> > else to go there.
> >
>
> Sounds like a well considered and implemented
> battery bus architecture.
>
> Bob . . .
At least as corrected. Thanks.
Ron
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Pinout for Softcom ATC-P and Website Maintenance |
>On 04/20/2008 05:59 Robert L. Nuckolls, III wrote:
>
> > I've worked on it a bit in Photoshop and enhanced the
> > readability a tad. It has been posted to:
> >
> > http://www.aeroelectric.com/Installation_Data/ATC-2P_Schematic.gif
>
>
>Very good, Bob. I'm sure members of the community will be grateful for
>it, as I have been for other materials you've provided over the years.
>
>Alas, the URL for the schematic (above) gives a "403 error". Perhaps
>the fix is as simple as giving the file read permissions for everyone.
>
>Best,
>Joe (K7JD)
>http://www.mail2600.com/Airplane
Thanks for the head's up on it Joe . . . your hypothesis
was correct. I didn't set the permissions after uploading.
On the topic of website maintenance, what started out
many moons ago as an eclectic collection of occasional
tidbits interesting to the OBAM aviation community to a rather
large body of work.
It's become so large that I'm having trouble keeping track
of what's posted where and why. A couple of weeks ago I
began a reorganization effort that will include sorting
of information into categories and a comprehensive linked
table of contents that will aid both the manager (me) and
the readers (you folks) in accessing what's available.
I think I've got a couple more days worth of work to go
but it's shaping up nicely. When the new organization is
posted, I'll have to rely on all of you good folks to
sift the sands of reorganization and letting me know
where a link or permission didn't get handled properly.
One example of the "new look" is already posted
at:
http://aeroelectric.com/Mfgr_Data.html
I have similar index pages being crafted for all
the articles.
On the topic of manufacturer's data, if any of you
possess operation, installation and/or maintenance
data on various bits of hardware that you can scan
(preferably into pdf files) and forward to me, I'll
have a better place to post such items and support
the efforts of our brothers.
Finally, I'd like to re-enforce the notion that the
website is not intended to be the gospel according
to Bob Nuckolls but a gathering place for sharing
the best we know how to do. If any of you have a
process or technique that seems particularly elegant
and you would like to share it, please feel encouraged
to write it up, take photos, etc. and forward to me.
I'll help with editing, captioning, formating and
of course, getting it posted.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
| Subject: | Re: A Bit of Help, Please |
Bob,
Your analysis of my situation was dead on accurate. And your info was
invaluable.
I sincerely appreciate your response!
Stan Sutterfield
>Bob,
>Thanks for your robust reply. Very helpful.
>My intention is to prevent reverse current flow in certain conditions.
>I connected the zener diodes in line where needed and did a test of the
>system and the diodes did stop the reverse flow of current - as
>desired. My concern was that the selected diodes (RS INT4742A - RS part
>number 276-563) may not be robust enough to stop the 0.9 Amp current over
>the long term.
That's what I understood. I was mystified by the
use of a zener diode. These will "stop reverse flow"
only if the voltage remains below the rating
at which reverse flow is desired and expected . . .
in the case of the 1N4742, 12 volts.
The "ratings" numbers for these devices are
given in there reverse current flow mode of
operation where they dissipate higher power
for the same current flow. Since this package
is generally good for about 1W of dissipation,
their max reverse current should be limited to
about 1w/12v = 0.08 amps. The 0.02 amps you cited
was the "test current" at which the 12v regulation
accuracy was given . . . not the operating
current where the current is dissipation limited.
You're using these devices in their forward
conduction mode where voltage drop is not related
to the zener voltage rating of the device, i.e.
12v but the forward conduction rating which is on
the same order as the ordinary silicon diode
rectifier of about 0.8 volts. Here the same
dissipation limits apply . . . but to get 1w
of heat out of it in the forward mode, you can
now force 1.2a through the device. MUCH larger
than any of the reverse current ratings given
in the 1N4742 data sheet . . . because folks
are generally expect to use theses as reverse
current regulators, not forward current
power steering devices.
http://en.wikipedia.org/wiki/Zener_diode
This is why the 1N4742 didn't smoke during your
extended bench test . . . you were not using it
in the manner described in the data sheets hence
non-hazardous dissipated power at higher than "rated"
currents.
>I may as well insert the correct diodes now rather than redo the work at a
>later time. So, it sounds like I should change the diodes to another type
>or another rating. Correct? Perhaps the 1N5400 series would be best.
The significance of my earlier posting was that
mis-application of the zener as a power steering
device was marginally satisfactory given that
voltages in your system are expected to exceed
the 12v rating of the device whereupon some amount
of reverse current may flow under conditions where
you don't want it to happen. If you picked a zener
that was larger, say 16v or even higher, then
it could be expected to function as you intended
even if it wasn't exactly the right part for the
job.
The silicon rectifier also has a voltage rating
stated as a limit. See:
http://www.diodes.com/datasheets/ds28002.pdf
Note that these little critters are the same
physical size as the 1N4742 but have voltage
limits ranging from 50 to 1000v. Any of these
devices could be used in your application. I
suggested the 5400 series devices be considered
also:
http://www.diodes.com/datasheets/ds28007.pdf
These to are offered in the same ranges of
voltage limits as the 4000 series devices and
while electrically much larger than you need in
this particular case, there's no great transgression
in using such devices at much lower levels
than their rated limits.
In this case, I favor the 5400 series devices
for their mechanical robustness. Larger package,
larger leadwires, much easier to work with in
these situations and less likely to be damaged in
service due to handling.
I think you got sucked into the 12v zener
selection due to a mis-understanding of its
rating as being "appropriate" to your 14v
airplane. The problem was that zeners are
not intended for or generally used as reverse
power blocking devices. The silicon rectifiers
come with lots larger voltage LIMIT ratings
so while much larger than the system voltage
of your aircraft, they are not being mis-applied
by using say a 600v device in your 14v
airplane.
So yes, my recommendation is that you avail yourself
of Radio Shack's standard inventory and substitute
any one of the 5400 series devices for the 1N4742
in the application you've described.
Bob . . .
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
| Subject: | Re: LED Landing Lights |
Dan,
I'd be happy to give you my impressions on using LEDs for landing lights.
I've done a number of experiments over the past 2 years with various LEDs up
to 1W. There are now much larger wattage LEDs (3W, 5W) available that
provide greater illumination, so my info is a bit dated. The technology gains
in
the LED industry is literally changing daily.
I don't have all the technical data, but rather will tell you in layman's
terms what I've discovered.
In short, LEDs are not yet ready for prime time as landing lights - although
they are getting very close. Several applications of LED headlights are in
use in 2008 automobiles, but I have not witnessed the performance of those
lights. I do know they are using optics similar to projection-type lights to
focus the LED emissions in order to get suitable illumination. Whelen had
some 12 LED landing lights at Sun n Fun, but to get illumination close to
halogens, they have to narrowly focus the beam (10 degrees, I think) which means
you get little side illumination which is needed at night in order to have the
peripheral vision needed to recognize sink rate in the landing flare.
However, although not ready as landing lights, I believe LEDs are quite up to
the
task as taxi or recognition lights. Peripheral vision is not as critical when
taxiing and furthermore, LEDs can be used in a wider beam which does not
project as far.
I bought the AeroSun 800 LED lights and found them suitable only as
taxi/recognition lights. I don't intend to use them because they are heavy and
the
dimensions are twice as large as I can fit in my airplane. I bought the
Whelen Model 71125 LED light to use as taxi-recognition lights. I have a steady
on in one switch position and flashing (using Eric Jones' wig wag) in the
other position.
I believe that, at this time, LEDs are suitable for taxi illumination and
for recognition lights. As recognition lights, the square wave light emission
is easily recognized by the eye. The temperature of the light emission is
close to daylight (the yellow emission of halogen is easier to see in daylight
conditions), however the square wave pattern mitigates the tendency of the
light to blend into daylight.
I have a short report and photos of the AeroSun 800 lights on my web site at
_http://www.rv-8a.net/2008.htm_ (http://www.rv-8a.net/2008.htm) on 6 Mar
08. You can see the Whelen LEDs I bought on the same page if you scroll down
to 12 Apr 08.
I am completely sold on using LEDs for the position lights. Since they
simply have to radiate and not illuminate, LEDs are ideal for position lights.
I've been complaining at Whelen to bring out 12v LED position lights and they
finally did it. They consume only 0.25A, so three would be only 0.75A. I
strongly recommend using LEDs for position lights.
I believe you are wise to wait a bit longer to decide which LED light to
use. I am convinced that LEDs will be able to provide illumination suitable for
use as a landing light in the near future.
If you have additional questions, feel free to contact me offline.
Stan Sutterfield
_www.rv-8a.net_ (http://www.rv-8a.net)
Stan,
I've been watching the development of Landing Lights over the last several
years
as I build my Velocity. It used to be the cost of flying was enough to
rationalize
keeping on building rather than actually finishing and taking the plane
out of the garage. Now it seems the advances in LED technology may be a new
way to rationalize! I'm curious if you've lit these up yet and can give us
an
impression of how well they light compared to the other technologies out
there
(filament, halogen, HID, etc.). Can you give us a quick user report? What
model are you using?
Thanks,
Dan
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
Lee,
I'm not building in a battery bus either. I don't need it. The only thing
that needs a battery bus on my plane is a GPS antenna keep alive. With it,
the GPS locks on in 10 seconds. Without it, it locks on in 30 seconds.
Stan Sutterfield
I am in the process of completing the wiring design/effort on my homebuilt
F1 Rocket and am "planning" on not using a battery bus, just a main and
endurance buses. I'm using Z-13/8 (conventional mags), but don't see a need
for a "keep alive" circuit with my avionics suite (not do I need power for
an electronic ignition system). I see that other builders have put all
sorts of things on their battery bus, such as flaps, clocks, etc. Since I
may be missing something here, I'm asking: What does the "List" think ought
to be on a "modern" battery bus and what rationale is commonly used to
justify those selections, please...
Regards,
Lee...
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
Lee,
A slight correction. While I don't have a battery bus, I do have a fused
wire from the hot battery terminal that powers my dimmer-controlled interior
LED lights.
Stan Sutterfield
I am in the process of completing the wiring design/effort on my homebuilt
F1 Rocket and am "planning" on not using a battery bus, just a main and
endurance buses.
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: A Bit of Help, Please |
>Bob,
>Your analysis of my situation was dead on accurate. And your info was
>invaluable.
>I sincerely appreciate your response!
>Stan Sutterfield
My pleasure sir . . . it's what we do!
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: To battery bus or not to battery bus, that IS the |
question.
>Lee,
>A slight correction. While I don't have a battery bus, I do have a fused
>wire from the hot battery terminal that powers my dimmer-controlled
>interior LED lights.
>Stan Sutterfield
Aha! Obviously it's not a "bus" (distribution to
two or more loads) but it's still an always-hot
feed directly from the battery. Even the lowly
C-140 I used to fly a lot had sort-of-a battery
bus. There were two fuseholders on a bracket
right at the battery contactor that powered the
electric clock and the Hobbs meter.
Clearly, not everyone will need this feature in
their project but it's one of those things
easily added at some later time to support an
upgrade of system features (like sticking an SD-8
on Z11 to make it Z13 an SD-20 to make it a Z12).
The caveats are simple suggestions to be mindful
of crash safety (e.g. limiting protection sizes) and
failure mode effects analysis (e.g. driving electrically
dependent engines directly from hot battery sources)
for the purpose of achieving design goals.
Bob . . .
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Encoding Altimeter |
4/22/2008
Hello Bill, Thanks for your input. You wrote:
1) "OR...you could buy a Dynon ........."
Since the Dynon units do not contain a TSO'd altitude encoder operating the
Dynon unit alone to feed a transponder in flight would presently leave one
in violation of FAR Sec 91.217 (as interpreted by FAA HQ). There are two
ways to approach this condition:
A) Purchase and install a separate TSO'd altitude encoder and use that
encoder to feed the aircraft's transponder.
B) Decide that violation of 91.217 is an acceptable risk and feed the
transponder from the non TSO'd altitude encoder contained in the Dynon unit.
2) ".....and save even more during the IFR recertification check."
My local avionics shop charges a flat fee for the FAR Sections 91.411 and
91.413 required testing. This fee has been the same no matter whether I do
the labor of removing and reinstalling the altimeter and TSO'd altitude
encoder, for bench testing and any adjustments needed prior to the airplane
side testing, or they do that labor. (By the way, four years ago that flat
fee was $150, now it is $300.)
3) "........the avionics shops actually prefer the Dynon due to their
accuracy and simplicity."
I hope that the avionics shops continue this practice without any regard for
what FAR Sec 91.217 says.
4) ".......the avionics shops actually prefer the Dynon due to their
accuracy and simplicity."
I wonder about the complexity of removing and reinstalling an EFIS from the
airplane compared to the complexity of removing and reinstalling an
altimeter and separate TSO'd altitude encoder should any bench testing and
adjusting be needed.
A) Maybe EFIS removal and reinstallation is no big deal, but I envision a
bunch of connections, particularly if it is the type of EFIS that also
includes displaying engine performance parameters.
B) Maybe the EFIS's have no means of local avionics shop adjustment.
C) Maybe the EFIS's would never need adjustment.
D) What has been the experience of EFIS operators that have actually been
through FAR 91.411 and 91.413 checks, as appropriate, after flying for at
least two years?
Would any EFIS owners and operators care to comment on these points?.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
---------------------------------------------------
From: "William Gill" <wgill10(at)comcast.net>
Subject: RE: Avionics-List: Encoding Altimeter
OR...you could buy a Dynon and save even more during the IFR
recertification check. In fact, the avionics shops actually prefer the
Dynon due to their accuracy and simplicity.
Bill
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Rear Mounted Batteries - more questions |
>
>Bob.
>
>Started out with your published z14 drawing and began to understand the
>flow with them
>
>Then found the string referencing the z14_rough that uses non-local
>ground. Reviewed options and decided I wanted to use a central primary
>ground on the firewall / engine block.
>
>That particular string also is where the discussion of keeping the XFEED
>CNTCTR and the Battery Cntctrs located close and connected using
>copper/brass strapping which drove me to drawing up the very rough sketch
>with only one + fat wire running from the back to the front.
>
>I think the biggest weakness of the one wire concept is that I would
>loose some of the benefit of the aux alternator as it would have to keep
>the aux battery cntctr closed. Think I read in either the
>connection or the list that it takes about 1amp to keep the
>contactor closed. Obviously, Id lose 1/8th of the output of the SD8 in
>that scenario. Assuming that its okay to physically mount the xfeed
>contactor at the front instead of with the battery contactors, the only
>real advantage is one less + fat wire. Would still have to run
>something from the Aux alt and aux bus to the rear but it could be a
>smaller wire.
>
>So all that said, maybe the simplest most efficient design would be moving
>the xfeed contactor to the front.
>
>Also pondering the physical location of the battery bus (ie, the always
>hot bus). From what I can read it appears the recommendation is always
>having this bus physically located within 6-8 inches of the
>battery. Obviously this requires running wiring from the front to the
>back for all devices that you want powered via the battery bus. An option
>that I never see mentioned and therefore assume is a bad idea is to run
>one heavier wire from the rear mounted battery and physically locate the
>battery bus in the front. Again, I assume this is a bad idea but would
>you comment on why Im assuming that you wouldnt want a non-fused
>wire ran that distance but thought Id ask anyway.
>
>These rear-mounted batteries are requiring some noodling as to where to
>physically mount things. Guess that's why they call it experimental :)
>
>Thanks again for all your input. It sure helps to bounce things off
>someone that has done this more than once before.
>
>Doug
I've been pondering this discussion for the last day or so and
I wasn't pleased with the lack of elegance. It seemed that your
design goals were not well served with the present suite of hardware
(too heavy).
An FMEA study of Z-13/8 yields and excellent reliability scenario
but it cannot address the fact that some modern EFIS products are
unable to deal with the real world of millisecond long, bus brownout
during starter-inrush loads. See:
http://www.aeroelectric.com/Pictures/Curves/99_Saturn_SL1.jpg
Indeed, all single-battery systems are not designed to provide
a constant source of power that stays inside the operating
envelope of these computer based products.
One obvious solution is a second battery. The question is
how big? It only needs to supply power to a limited suite of
ship's hardware for a few tens of milliseconds while the starter
motor spins up at the onset of each cranking cycle. In terms
of ENERGY, the requirements are trivial. So the real sizing
considerations are for internal impedance of the battery. Ideally,
we'd like to put an array of AA NiMh cells in to support the e-bus
during brownout . . . but these cells have finicky charging
requirements. It's not that they wouldn't do the job . . . but
system design issues are more complex and parts count goes
up.
So what's a reasonable middle ground? Take a peek at:
Take a peek at this drawing I did last night:
http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8A(BrownOutBattery).pdf
Here I've suggested that you dump the #2 fat battery and
the fat contactors associated with #2 master and crossfeed.
Install a much smaller (7.2 AH, 5.5# 0.04 ohm) "brownout
battery" and a pair of cube power relays wired such that
the e-bus is supported ONLY by the brownout battery during
engine cranking and only while the main bus is loaded so
heavily that it cannot keep the EFIS from resetting.
This same technique could be added to any single battery
system (or even Z-14 where you wanted to use both batteries
for cranking). This modification to Z-13 does not burden the
SD-8 with supporting fat contactors that are never expected
to carry cranking currents . . . hence may be ably replaced
with smaller, plastic relays.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
I've been pondering this discussion for the last day or so and
I wasn't pleased with the lack of elegance. It seemed that your
design goals were not well served with the present suite of hardware
(too heavy).
An FMEA study of Z-13/8 yields and excellent reliability scenario
but it cannot address the fact that some modern EFIS products are
unable to deal with the real world of millisecond long, bus brownout
during starter-inrush loads. See:
http://www.aeroelectric.com/Pictures/Curves/99_Saturn_SL1.jpg
Indeed, no single-battery systems is designed to provide
a constant source of power that stays inside the operating
envelope of these computer based products.
One obvious solution is a second battery. The question is
how big? It only needs to supply power to a limited suite of
ship's hardware for a few tens of milliseconds while the starter
motor spins up at the onset of each cranking cycle. In terms
of ENERGY, the requirements are trivial. So the real sizing
considerations are for internal impedance of the battery. Ideally,
we'd like to put an array of AA NiMh cells in to support the e-bus
during brownout . . . but these cells have finicky charging
requirements. It's not that they wouldn't do the job . . . but
system design issues are more complex and parts count goes
up.
So what's a reasonable middle ground? Take a peek at:
Take a peek at this drawing I did last night:
http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8A(BrownOutBattery).pdf
Here I've suggested that you dump the #2 fat battery and
the fat contactors associated with #2 master and crossfeed.
Install a much smaller (7.2 AH, 5.5# 0.04 ohm) "brownout
battery" and a pair of cube power relays wired such that
the e-bus is supported ONLY by the brownout battery during
engine cranking and only while the main bus is loaded so
heavily that it cannot keep the EFIS from resetting.
This same technique could be added to any single battery
system (or even Z-14 where you wanted to use both batteries
for cranking). This modification to Z-13 does not burden the
SD-8 with supporting fat contactors that are never expected
to carry cranking currents . . . hence may be ably replaced
with smaller, plastic relays.
P.S. Here's an exemplar battery that seems well suited to
this task:
http://aeroelectric.com/Mfgr_Data/Batteries/Panasonic/LC-R127R2P.pdf
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Dual alternator single shunt |
>Take a look at Z-12. As is the case in most all of Bob's schematics (I
>think) the shunt is in series with the alternator output, which connects
>to the upstream side of the starter contactor. The starter motor current
>goes through the starter contactor. That heavy current does not split off
>to the side, through the alternator. In that position the shunt senses the
>output of the alternator.
>
>Ron
>
>
>On Mon, Apr 21, 2008 at 7:58 PM, David & Elaine Lamphere
><lamphere(at)vabb.com> wrote:
>><lamphere(at)vabb.com>
>>
>>I just have to ask ....
>>
>>If you use a shunt that "sees" all current flowing from the battery and
>>the starter draws 200a, doesn't that hit the 50ma ammeter (if using a 40a
>>shunt) with 250ma?? Doesn't seem like that would do the ammeter any good...
>>
>>I must be missing something about this... sorry..
>>
>>Dave
Ron, that is correct. In the instrumentation chapter of the Connection
I suggested that one MIGHT install a battery ammeter in series
with the battery as long as the equipment (shunt size for wattage
dissipation) and the associated instrument was not adversely
affected by the starter inrush currents during cranking. This
was a bit of a brain fart that wound up in print and I should have
fixed it years ago. In the TC experimental instrumentation business,
we stick all kinds of shunts about anywhere there is a curiosity
about current flows . . . including in series with batteries. But
to consider this particular architecture as the normal operating
system for an airplane is exceedingly inelegant.
If one is interested in knowing currents during normal flight
then having a way to observe alternator loading is about as
useful as anything one might choose to do . . . hence later
recommendations in the Z-figures that alternator loadmeters
be a part of ship's instrumentation.
I'm working on an e-book version of the 'Connection along
with an overhaul of several chapters. R12 will include
a rewrite of the instrumentation chapter which will
(among other things) delete the suggestion of a battery
ammeter shunt. In fact, the whole idea of a battery ammeter
will be discussed for the purposes of illuminating history
but it will NOT be recommended for new design.
Bob . . .
________________________________________________________________________________
| From: | Bret Smith <smithhb(at)tds.net> |
| Subject: | Re: Brownout Battery System P.S. |
Bob, this is similar to our design I showed you when you were in Atlanta...
http://www.flightinnovations.com/images/wiring/Main%20Power%20Distribution%20010308.JPG
Bret Smith
RV-9A "Canopy"
Blue Ridge, GA
www.FlightInnovations.com
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
Sent: Tuesday, April 22, 2008 9:54 AM
Subject: AeroElectric-List: Re: Brownout Battery System P.S.
>
>
> I've been pondering this discussion for the last day or so and
> I wasn't pleased with the lack of elegance. It seemed that your
> design goals were not well served with the present suite of hardware
> (too heavy).
>
> An FMEA study of Z-13/8 yields and excellent reliability scenario
> but it cannot address the fact that some modern EFIS products are
> unable to deal with the real world of millisecond long, bus brownout
> during starter-inrush loads. See:
>
> http://www.aeroelectric.com/Pictures/Curves/99_Saturn_SL1.jpg
>
> Indeed, no single-battery systems is designed to provide
> a constant source of power that stays inside the operating
> envelope of these computer based products.
>
> One obvious solution is a second battery. The question is
> how big? It only needs to supply power to a limited suite of
> ship's hardware for a few tens of milliseconds while the starter
> motor spins up at the onset of each cranking cycle. In terms
> of ENERGY, the requirements are trivial. So the real sizing
> considerations are for internal impedance of the battery. Ideally,
> we'd like to put an array of AA NiMh cells in to support the e-bus
> during brownout . . . but these cells have finicky charging
> requirements. It's not that they wouldn't do the job . . . but
> system design issues are more complex and parts count goes
> up.
>
> So what's a reasonable middle ground? Take a peek at:
>
>
> Take a peek at this drawing I did last night:
>
> http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8A(BrownOutBattery).pdf
>
> Here I've suggested that you dump the #2 fat battery and
> the fat contactors associated with #2 master and crossfeed.
> Install a much smaller (7.2 AH, 5.5# 0.04 ohm) "brownout
> battery" and a pair of cube power relays wired such that
> the e-bus is supported ONLY by the brownout battery during
> engine cranking and only while the main bus is loaded so
> heavily that it cannot keep the EFIS from resetting.
>
> This same technique could be added to any single battery
> system (or even Z-14 where you wanted to use both batteries
> for cranking). This modification to Z-13 does not burden the
> SD-8 with supporting fat contactors that are never expected
> to carry cranking currents . . . hence may be ably replaced
> with smaller, plastic relays.
>
> P.S. Here's an exemplar battery that seems well suited to
> this task:
>
> http://aeroelectric.com/Mfgr_Data/Batteries/Panasonic/LC-R127R2P.pdf
>
>
> Bob . . .
>
>
>
________________________________________________________________________________
| From: | "David & Elaine Lamphere" <lamphere(at)vabb.com> |
| Subject: | Re: Dual alternator single shunt |
Ron, Bob,
Please understand that I was and still am in agreement with the location of
the shunt as shown in the schematic you mentioned. While my electrical
system will be simpler, that is the route I am taking.
It just sounded like the individual that started this thread was
contemplating a singular shunt for the whole system (where the starter
current would go through the shunt). Thanks for making clear the details.
Dave
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
Sent: Tuesday, April 22, 2008 10:26 AM
Subject: Re: AeroElectric-List: Dual alternator single shunt
>
>
>
>>Take a look at Z-12. As is the case in most all of Bob's schematics (I
>>think) the shunt is in series with the alternator output, which connects
>>to the upstream side of the starter contactor. The starter motor current
>>goes through the starter contactor. That heavy current does not split off
>>to the side, through the alternator. In that position the shunt senses the
>>output of the alternator.
>>
>>Ron
>>
>>
>>On Mon, Apr 21, 2008 at 7:58 PM, David & Elaine Lamphere
>><lamphere(at)vabb.com> wrote:
>>><lamphere(at)vabb.com>
>>>
>>>I just have to ask ....
>>>
>>>If you use a shunt that "sees" all current flowing from the battery and
>>>the starter draws 200a, doesn't that hit the 50ma ammeter (if using a 40a
>>>shunt) with 250ma?? Doesn't seem like that would do the ammeter any
>>>good...
>>>
>>>I must be missing something about this... sorry..
>>>
>>>Dave
>
> Ron, that is correct. In the instrumentation chapter of the Connection
> I suggested that one MIGHT install a battery ammeter in series
> with the battery as long as the equipment (shunt size for wattage
> dissipation) and the associated instrument was not adversely
> affected by the starter inrush currents during cranking. This
> was a bit of a brain fart that wound up in print and I should have
> fixed it years ago. In the TC experimental instrumentation business,
> we stick all kinds of shunts about anywhere there is a curiosity
> about current flows . . . including in series with batteries. But
> to consider this particular architecture as the normal operating
> system for an airplane is exceedingly inelegant.
>
> If one is interested in knowing currents during normal flight
> then having a way to observe alternator loading is about as
> useful as anything one might choose to do . . . hence later
> recommendations in the Z-figures that alternator loadmeters
> be a part of ship's instrumentation.
>
> I'm working on an e-book version of the 'Connection along
> with an overhaul of several chapters. R12 will include
> a rewrite of the instrumentation chapter which will
> (among other things) delete the suggestion of a battery
> ammeter shunt. In fact, the whole idea of a battery ammeter
> will be discussed for the purposes of illuminating history
> but it will NOT be recommended for new design.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: Encoding Altimeter |
bakerocb(at)cox.net wrote:
>
> A) Maybe EFIS removal and reinstallation is no big deal, but I
> envision a bunch of connections, particularly if it is the type of
> EFIS that also includes displaying engine performance parameters.
I don't know about others, but the Dynon unit is one DB-25 connector and
the pitot, static, and AoA connections.
http://www.dynonavionics.com/downloads/EFIS%20D100.pdf
It slides into a rack with one screw to lock it into place.
________________________________________________________________________________
| From: | D Fritz <dfritzj(at)yahoo.com> |
| Subject: | Re: LED Landing Lights |
Thanks Bob, can't wait to see the news!
Dan
---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
>
>Bob, this is similar to our design I showed you when you were in Atlanta...
>http://www.flightinnovations.com/images/wiring/Main%20Power%20Distribution%20010308.JPG
Yeah . . . but the only time the brownout battery gets
properly attached to the system for charge maintenance is
when the e-bus alternate feed switch is closed.
The architecture I posted keeps the brownout battery
connected across the main battery at all times except while
cranking the engine. Zero demands on pilot for proper
orientation of switches.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Dual alternator single shunt |
>
>
>Ron, Bob,
>
>Please understand that I was and still am in agreement with the location
>of the shunt as shown in the schematic you mentioned. While my electrical
>system will be simpler, that is the route I am taking.
>
>It just sounded like the individual that started this thread was
>contemplating a singular shunt for the whole system (where the starter
>current would go through the shunt). Thanks for making clear the details.
>
>Dave
My reply was intended to address all the conversation about shunts
wherein one thread was talking about load-meters and the other was
getting battery-ammeters stirred into the same conversation. Don't
recall exactly what was said by whom but there was no intention
of "standing anyone against the wall."
Bob . . .
________________________________________________________________________________
| Subject: | Re: Brownout Battery System P.S. |
| From: | "grjtucson" <george(at)georgejenson.com> |
nuckolls.bob(at)cox.net wrote:
>
> Yeah . . . but the only time the brownout battery gets
> properly attached to the system for charge maintenance is
> when the e-bus alternate feed switch is closed.
>
> The architecture I posted keeps the brownout battery
> connected across the main battery at all times except while
> cranking the engine. Zero demands on pilot for proper
> orientation of switches.
>
> Bob . . .
Bob,
I like the new drawing but help me out in understanding how the E-Bus alternate
feed relay gets energized and thus energizes the e-bus in the event the master
April 11, 2008 - April 22, 2008
AeroElectric-Archive.digest.vol-ht