Today's Message Index:
----------------------
1. 01:27 AM - Re: B&C LR-3C question (Werner Schneider)
2. 04:57 AM - Facet fuel pumps - foam solvent? (Finn Lassen)
3. 05:09 AM - Re: Re: Power Diode Drops (Trampas)
4. 05:16 AM - Re: B&C LR-3C question (F1Rocket@comcast.net)
5. 05:20 AM - Re: Re: Power Diode Drops (Brian Lloyd)
6. 05:22 AM - battery capacity remaining (Brian Lloyd)
7. 05:41 AM - Main Bus Feed (Jim Stone)
8. 06:51 AM - 14V to 28V inverter? (Crapse, Richard W (Rick), WCS)
9. 08:17 AM - Re: B&C LR-3C question (James Redmon)
10. 08:17 AM - Re: Re: Power Diode Drops (Paul Messinger)
11. 08:39 AM - Re: Re: Power Diode Drops (Brian Lloyd)
12. 09:42 AM - Re: Rocker Switch Problems-Followup (Scott Diffenbaugh)
13. 10:00 AM - Re: 14V to 28V inverter? (Brian Lloyd)
14. 10:05 AM - Re: 14V to 28V inverter? (Jerzy Krasinski)
15. 10:13 AM - Re: Re: Power Diode Drops (Brian Lloyd)
16. 10:28 AM - Re: 14V to 28V inverter? (Jerzy Krasinski)
17. 10:33 AM - Re: Re: Power Diode Drops (Werner Schneider)
18. 10:33 AM - Re: Re: Power Diode Drops (Werner Schneider)
19. 10:33 AM - Re: Re: Power Diode Drops (Robert L. Nuckolls, III)
20. 10:40 AM - Re: Rocker Switch Problems-Followup (Robert L. Nuckolls, III)
21. 11:25 AM - Re: Power Diode Drops (jmfpublic@comcast.net)
22. 11:40 AM - Re: Re: Power Diode Drops (echristley@nc.rr.com)
23. 01:42 PM - Mr. Brain OT (Eric M. Jones)
24. 02:24 PM - Re: Mr. Brain OT (Harley)
25. 02:28 PM - Re: Mr. Brain OT (David Glauser)
26. 02:32 PM - Re: Re: Power Diode Drops (Paul Messinger)
27. 02:45 PM - Re: Mr. Brain OT (Chad Robinson)
28. 02:46 PM - Re: Digital Music in the Cockpit (frequent flyer)
29. 03:01 PM - Re: Re: Power Diode Drops (Paul Messinger)
30. 03:01 PM - Re: Re: Power Diode Drops (Paul Messinger)
31. 03:11 PM - Re: Re: Power Diode Drops (Phil Birkelbach)
32. 03:21 PM - Re: Digital Music in the Cockpit (Chad Robinson)
33. 05:22 PM - Re: Re: Power Diode Drops (Kevin Horton)
34. 06:12 PM - Re: Re: Power Diode Drops (jmfpublic@comcast.net)
35. 07:38 PM - Re: AeroElectric-List Digest: 32 Msgs - 06/03/04 (Dave Ford)
36. 08:13 PM - Re: Digital Music in the Cockpit (frequent flyer)
37. 08:13 PM - Re: Digital Music in the Cockpit (frequent flyer)
38. 08:31 PM - Re: Digital Music in the Cockpit (richard@riley.net)
39. 08:44 PM - Re: B&C LR-3C question (Emrath)
40. 09:06 PM - Re: Re: AeroElectric-List Digest: 32 Msgs - 06/03/04 (Chad Robinson)
41. 09:26 PM - Re: B&C LR-3C question (James Redmon)
Message 1
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| Subject: | Re: B&C LR-3C question |
--> AeroElectric-List message posted by: "Werner Schneider" <wernerschneider@compuserve.com>
Hello James,
Bob did post a picture for that and I'm running this way without any
problems, a 220 ohm over the diode and a 220 in series direction regulator.
I will send you in a direct mail the sketch (jpg).
Werner
----- Original Message -----
From: "James Redmon" <james@berkut13.com>
Subject: AeroElectric-List: B&C LR-3C question
> --> AeroElectric-List message posted by: "James Redmon"
<james@berkut13.com>
>
> All,
>
> I was working with B&C on this, but the gentleman is out of pocket for a
> couple weeks and thought one of you might know the answer.
>
> I am using a LED instead of an incandescent lamp for the OV light. The
> issue I discussed with B&C was that the LED never goes out...it stays on
> (dimly) even when the regulator is turned off. When I turn on the
regulator
> (battery only) the LED does blink properly. He mentioned that the
regulator
> bleeds a little current on the lamp pin all the time - not enough to
> illuminate a lamp, but a LED still glows slightly.
>
> He mentioned a fix of placing a 520-ohm resistor between Pin 5 (the lamp
> lead) and another pin on the regulator. I have misplaced my notes and can
> not remember specifically which other pin to connect the resistor to.
>
> Does someone happen to know which one I should use? If not, I can always
> wait a
> couple of weeks until Tim gets back.
>
> Thanks!
>
> James Redmon
> Berkut #013 N97TX
> http://www.berkut13.com
>
>
Message 2
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| Subject: | Facet fuel pumps - foam solvent? |
0.1 HTML_TITLE_EMPTY BODY: HTML title contains no text
--> AeroElectric-List message posted by: Finn Lassen <finn.lassen@verizon.net>
I took one of my Facet fuel pumps apart this evening. One of the square
solid state types.
Sunday nigth when I wanted to go fly one of the pumps didn't when I
turned on the power. After fiddeling a bit with it it started up. I had
also noticed occasional fuel pressure drops (very brief) over the last
few months.
This lead me to believe that the pump was intermittently bad.
I'm very impressed with the construction of these pumps. All of the
electronics are embedded completely in foam.
It's hard to see how one of these pumps could fail electrically. I
suppose that heat cycling could lead to a bad connection on the circuit
board even though all components are held firmly in place by the foam.
Of course it's impossible to inspect the electronics because of the foam.
Anybody here know of a solvent that will dissolve the foam and not harm
the electronic components and circuit board?
Finn
Message 3
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Trampas" <tstern@nc.rr.com>
Personally I stand with Brian on this one, that is wasted power is wasted
power, it in my opinion is like throwing extra weight in the plane.
I personally like to design things for at least 2x margin. That is if a
circuit breaker is rated at 5Amps then the wiring should be able to handle
at least 10Amps continuously. So lets say that you have a silicon (spelled
it right this time) diode and running 5Amps. From Paul's numbers:
Amps Silicon Schottky
5A 4.3W 1.6W
10A 8.9W 3.4W
Now I do not know about other devices by my engine monitor
(www.sterntech.com) takes about 10W of power. Thus at 10A your wasting
almost as much power as the engine monitor takes. To put it another way if
you have a 10A alternator, at 10A E-bus draw you would be wasting 6% of the
alternator's power. At 5A and silicon you would be wasting about 3% of the
alternator's power.
Another reason it is good to use Schottky diodes is that you will most
likely have your engine monitor hanging off the E-bus. As such your battery
voltage measurement will but low by about 0.9V for a silicon diode. Of
course my engine monitor lets you calibrate the voltage measurement to
compensate but others will not.
Brian, sorry about misspelling your name, fingers are faster than brain more
often than I like to admit.
Regards,
Trampas Stern
Stern Technologies
4321 Waterwheel Dr
Raleigh NC 27606
919-832-8441 Ext. 12 (voice)
919-832-8441 (fax)
www.sterntech.com
tstern@sterntech.com
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Subject: Re: AeroElectric-List: Re: Power Diode Drops
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
At 09:37 PM 6/3/2004 -0400, you wrote:
>--> AeroElectric-List message posted by: "Eric M. Jones"
<emjones@charter.net>
>
>My numbers are similar to Paul's, for the 276-1185 diode bridge I got from
>Radio Shack versus the IR 100BGQ-030 Schottky, the numbers are:
>
>Load Radio Shack Schottky
>5A 0.86 Vf 0.32 Vf
>10A 0.89 0.34
>11A 0.91 0.35
>16A 0.94 0.35
>
>At any point the Schottky ran far cooler than the RS diode.
>
>The energy left in the battery is extremely important. . .
This is a moot point. The battery is never used to supply normal
path current. The only time the diode is in service is while the
alternator
is running and main bus voltage is 13.8 to 14.6 volts. People keep
tossing around these gawd-awful power dissipations as significant
to battery-only endurance when the diode carries no current during
alternator-out operations. Further, anyone running an e-bus load of
more than 5 amps continuous through ANY diode may be running the wrong
architecture.
> One of the techniques
>that is now being used in battery operated devices is to use circuitry that
>jacks up the output voltage to whatever you want while it sucks the
>batteries flat. Example---a single 1.5 Volt cell drives circuitry that
>produces 9V in a transistor- battery-sized package with flat discharge
until
>dead. MUCH greater capacity, MUCH lower cost. Cool....
. . . completely inapplicable in this instance. Battery only ops tie
all e-bus equipment directly to the battery. E-bus loads should provide
useful operation down to 10.5 volts (battery capacity less than 5%).
Jacking
up the parts count to squeeze that last 5% out of the battery is an
confession to having undersized the battery and/or subjecting it
to poor preventative maintenance.
>So the Schottky can use much more of the energy contained in the battery.
>That energy is sitting there at a great penalty in weight if you don't use
>it. Someone should figure this out--it's probably a pound or more.
>
>This is not a case of what Brian calls "angels dancing on the head of a
>pin". This is not a subtle difference at all.
Diode drop and wattage could be important if folks choose
to use it in a manner for which it was never suggested or intended.
Bob . . .
Message 4
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| Subject: | Re: B&C LR-3C question |
--> AeroElectric-List message posted by: F1Rocket@comcast.net
Ditto that. Here's the wiring diagram.
http://f1rocket.home.comcast.net/Alternator.pdf
Randy
F1 Rocket.
> --> AeroElectric-List message posted by: "Werner Schneider"
> <wernerschneider@compuserve.com>
>
> Hello James,
>
> Bob did post a picture for that and I'm running this way without any
> problems, a 220 ohm over the diode and a 220 in series direction regulator.
>
> I will send you in a direct mail the sketch (jpg).
>
> Werner
>
> ----- Original Message -----
> From: "James Redmon" <james@berkut13.com>
> To: <aeroelectric-list@matronics.com>
> Subject: AeroElectric-List: B&C LR-3C question
>
>
> > --> AeroElectric-List message posted by: "James Redmon"
> <james@berkut13.com>
> >
> > All,
> >
> > I was working with B&C on this, but the gentleman is out of pocket for a
> > couple weeks and thought one of you might know the answer.
> >
> > I am using a LED instead of an incandescent lamp for the OV light. The
> > issue I discussed with B&C was that the LED never goes out...it stays on
> > (dimly) even when the regulator is turned off. When I turn on the
> regulator
> > (battery only) the LED does blink properly. He mentioned that the
> regulator
> > bleeds a little current on the lamp pin all the time - not enough to
> > illuminate a lamp, but a LED still glows slightly.
> >
> > He mentioned a fix of placing a 520-ohm resistor between Pin 5 (the lamp
> > lead) and another pin on the regulator. I have misplaced my notes and can
> > not remember specifically which other pin to connect the resistor to.
> >
> > Does someone happen to know which one I should use? If not, I can always
> > wait a
> > couple of weeks until Tim gets back.
> >
> > Thanks!
> >
> > James Redmon
> > Berkut #013 N97TX
> > http://www.berkut13.com
> >
> >
>
>
>
>
>
>
Message 5
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
Robert L. Nuckolls, III wrote:
> This is a moot point. The battery is never used to supply normal
> path current. The only time the diode is in service is while the alternator
> is running and main bus voltage is 13.8 to 14.6 volts. People keep
> tossing around these gawd-awful power dissipations as significant
> to battery-only endurance when the diode carries no current during
> alternator-out operations. Further, anyone running an e-bus load of
> more than 5 amps continuous through ANY diode may be running the wrong
> architecture.
You are right and I pointed that out last night. But I have two additional points
to make.
Some people are building airplanes that are engineering "works of art." Their
goal is to craft something that is as close to their image of perfection as they
can achieve. They do not use cast aluminum parts where machined billet aluminum
parts are available. The Schottky diode is a better diode for the purposes
described herein. Yes a standard silicon rectifier is "good enough" but people
want to go beyond "good enough". You only have to look at their wiring
or firewall forward to see what I mean. OTOH, If the MTBF were higher for the
silicon diode I would agree with you instantly. First and foremost it is about
safety and reliability.
And as for "5A is good enough", it may not be. I may find that to complete a flight
comfortably I will want to turn on more bits of avionics to safely and legally
complete an approach. For that reason I want all my avionics on the e-buss.
Each one has an on/off switch so I can turn off what I am not using to
conserve energy in the battery but in the last 10 minutes or so I may want everything.
Arbitrarily limiting the e-buss to 5A seems a bit limiting to me.
And, no, that does not include the landing lights. :-)
--
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
Message 6
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| Subject: | battery capacity remaining |
--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
One thing I have not seen discussed here are battery energy remaining meters.
These are devices that tell you how much energy is remaining in the battery and
how long the battery will battery will provide power at the current drain.
These are common devices in boats, RVs, and people living on alternative energy
systems (solar and wind power). Why not in aircraft?
--
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
Message 7
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--> AeroElectric-List message posted by: "Jim Stone" <jrstone@insightbb.com>
Hi Guys,
I'm building a Harmon Rocket II and have two 17ah batts in the baggage compartment
each with their own battery contactor. From the contactor, I ran #2 wire
fwd thru the firewall, some ten feet or so, to the starter contactor.
My Main and Endurance busses will be located on the cockpit side of the FW which
is a very short distance from the starter contactor and main battery wire.
Question 1: Would it be better to home run another large wire (#4 or 6 awg) from
the battery contactor as shown in dwg 11 to the main bus, or pick up the shortest
route, directly from the starter contactor (hot side of course), using
a much smaller wire (8 awg or so). The main potential problem with connecting
to the starter contactor is it is on the engine side of the FW and in the event
of a fire, I would loose my feed to the Main bus as the wire burns. By the
way, the main batt wires both + and - run thru a stainless steel handrail 90
deg fitting on the FW so there is no bolt thru the FW for the + battery lead.
Question 2: If I go with the home run method, do you recommend using a different
route for the wire within the aircraft or run it along side the #2 +and- wires?
Thanks,
Message 8
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| Subject: | 14V to 28V inverter? |
--> AeroElectric-List message posted by: "Crapse, Richard W (Rick), WCS" <rwcrapse@att.com>
I would like to know more about that. That would give me a box to power other avionics
off my bus. Details, please.
Rick
Cozy 3 #40 - Building the strakes.
Message 9
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| Subject: | Re: B&C LR-3C question |
--> AeroElectric-List message posted by: "James Redmon" <james@berkut13.com>
Thanks all!! This is different information than I received from Tim at
B&C...but makes much more sense to me. This should work fine.
What a great group!
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
Do not archive
----- Original Message -----
From: <F1Rocket@comcast.net>
Subject: Re: AeroElectric-List: B&C LR-3C question
> --> AeroElectric-List message posted by: F1Rocket@comcast.net
>
> Ditto that. Here's the wiring diagram.
>
> http://f1rocket.home.comcast.net/Alternator.pdf
>
> Randy
> F1 Rocket.
>
>
> > --> AeroElectric-List message posted by: "Werner Schneider"
> > <wernerschneider@compuserve.com>
> >
> > Hello James,
> >
> > Bob did post a picture for that and I'm running this way without any
> > problems, a 220 ohm over the diode and a 220 in series direction
regulator.
> >
> > I will send you in a direct mail the sketch (jpg).
> >
> > Werner
Message 10
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
Bob and Brian
Points to consider
Approximately 1/2V is not trivial depending on your wiring design. An e-bus
load thru a diode is a very common design. At a battery load of 2-10 amps
you get more power out of your Xponder and or Com with 12v vs 11.5v and your
battery will be usable longer. Eventually the battery dies but its end of
life voltage is always effectively 1/2V lower with the subject diode which
can be significant time in flight duration depending on the load.
Consider the data for an Odyssey battery. 1/2V is 40% of the total energy.
From the Odyssey specifications the following.
12.3V = 60% state of charge
11.8V = 20% state of charge.
Note the above voltages are for a battery that is unloaded and thus not
directly applicable. Loaded voltages will be lower and load dependent. I
reference this info to illustrate the point that 1/2V is not a small
difference in usable energy at end of life voltage as noted later.
As the data is nearly linear you get a 40% loss in usable capacity
regardless of where you define end of life voltage. There is only 10% left
at 11.7V plus what ever diode drop is in play. I do not know about the rest
of you, but I like the extra voltage to my com and xponder where the added
voltage can (and typically does)increase power output and perhaps make the
difference in being heard and "seen on the radar".
With battery end of charge around 11.6V a "normal diode has dropped the
e-bus voltage to below 11.0V. Even equipment that "meets" DO-160 may not be
required to below that V as DO-160 has no requirement for equipment to even
work below 11.0V unless it was specifically designed to do so and that is
optional.
So lets assume your com requires 11.0V minimum and that it does meet DO-160.
If you use a Radio shack diode vs a Schottky you can shorten your time to
the end of life (11.0V e-bus ) with a 4.0 amp average load by 1/4 or more.
Thats a lot!
Sure none of us ever expect to be in a case where we need every drop of
energy from a battery to make it safely to the airport, but why not design a
system that is simple (no extra switches to bypass diodes) KISS and use the
best part for the job not just what can be made to work under normal usage.
Also reducing the heat load (typically behind the panel) is not
insignificant to me.
It never ceases to amaze me that people will spend $50,000 on a avionics
package and then quibble over the difference in the lowest cost battery or a
more expensive diode that improves emergency operations.
Paul
Message 11
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
Trampas wrote:
> --> AeroElectric-List message posted by: "Trampas" <tstern@nc.rr.com>
>
> Personally I stand with Brian on this one, that is wasted power is wasted
> power, it in my opinion is like throwing extra weight in the plane.
It is purist thing.
> Brian, sorry about misspelling your name, fingers are faster than brain more
> often than I like to admit.
No worries. I get a chuckle out of it. Heck, my nickname in elementary school
was "Mr. Brain". I was the nerdy guy who brought books on rocket engine design
or the Radio Amateur's Handbook to school instead of the Hardy Boys.
--
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
Message 12
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| Subject: | Re: Rocker Switch Problems-Followup |
--> AeroElectric-List message posted by: "Scott Diffenbaugh" <diff@foothill.net>
Bob, Thanks for the feedback. You asked which datasheet I was looking at.
The copy that was faxed to me that shows a schematic of the 6 power
terminals is:
http://catalog.sensing.honeywell.com/printfriendly.asp?FAM=tr&PN=AML34FBA4AC
01 --- it no longer is a valid URL as they apparently deleted it while they
are correcting it. Honeywell's technical rep Wendy Domino's e-mail which
was posted on Aircraft Engraver's web site showed the datasheet info you
cite but for the "AC" code stated "2-pole six terminals". I had not seen
the datasheet you cite below, which apparently is the correct one, but I
suppose one needs to know that one form A switch only has 2 terminals.
I checked out the "TP" switches. They would require a major rework of
my
panel. Looks like I will have the operators re-engraved on the upper half
and live with it. Thanks again. Scott
Time: 12:23:01 PM PST US
From: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
Subject: Re: AeroElectric-List: Rocker Switch Problems
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
At 07:26 AM 6/1/2004 -0700, you wrote:
>--> AeroElectric-List message posted by: "Scott Diffenbaugh"
><diff@foothill.net>
>
>Just received my engraved rocker switch operators (plastic covers) for my
>illuminated Honeywell (Micro Switch) Double Pole AML34FBA4AC01 (15A
>resistive @ 12v DC) panel switches. Since the switches are low on the
panel,
>I had the engraving done on the lower half per Aircraft Engravers
>recommendation. Turns out the internal light bulb only illuminates one
half
>of the operator, which happens to be the top half with the switch mounted
>conventionally (push top for on and bottom for off). Any suggestions?
>
> There is a lot more to the story, so if you are interested, read
on.
>Aircraft Engravers sells and engraves the operators (plastic covers), but
>does not sell the switches, thus refers you to a distributor. Prior to
>ordering same, I obtained Honeywell's data sheet showing six terminals with
>ON-ON positions, i.e. the switch could be rotated 180 degrees, placing the
>light bulb on either the upper or lower face.
Which data sheet are you looking at? The Honeywell website data
sheet I found is
http://content.honeywell.com/sensing/prodinfo/manual/catalog/c30035.pdf
If you dissect the part number cited above we deduce as follows:
AML34F = rectangular 1-lamp circuit
B = black
A = no lamp installed
4 = .187" solder/fast-on terminal
AC = two form A switches
01 = operating action is ON-OFF (maintained in both states)
If the switch has six terminals, then perhaps two of them are not
used since the "A" value for lamp suggests there is no lamp installed
in the parts you have. You need a "C" part for 12v lamp, or "E" for
a 28v lamp.
> I also received a copy of
>Honeywell's technical representative's e-mail confirming the switch has 6
>terminals. They have now confirmed that both pieces of information are
>incorrect and in fact the switch has 4 switch terminals (2 pole single
>throw) plus an independent light circuit.
That jives with the data sheet I've cited above.
> When I brought this to Aircraft
>Engravers attention, they were dumfounded, having engraved hundreds of
>operators on the lower half with no mention of my problem. They suggested
I
>post this message. Am I overlooking the obvious?
The data sheet does indicate that only the upper half of the switch
is illuminated.
> Options considered so far:
> Engrave upper half - difficult to read upper half when
> switch is in OFF
>position due to location on bottom of panel.
>
> Install switch upside down - this would work but I am
> afraid of a
>potential "John Denver" result and I don't think the FAA inspector would
>like it.
More importantly, would YOU like it? How hard is it to get one
of these switches apart? You might be able to modify them to
put the lamp on the other side . . . better yet, while you're
hammer-n-saw'n on them, change over to white or other color
leds for illumination.
> Find another DPDT ON-ON switch with 6 terminals- Panel is
> cut, final
>wiring near complete (except for switches), can't find a switch the same
>size.
>
> Modify the switch to let bulb light reach the bottom half
> - cut and
>drilled the switch mechanism to no avail. Light won't transfer.
Hmmm . . . that answers that question . . .
> Use Honeywell's 3 amp switch with 6 terminals and add
> solid state relays-I
>would need 7 relays (out of 12) and would like to avoid the complexity.
>
> Turn on cockpit light - Everything on panel is internally
> lit. No plans
>for a cockpit light other than battery backup flashlight.
You could go with non-illuminated switches and illuminate a reverse
engraved overlay panel. Leds could be used to light this up as well.
I saw some Glasair panels years ago that used the TP series rockers
from Honeywell. These feature separate operators that you can buy
in a translucent white, engrave front faces, and back-light with
LEDs or other small lamps. Best yet, the TP series rocker switches
are available in all the special functions including progressive
transfer. See:
http://catalog.sensing.honeywell.com/pdbdownload/images/12pa5.series.chart.1
.pdf
http://catalog.sensing.honeywell.com/printfriendly.asp?FAM=tr&PN=102TP81-10
>I would appreciate anyone's thoughts on this matter.
This is an excellent illustration that supports Nuckolls' love affair
with toggle switches. There are REALLY great looking products
out there that will certainly dress up your panel . . . but
at the end of the day, the TASK of opening one set of contacts in
favor of closing another set of contacts to make something electrical
happen is the same whether it's a $5 toggle switch or a $50, back-lighted
rocker.
Bob . . .
Scott Diffenbaugh
diff@foothill.net
Message 13
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| Subject: | Re: 14V to 28V inverter? |
--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
Crapse, Richard W (Rick), WCS wrote:
> I would like to know more about that. That would give me a box to power other
avionics off my bus. Details, please.
I used a little boost-type inverter chip from Maxim, the MAX669. Here is the application note: http://www.maxim-ic.com/appnotes.cfm/appnote_number/910
This is great for turning a 28V gyro into a 14V gyro. I found that I could buy
overhauled 28V gyros much cheaper than I could buy 14V gyros so this is what
I did to power them from the 14V system..
This is not a universal 28V power supply since it can only source about 1A.
There are high-power step-up converters available if you care to look. The company that makes the battery equalizer I use on my boat (I need both 12V and 24V from my boat battery bank) also makes high-power step-up and step down converters. See http://www.surepower.com/Products/dc2dc.asp and http://www.surepower.com/pdf/ebr_dcdc.pdf
--
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
Message 14
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| Subject: | Re: 14V to 28V inverter? |
--> AeroElectric-List message posted by: "Jerzy Krasinski" <krasinski@provalue.net>
----- Original Message -----
From: "Crapse, Richard W (Rick), WCS" <rwcrapse@att.com>
Subject: AeroElectric-List: 14V to 28V inverter?
> --> AeroElectric-List message posted by: "Crapse, Richard W (Rick), WCS"
<rwcrapse@att.com>
>
> I would like to know more about that. That would give me a box to power
other avionics off my bus. Details, please.
>
> Rick
> Cozy 3 #40 - Building the strakes.
>
>
Message 15
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
Paul Messinger wrote:
> Approximately 1/2V is not trivial depending on your wiring design. An e-bus
> load thru a diode is a very common design. At a battery load of 2-10 amps
> you get more power out of your Xponder and or Com with 12v vs 11.5v and your
> battery will be usable longer. Eventually the battery dies but its end of
> life voltage is always effectively 1/2V lower with the subject diode which
> can be significant time in flight duration depending on the load.
The point that your xpdr and comm will transmit with higher power is a good one.
Since you will directly connect your e-buss to the battery in the case of alternator
failure, the end-point voltage relative to diode drop is a non-issue.
--
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
Message 16
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| Subject: | Re: 14V to 28V inverter? |
--> AeroElectric-List message posted by: "Jerzy Krasinski" <krasinski@provalue.net>
----- Original Message -----
From: "Crapse, Richard W (Rick), WCS" <rwcrapse@att.com>
Subject: AeroElectric-List: 14V to 28V inverter?
> --> AeroElectric-List message posted by: "Crapse, Richard W (Rick), WCS"
<rwcrapse@att.com>
>
> I would like to know more about that. That would give me a box to power
other avionics off my bus. Details, please.
>
> Rick
> Cozy 3 #40 - Building the strakes.
Richard,
They are quite expensive. But one can use a converter from trucks and these
are far cheaper. Some trucks have -12V system. All radios etc.require +12V,
so they make -12V to +12V converters providing lots of current. These
converters can be used as +12V to +24V converters. Just connect -12V
terminal of the converter to the ground, connect ground of the converter to
+12V of the system, and you will have +24V at the +12V terminal of the
converter. This way you put the 12V output of the converter in series with
your battery and get 24 volts on the output. Remember that the box of the
converter is now at 12V potential, which is not a big deal in a plastic
plane. In a metal plane that would be scary, and I would recommend to
reconnect the box inside the converter to the -12V terminal which is now the
ground, of course disconnecting the old connection to the former ground of
the converter. I use Astron model 1515-18, which is 18 amps max output
converter. I have a plastic plane but I reconnected the box to -12V
terminal i.e. to the real ground of the plane. That was quite easy, I had to
put isolating washers under four screws. I got the converter on ebay for
$30. A new one is a few times more expensive, I forgot the price. Worth to
say that it is not a bad converter, it holds the output voltage, and it does
not take much current on the input if the output is not loaded, unlike many
others that swallow lots of current loaded or not.
Jerzy
forum is sponsored entirely through the Contributions
>
>
Message 17
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Werner Schneider" <wernerschneider@compuserve.com>
----- Original Message -----
From: "Paul Messinger" <paulm@olypen.com>
Subject: Re: AeroElectric-List: Re: Power Diode Drops
> --> AeroElectric-List message posted by: "Paul Messinger"
<paulm@olypen.com>
>
> Bob and Brian
>
> Points to consider
>
> Approximately 1/2V is not trivial depending on your wiring design. An
e-bus
> load thru a diode is a very common design. At a battery load of 2-10 amps
> you get more power out of your Xponder and or Com with 12v vs 11.5v and
your
> battery will be usable longer. Eventually the battery dies but its end of
> life voltage is always effectively 1/2V lower with the subject diode which
> can be significant time in flight duration depending on the load.
>
> Consider the data for an Odyssey battery. 1/2V is 40% of the total energy.
> From the Odyssey specifications the following.
>
> 12.3V = 60% state of charge
> 11.8V = 20% state of charge.
>
> Note the above voltages are for a battery that is unloaded and thus not
> directly applicable. Loaded voltages will be lower and load dependent. I
> reference this info to illustrate the point that 1/2V is not a small
> difference in usable energy at end of life voltage as noted later.
>
> As the data is nearly linear you get a 40% loss in usable capacity
> regardless of where you define end of life voltage. There is only 10% left
> at 11.7V plus what ever diode drop is in play. I do not know about the
rest
> of you, but I like the extra voltage to my com and xponder where the added
> voltage can (and typically does)increase power output and perhaps make the
> difference in being heard and "seen on the radar".
>
> With battery end of charge around 11.6V a "normal diode has dropped the
> e-bus voltage to below 11.0V. Even equipment that "meets" DO-160 may not
be
> required to below that V as DO-160 has no requirement for equipment to
even
> work below 11.0V unless it was specifically designed to do so and that is
> optional.
>
> So lets assume your com requires 11.0V minimum and that it does meet
DO-160.
> If you use a Radio shack diode vs a Schottky you can shorten your time to
> the end of life (11.0V e-bus ) with a 4.0 amp average load by 1/4 or more.
> Thats a lot!
>
> Sure none of us ever expect to be in a case where we need every drop of
> energy from a battery to make it safely to the airport, but why not design
a
> system that is simple (no extra switches to bypass diodes) KISS and use
the
> best part for the job not just what can be made to work under normal
usage.
>
> Also reducing the heat load (typically behind the panel) is not
> insignificant to me.
>
> It never ceases to amaze me that people will spend $50,000 on a avionics
> package and then quibble over the difference in the lowest cost battery or
a
> more expensive diode that improves emergency operations.
>
> Paul
>
>
Message 18
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Werner Schneider" <wernerschneider@compuserve.com>
Hello all,
I can agree on the fact, that the Schotky is the better diode, but:
-the argument of lower voltage and saving enegy and
having more power available on the e-bus is only partly true, because:
1. when the alternator is running (feed through main bus, voltage
drop occurs) we have a main bus voltage of 13.4V and the
voltage on the e.bus is high enough with both diodes.
2. when the alternator fails the e-bus is feeded through the e-bus
switch
directly and we do not go through the diode hence no voltage
drop,
no more energy available as diode not used.
What I can agree:
1. due to the higher voltage drop more heat is disipated which could
cause
some problems in narrow spaced paneld.
2. due to the higher voltage drop in an alternator on situation we
do need
to produce more energy (from the alternator) voltage drop diff 0.5V
with 5A load this accounts for 0.18A my ship has a standard
load of
around 15 A during cruise so this is around 1.2% lost energy
(with 10A
on the e-bus it would be 2.4%).
However, each should be happy with the system he wants to achieve, both
types are for sure a good choice, so it's up to you to decide.
My 2 cents
Werner (Glastar VFR)
Message 19
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 08:11 AM 6/4/2004 -0700, you wrote:
>--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
>
>Bob and Brian
>
>Points to consider
>
>Approximately 1/2V is not trivial depending on your wiring design. An e-bus
>load thru a diode is a very common design. At a battery load of 2-10 amps
>you get more power out of your Xponder and or Com with 12v vs 11.5v and your
>battery will be usable longer. Eventually the battery dies but its end of
>life voltage is always effectively 1/2V lower with the subject diode which
>can be significant time in flight duration depending on the load.
<snip>
. . . you're still missing the point. The manner in which an
e-bus normal feed diode is used never causes BATTERY energy to flow
through the diode to the E-bus.
The ONLY time the e-bus normal feed diode is expected to route power
to the e-bus is while the ALTERNATOR is functioning and the main bus
is operating at 13.8 or greater. Under these conditions, performance
differences for e-bus powered devices for 13.3 volts versus 12.8 volts
is indeed trivial. Further, when you have a 40A alternator providing
power (560 watts), then the difference between tossing off 5 watts
(Schottky diode) versus 10 watts (PN junction diode) is also trivial
and this assumes a 10A continuous duty load on the e-bus. If the e-bus
loads are on the order of 5A, then we're talking about a 2.5 watt
differential.
>It never ceases to amaze me that people will spend $50,000 on a avionics
>package and then quibble over the difference in the lowest cost battery or a
>more expensive diode that improves emergency operations.
You can use any diode you wish for EMERGENCY operations, I prefer to
use NO diodes during BATTERY-ONLY operations. The whole idea of
the e-bus is to keep an EMERGENCY situation from existing. This was
the thrust of Chapter 17. The AOPA dark-n-stormy-night story featured
in the 'Connection could have and should have been a non-story except
for the short-sightedness of both the OEM and regulatory community
in controlling the design of light aircraft electrical systems.
The diode bridge rectifier was chosen because of its ease of mounting
(has mounting hole, needs no electrical insulation from airframe) and
ease of connection (fast-on terminals). The selection wasn't based on
electrical performance . . . electrical performance was not
significant. This product was selected because it was inexpensive,
readily available from dozens of off-the-shelf sources, and easy to
mount. This device has a very high order probability of
successful implementation by the neophyte airplane builder. If there
were a Schottky based product available in the same package, it would
indeed be more attractive if one wished to "quibble" over a 5-watt
differential under operating conditions where the system has plenty
of watts to burn. However, since "watts" are not significant, it seems
more practical to concentrate on mechanical features that made it easy
for the OBAM aircraft builder to implement an e-bus in his project with a
minimum cost and risk.
Bob . . .
Message 20
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| Subject: | Re: Rocker Switch Problems-Followup |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 09:40 AM 6/4/2004 -0700, you wrote:
>--> AeroElectric-List message posted by: "Scott Diffenbaugh"
><diff@foothill.net>
>
<snip>
> I checked out the "TP" switches. They would require a major
> rework of my
>panel. Looks like I will have the operators re-engraved on the upper half
>and live with it. Thanks again. Scott
One last note. The part number you quoted has an "FBA" phrase
which indicates no lamp installed. If you want some 12 lamps
installed, you'll need the "FBC" series switches.
Bob . . .
Message 21
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<Aeroelectric-List@matronics.com> (Aeroelectric-List)
| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: jmfpublic@comcast.net
Listers,
This topic just illustrates how difficult it is to discuss OBAM electrical systems.
There are so many ways of operating the system, and so many choices to make.
I'm with Bob on this thread, as the power drop through the diode while on
alternator power is, to me, negligible. Recall that Bob wrote the 'Connection
over a period of years, and Schottky diodes have been rare until recently.
As he pointed out above, the e-bus sees no diode drop on battery power because
the pilot turns on the battery to e-bus switch. Thus, calculating the "lost"
available power while on battery only operation is not applicable, as there
is _no_ diode drop at this time.
Of course, after safety, there is aesthetics for those with the time and inclination.
The OBAM aircraft lets you make these choices, and you are more likely
to understand how to use your craft in an emergency having participated in this
thought process.
Jim Foerster J400, ready to wire.
Message 22
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: echristley@nc.rr.com
> No worries. I get a chuckle out of it. Heck, my
nickname in
> elementary school was "Mr. Brain". I was the
nerdy guy who brought
> books on rocket engine design or the Radio
Amateur's Handbook to
> school instead of the Hardy Boys.
>
Way off topic but...
You're obviously from a different era than I.
I was the "Mr. Brain" at my school. I was the nerdy
guy who brought the Hardy Boys.
do not archive
Message 23
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--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
Will all those aeroelectric-listers who had the nickname "Mr. Brain" in
school please raise their hands?
Regards,
Eric M. Jones (Mr. Brain)
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones@charter.net
Message 24
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| Subject: | Re: Mr. Brain OT |
--> AeroElectric-List message posted by: Harley <harley@agelesswings.com>
Sorry...I was "Wizard" ...<G>
Harley Dixon
Eric M. Jones wrote:
>--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
>
>Will all those aeroelectric-listers who had the nickname "Mr. Brain" in
>school please raise their hands?
>
>Regards,
>Eric M. Jones (Mr. Brain)
>www.PerihelionDesign.com
>113 Brentwood Drive
>Southbridge MA 01550-2705
>Phone (508) 764-2072
>Email: emjones@charter.net
>
>
>
>
Message 25
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--> AeroElectric-List message posted by: "David Glauser" <david.glauser@xpsystems.com>
Heh. "Dr. Dave".
dg
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Harley
Subject: Re: AeroElectric-List: Mr. Brain OT
--> AeroElectric-List message posted by: Harley
--> <harley@agelesswings.com>
Sorry...I was "Wizard" ...<G>
Harley Dixon
Eric M. Jones wrote:
>--> AeroElectric-List message posted by: "Eric M. Jones"
>--> <emjones@charter.net>
>
>Will all those aeroelectric-listers who had the nickname "Mr. Brain" in
>school please raise their hands?
>
>Regards,
>Eric M. Jones (Mr. Brain)
>www.PerihelionDesign.com
>113 Brentwood Drive
>Southbridge MA 01550-2705
>Phone (508) 764-2072
>Email: emjones@charter.net
>
>
>
>
==
direct advertising on the Matronics Forums.
==
==
==
Message 26
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
----- Original Message -----
From: "Brian Lloyd" <brianl@lloyd.com>
Subject: Re: AeroElectric-List: Re: Power Diode Drops
> The point that your xpdr and comm will transmit with higher power is a
good one. Since you will directly connect your e-buss to the battery in the
case of alternator failure, the end-point voltage relative to diode drop is
a non-issue.
>
Why would I need to do that. Its an extra switch possibly a CB and its a
direct battery connection that needs to be special wiring etc.
Use the right diode and there is no reason for such an extra switch. Also
then one needs to rememner its a direct connection to the battery and one
more thing to be sure is off when shutting down.
In my design I do nothing beyond diverting to the closest airport in the
case of an alternator failure. No special switches to fool with, no
additional cockpit load.
Paul
Message 27
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| Subject: | Re: Mr. Brain OT |
--> AeroElectric-List message posted by: Chad Robinson <crj@lucubration.com>
Eric M. Jones wrote:
> --> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
>
> Will all those aeroelectric-listers who had the nickname "Mr. Brain" in
> school please raise their hands?
What about nerd?
Message 28
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| Subject: | Re: Digital Music in the Cockpit |
--> AeroElectric-List message posted by: frequent flyer <jdhcv@yahoo.com>
Let me reveal my age and my lack of knowledge. just
exactly what is an ipod? How does it differ from a PDA
or a palm pilot? How do you transfer music to it?
See, now you know about me.
Jack
do not archive
--- Dan Checkoway <dan@rvproject.com> wrote:
> --> AeroElectric-List message posted by: "Dan
> Checkoway" <dan@rvproject.com>
>
> ipod! I have a 15gb ipod that rocks the house.
__________________________________
http://messenger.yahoo.com/
Message 29
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
From: <jmfpublic@comcast.net>
<Aeroelectric-List@matronics.com>
Subject: AeroElectric-List: Re: Power Diode Drops
Recall that Bob wrote the 'Connection over a period of years, and Schottky
diodes have been rare until recently. As he pointed out above, the e-bus
sees no diode drop on battery power because the pilot turns on the battery
to e-bus switch. Thus, calculating the "lost" available power while on
battery only operation is not applicable, as there is _no_ diode drop at
this time.
I have had the power schottky diode I am discussing for at least 5 years and
it was not a new design then and in distributor stock at that time. So I
disagree that good and easy to use parts were rare even 5 years ago and more
likely 10 years ago. It does take some time to see what is out there which
is harder to do than going to RS and picking a part off the shelf.
If you go back further Schottky stud diodes have been avaiulable for many
many years and a simple thru hole insulated mount is simple and also off the
shelf. Hardly difficult to do.
As for turning on the e-bus switch consider that with the RS bridge such a
switch is needed.
With a proper Schottky diode there is no need for such a switch or the need
for the pilot to remember to turn it on. Or off later
I have not looked the latest designs in the "Book" but hopefully the
alternator failing does not cause power on the e-bus to fail and the only
reason for such a switch is to get the last of the power from the battery.
BY the way, Hopefully this is not a contest where people take sides and the
most votes wins. It should be open to all ideas and rather than pick at new
ideas consider are that is it just different or is there real advantages. I
would pick a simple no mechanical switch with no addl wiring approach that
was automatic over the switch. This does mean a different design than that
supported by the "Book"
I am not suprised (but disappointed) at the flack this thread is getting. I
was hoping that anything that simplified the electrical design and pilot
work load was an advantage, even if it required some fresh thinking at the
existing aproach.
Comments from many seem to zero in on "because the pilot throws a switch in
an existing design there is no advantage"... and miss the bigger picture
there is no need for the switch in a different, and I submit, better design.
Paul
Message 30
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
> . . . you're still missing the point. The manner in which an
> e-bus normal feed diode is used never causes BATTERY energy to flow
> through the diode to the E-bus.
In your latest design but not in many designs including mine.
> The diode bridge rectifier was chosen because of its ease of mounting
> (has mounting hole, needs no electrical insulation from airframe) and
> ease of connection (fast-on terminals). The selection wasn't based on
> electrical performance . . . electrical performance was not
> significant. This product was selected because it was inexpensive,
> readily available from dozens of off-the-shelf sources, and easy to
> mount. This device has a very high order probability of
> successful implementation by the neophyte airplane builder. If there
> were a Schottky based product available in the same package,
But it is available in a simple bolt down no insulation and bolt on lugs Not
exactly the same package but very simple to do.
> it would
> indeed be more attractive if one wished to "quibble" over a 5-watt
> differential under operating conditions where the system has plenty
> of watts to burn. However, since "watts" are not significant, it seems
> more practical to concentrate on mechanical features that made it easy
> for the OBAM aircraft builder to implement an e-bus in his project
with a
> minimum cost and risk.
Again you presume a design where additional switch(s) are needed to switch
over to direct battery feed. Hopefully you will agree that lower cockpit
pilot load and fewer connections and switches to throw is better and more
reliable in a real world situation where automatic power routing is more
likely to happen than manual thinking in a rare emergency.
Two truely independent batteries each feeding the e-bus thru a Schottky
diode provides switchless reliable (more reliable than extra wiring and a
switch in my opinion) e-bus power at minimal voltage loss and more
importantly its automatic. IE no pilot work load.
I am not "quibbling" over 5 watts. I am "quibbling" over the basic design
approach that seems to need a direct electrical connection to the battery
and bypassing the battery master contactor simply because of the
availability of a low v drop diode.
There was a long and thread about the need for keeping the current draw low
the the in any direct battery connections.
But why debate it, let each person decide for themselves. There are several
good solutions to every problem and we should direct our attention to the
many bad ones rather than try to justify one above other good solutions.
Paul
Message 31
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: "Phil Birkelbach" <phil@petrasoft.net>
What kind of architecture are you talking about? If you plan to simply
divert then it seems to me that you don't need the e-buss or the diode at
all.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Panel
http://www.myrv7.com
----- Original Message -----
From: "Paul Messinger" <paulm@olypen.com>
Subject: Re: AeroElectric-List: Re: Power Diode Drops
> --> AeroElectric-List message posted by: "Paul Messinger"
<paulm@olypen.com>
>
>
> ----- Original Message -----
> From: "Brian Lloyd" <brianl@lloyd.com>
> To: <aeroelectric-list@matronics.com>
> Subject: Re: AeroElectric-List: Re: Power Diode Drops
>
>
> > The point that your xpdr and comm will transmit with higher power is a
> good one. Since you will directly connect your e-buss to the battery in
the
> case of alternator failure, the end-point voltage relative to diode drop
is
> a non-issue.
> >
>
> Why would I need to do that. Its an extra switch possibly a CB and its a
> direct battery connection that needs to be special wiring etc.
>
> Use the right diode and there is no reason for such an extra switch. Also
> then one needs to rememner its a direct connection to the battery and one
> more thing to be sure is off when shutting down.
>
> In my design I do nothing beyond diverting to the closest airport in the
> case of an alternator failure. No special switches to fool with, no
> additional cockpit load.
>
> Paul
>
>
Message 32
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| Subject: | Re: Digital Music in the Cockpit |
--> AeroElectric-List message posted by: Chad Robinson <crj@lucubration.com>
frequent flyer wrote:
> --> AeroElectric-List message posted by: frequent flyer <jdhcv@yahoo.com>
>
> Let me reveal my age and my lack of knowledge. just
> exactly what is an ipod? How does it differ from a PDA
> or a palm pilot? How do you transfer music to it?
http://www.apple.com/ipod/
http://www.apple.com/ipod/specs.html
An iPod is a 4"x2.5"x.75" (largest unit) device that weighs about 6oz. and can
store about 4,000 songs. Depending on how much music you have in your
collection this could in many cases be your entire library. Units with more
storage capacity are also available for music freaks that want to "take it all
with them" (like me, although I use a different player).
The basic concepts and some photos are all in the URLs above. If your music is
on CDs you can use "ripping" software to copy it onto the iPod. You can also
download music from various sources, with various legal implications depending
on where you go. I suspect you don't plan any illegal music downloads; if you
don't know what an Ipod is you probably don't know where to go to GET illegal
music. =) Anything that you own and is on your shelf is fair game, so don't
worry too much about that bit.
If your music is in tape or other "analog" format you have to do a bit more
work - basically you hook your stereo up to your computer and record the items
you want to transfer. The benefit of doing this is that you have a digital
backup at that point that won't deteriorate over time.
The benefits for travel are also fairly significant - one small, lightweight
device can hold an enormous amount of music. Unlike a CD player/changer you
can slice/dice the music various ways using a tool called "playlists" so you
can have song collections to fit various moods or the people you're with.
The iPod is not the only such device. The name for this class of product is
"MP3 Player" and there are dozens of options on the market now. Aside from
car-focused products like the Empeg/Rio (which I use, but it's almost a
dinosaur now; my wife, who has an iPod, snickers at me because I'm still a Rio
fan) and the Phatbox, the iPod is probably the most expensive
consumer-oriented MP3 player on the market. It sells because it has a very
easy-to-use user interface, has a highly-rated tool for loading the player
with songs, is reliable, etc. That doesn't mean you shouldn't consider other
options, but if you have the cash and you don't know what you're doing you may
as well buy quality.
Regards,
Chad
Message 33
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| Subject: | Re: Power Diode Drops |
--> AeroElectric-List message posted by: Kevin Horton <khorton01@rogers.com>
>--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
>
>----- Original Message -----
>From: "Brian Lloyd" <brianl@lloyd.com>
>To: <aeroelectric-list@matronics.com>
>Subject: Re: AeroElectric-List: Re: Power Diode Drops
>
>
> > The point that your xpdr and comm will transmit with higher power is a
>good one. Since you will directly connect your e-buss to the battery in the
>case of alternator failure, the end-point voltage relative to diode drop is
>a non-issue.
> >
>
>Why would I need to do that. Its an extra switch possibly a CB and its a
>direct battery connection that needs to be special wiring etc.
I guess it depends on how far you have to go to get to the airport. If the
airport is close, then it doesn't make any difference. But if you have a
fair ways to go you will want to shed the Main Bus loads to allow longer
battery duration, which means that the feed through the diode is no longer
functioning.
>Use the right diode and there is no reason for such an extra switch. Also
>then one needs to rememner its a direct connection to the battery and one
>more thing to be sure is off when shutting down.
Normally, the E-bus alternate feed would not have been selected, so this
isn't a consideration.
>In my design I do nothing beyond diverting to the closest airport in the
>case of an alternator failure. No special switches to fool with, no
>additional cockpit load.
There are a lot of parts of the world where you could be more than an hour
from the closest airport. How long will you battery last if you are
running all your loads? It is easier to flip two switches to select the
E-bus alternate feed and deselect the battery contactor than it is to
manually shed main bus loads. Plus it is nice to shed the battery
contactor load if you have lost the alternator.
Kevin Horton
RV-8 (Finishing Kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
Message 34
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<Aeroelectric-List@matronics.com> (Aeroelectric-List)
| Subject: | Re: Re: Power Diode Drops |
--> AeroElectric-List message posted by: jmfpublic@comcast.net
Paul Messinger wrote in response to Bob:
> . . . you're still missing the point. The manner in which an
> e-bus normal feed diode is used never causes BATTERY energy to flow
> through the diode to the E-bus.
"In your latest design but not in many designs including mine."
Paul, recall that this discussion started on May 31 with Arthur Treff noting that
he had a 1 volt drop to his e-bus through his silicon diode. Arthur noted
that he used diagram Z13, the "all electrical system on a budget." With this
system, if I recall, alternator failure is announced via a low voltage alarm.
The pilot then turns off the battery master contactor, saving that power and
simultaneously cutting off non-essential lighting and loads that can be abandoned.
He also turns on the e-bus to battery switch, maintaining the desired list
of items necessary to complete the flight to the destination.
If you change the architecture, i.e. the schematic, then operation will be different.
I believe that some of us in this discussion thought you were still referring
to the Z13 diagram.
Of course you are right that the Schottky is the desirable choice for battery only
operation where the power goes through the diode. I, too, would prefer that
the pilot not need to throw a switch to maintain the e-bus. However, if you
use two independent batteries to power the e-bus, you would need to have an
avionics master switch that would need to be turned off at the end of the flight,
and also represents a single point of failure. Or have you figured out a
more clever arrangement?
Also, thanks for your measurements of the diode voltage drops at various currents.
Your work with the "load dump" issue is appreciated,too.
Jim Foerster J400, 80%...
Message 35
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| Subject: | Re: AeroElectric-List Digest: 32 Msgs - 06/03/04 |
--> AeroElectric-List message posted by: "Dave Ford" <dford@michweb.net>
>I now have an Apple iPod. This is the most fantastic device for playing
music
in the cockpit I have ever found. My entire record and CD collection fits
on
the thing with plenty of room left over for more music in the future. I
don't
need to fumble around with cassettes, CDs, minidisks, or memory cards. Not
only
that but the song you want is always right there. I highly recommend this
as the best solution for portable music in the cockpit.
I think I like the idea of having a lot of music on one device but I can't
see me sitting for hours loading this thing full of music--or is there a
better way? How much time do you have putting your entire collection on
your iPod? Also is there a good website for picking out one of these
devices? I have tried a search for this but end up running in circles.
Dave Ford
RV6
Message 36
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| Subject: | Re: Digital Music in the Cockpit |
--> AeroElectric-List message posted by: frequent flyer <jdhcv@yahoo.com>
Chad, Great info. Thanks for the reply.
Jack
--- Chad Robinson <crj@lucubration.com> wrote:
> --> AeroElectric-List message posted by: Chad
> Robinson <crj@lucubration.com>
>
>
> http://www.apple.com/ipod/
> http://www.apple.com/ipod/specs.html
>
> An iPod is a 4"x2.5"x.75" (largest unit) device that
> weighs about 6oz. and can
> store about 4,000 songs.
__________________________________
http://messenger.yahoo.com/
Message 37
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| Subject: | Re: Digital Music in the Cockpit |
--> AeroElectric-List message posted by: frequent flyer <jdhcv@yahoo.com>
Chad, Great info. Thanks for the reply.
Jack
do not archive
--- Chad Robinson <crj@lucubration.com> wrote:
> --> AeroElectric-List message posted by: Chad
> Robinson <crj@lucubration.com>
>
>
> http://www.apple.com/ipod/
> http://www.apple.com/ipod/specs.html
>
> An iPod is a 4"x2.5"x.75" (largest unit) device that
> weighs about 6oz. and can
> store about 4,000 songs.
__________________________________
http://messenger.yahoo.com/
Message 38
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| Subject: | Re: Digital Music in the Cockpit |
--> AeroElectric-List message posted by: richard@riley.net
The IPOD hard disk tends to head crash above 10,000 feet with just a touch
of turbulence. I found out the hard way
"
Environmental requirements
* Operating temperature: 32 to 95 F (0 to 35 C)
* Non operating temperature: -4 to 113 F (-20 to 45 C)
* Relative humidity: 5% to 95% noncondensing
* Maximum operating altitude: 10,000 feet (3000 m)
At 03:20 PM 6/4/04, you wrote:
>--> AeroElectric-List message posted by: Chad Robinson <crj@lucubration.com>
>
>frequent flyer wrote:
> > --> AeroElectric-List message posted by: frequent flyer <jdhcv@yahoo.com>
> >
> > Let me reveal my age and my lack of knowledge. just
> > exactly what is an ipod? How does it differ from a PDA
> > or a palm pilot? How do you transfer music to it?
>
>http://www.apple.com/ipod/
>http://www.apple.com/ipod/specs.html
>
>An iPod is a 4"x2.5"x.75" (largest unit) device that weighs about 6oz. and
>can
>store about 4,000 songs. Depending on how much music you have in your
>collection this could in many cases be your entire library. Units with more
>storage capacity are also available for music freaks that want to "take it
>all
>with them" (like me, although I use a different player).
>
>The basic concepts and some photos are all in the URLs above. If your
>music is
>on CDs you can use "ripping" software to copy it onto the iPod. You can also
>download music from various sources, with various legal implications
>depending
>on where you go. I suspect you don't plan any illegal music downloads; if you
>don't know what an Ipod is you probably don't know where to go to GET illegal
>music. =) Anything that you own and is on your shelf is fair game, so don't
>worry too much about that bit.
>
>If your music is in tape or other "analog" format you have to do a bit more
>work - basically you hook your stereo up to your computer and record the
>items
>you want to transfer. The benefit of doing this is that you have a digital
>backup at that point that won't deteriorate over time.
>
>The benefits for travel are also fairly significant - one small, lightweight
>device can hold an enormous amount of music. Unlike a CD player/changer you
>can slice/dice the music various ways using a tool called "playlists" so you
>can have song collections to fit various moods or the people you're with.
>
>The iPod is not the only such device. The name for this class of product is
>"MP3 Player" and there are dozens of options on the market now. Aside from
>car-focused products like the Empeg/Rio (which I use, but it's almost a
>dinosaur now; my wife, who has an iPod, snickers at me because I'm still a
>Rio
>fan) and the Phatbox, the iPod is probably the most expensive
>consumer-oriented MP3 player on the market. It sells because it has a very
>easy-to-use user interface, has a highly-rated tool for loading the player
>with songs, is reliable, etc. That doesn't mean you shouldn't consider other
>options, but if you have the cash and you don't know what you're doing you
>may
>as well buy quality.
>
>Regards,
>Chad
>
>
Message 39
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| Subject: | B&C LR-3C question |
--> AeroElectric-List message posted by: "Emrath" <emrath@comcast.net>
Would putting the resistor in the circuit (or the two 220 ohm resistors as
Bob suggests) stop the current leak to the point where there is no battery
drain when hangered?
Marty
Time: 08:32:50 PM PST US
From: "James Redmon" <james@berkut13.com>
Subject: AeroElectric-List: B&C LR-3C question
--> AeroElectric-List message posted by: "James Redmon" <james@berkut13.com>
All,
I was working with B&C on this, but the gentleman is out of pocket for a
couple weeks and thought one of you might know the answer.
I am using a LED instead of an incandescent lamp for the OV light. The
issue I discussed with B&C was that the LED never goes out...it stays on
(dimly) even when the regulator is turned off. When I turn on the regulator
(battery only) the LED does blink properly. He mentioned that the regulator
bleeds a little current on the lamp pin all the time - not enough to
illuminate a lamp, but a LED still glows slightly.
He mentioned a fix of placing a 520-ohm resistor between Pin 5 (the lamp
lead) and another pin on the regulator. I have misplaced my notes and can
not remember specifically which other pin to connect the resistor to.
Does someone happen to know which one I should use? If not, I can always
wait a
couple of weeks until Tim gets back.
Thanks!
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
Message 40
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| Subject: | Re: AeroElectric-List Digest: 32 Msgs - 06/03/04 |
--> AeroElectric-List message posted by: Chad Robinson <crj@lucubration.com>
Dave Ford wrote:
> I think I like the idea of having a lot of music on one device but I can't
> see me sitting for hours loading this thing full of music--or is there a
> better way? How much time do you have putting your entire collection on
> your iPod? Also is there a good website for picking out one of these
> devices? I have tried a search for this but end up running in circles.
Well, that's a somewhat loaded question. If you only have one CD, if you
download my favorite ripping tool (CDex, a free application that will even
look up and name your files for you), if you don't make a lot of playlists, in
10-15 minutes you could have that disc on your iPod. Add a few minutes more
for each additional disc once you get the hang of it.
So it all depends on:
* How much music can FIT on your player. Some players like the iPod use
hard drives and can store thousands of files. That would take a while
to transfer, perhaps hours if you did it all at once. Some players,
like the more portable armband-style Flash-based units can only fit
10-20 songs, so they're not much more than small, light, skip-free CD
player replacements. Those wouldn't take long at all to load.
* How much music you have. If you just bought your first CD, it won't
take long at all. =) Also, although I suggested earlier that it's
possible to convert old analog (tape and phono) sources I don't
generally recommend doing this unless you're a stereophile and
comfortable with the signal side of things. These sources generally
need quite a bit of cleaning up to be usable.
* Your level of comfort with computers. There's no shame in admitting
inexperience here. If this is the case you should definitely consider
a product with a highly-rated user interface, like the iPod. I also
recommend buying from a local store rather than online because it's
easier to return if you decide you don't like it.
* How much you really CARE about aesthetics. I use my MP3 player
constantly, so I spent a lot of time tweaking playlists, song
title, artist, genre, etc. information, and so on. I spent WEEKS
doing this, but I chose to - it wasn't actually necessary. If you're
the type who rarely even takes the CD booklet out of the jewel case
to see what's inside, you can skip this process.
How much time? Well, I own over 600 CDs, all legally. I have spent HUNDREDS of
hours ripping, categorizing, and manipulating these songs for use on four
different MP3 players through the years. My wife has spent probably 20 hours
on her iPod, and a buddy of mine spent about 10 minutes - dragged-and-dropped
a few files, and walked away while they copied over.
By the way, if you do go this route there's a hidden benefit. I keep all my
files in a shared folder on my home network. I haven't touched a CD (except to
import new purchases) in several years. They're all sitting in boxes in the
attic. CDs are HUGE! I've seen people with enormous shelving units for them.
All that disappeared for me.
In terms of device selection, I always drop by http://www.epinions.com and
http://www.amazon.com to read reviews before I buy consumer electronics (or
other things!) You have to take reviews with a grain of salt - people with
problems tend to be more vocal than those without. But, at least it gives you
a general feeling for what you might expect, battery lifetimes, quality of
support options, etc. http://www.pricewatch.com is a good place to go for
price comparisons, too.
Regards,
Chad
Message 41
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| Subject: | Re: B&C LR-3C question |
--> AeroElectric-List message posted by: "James Redmon" <james@berkut13.com>
Sure...as long as you remember to turn the master off. ;-)
(I couldn't resist)
-James
Do not archive
> Would putting the resistor in the circuit (or the two 220 ohm resistors as
> Bob suggests) stop the current leak to the point where there is no battery
> drain when hangered?
> Marty
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