Today's Message Index:
----------------------
1. 05:53 AM - (bob noffs)
2. 06:29 AM - Re: (Harley)
3. 06:57 AM - Re: Right angle "cannon" connector (Robert L. Nuckolls, III)
4. 08:28 AM - Re: (Jim Wickert)
5. 03:08 PM - Understanding Alternators (Tinne maha)
6. 03:19 PM - Variac (Tinne maha)
7. 03:51 PM - Re: Variac (Bob White)
8. 04:03 PM - Re: (Greg Young)
9. 05:39 PM - Re: Variac (Boddicker)
10. 06:02 PM - Re: Variac (Charlie England)
11. 06:14 PM - Apollo GX65 GPS/Comm ()
12. 06:51 PM - Z-11 questions (Robert L. Nuckolls, III)
13. 07:40 PM - Re: Turn Coordinator Connector (Robert L. Nuckolls, III)
14. 07:46 PM - Bench and ground power supply (Robert L. Nuckolls, III)
15. 07:53 PM - Re: Variac (Robert L. Nuckolls, III)
16. 08:08 PM - Re: Understanding Alternators (Robert L. Nuckolls, III)
17. 08:19 PM - Re: Risks to Deltran Battery Tender Jr. (Robert L. Nuckolls, III)
18. 08:26 PM - Re: Electronic Ignition Problem (Robert L. Nuckolls, III)
Message 1
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--> AeroElectric-List message posted by: "bob noffs" <icubob@newnorth.net>
hi all,
i am looking for a source of ''cannon'' elect. fittings. i understand this is
military stuff. my turn coor. came fitted for this typa of elect. connection and
i need a 90 deg. fitting for my limited clearance.
thanks, bob noffs
Message 2
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Subject: | Re: ectric-List: |
--> AeroElectric-List message posted by: Harley <harley@agelesswings.com>
Morning, Bob...
Cannon makes electrical terminals and connection components for industry
as well...they also have mil spec products but that may not be needed in
your case.
Most good electrical supply houses stock them. A good place to start
looking for the part you are looking for would be Cannon's home page, here:
www.peigenesis.com/ittCannon_products.html
Then, when you know the part number you are looking for, you can google
it and find a supplier.
Or, someone else reading this may know EXACTLY what you are looking for
and save you the search time!
Harley Dixon
bob noffs wrote:
>--> AeroElectric-List message posted by: "bob noffs" <icubob@newnorth.net>
>
>hi all,
> i am looking for a source of ''cannon'' elect. fittings. i understand this is
military stuff. my turn coor. came fitted for this typa of elect. connection
and i need a 90 deg. fitting for my limited clearance.
> thanks, bob noffs
>
>
>
>
Message 3
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Subject: | Re: Right angle "cannon" connector |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 07:51 AM 11/6/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: "bob noffs" <icubob@newnorth.net>
>
>hi all,
> i am looking for a source of ''cannon'' elect. fittings. i understand
> this is military stuff. my turn coor. came fitted for this typa of elect.
> connection
The term "cannon connectors" was coined to describe the MS3100 series
connectors that showed up in great volumes in WWII.
By the time I first hammered on airplanes at Boeing in '61, the
new "cannon" connector was a miniature connector that utilized
crimped, removable pins. I don't think these caught on. They're
not in the current catalog.
Bottom line is that ITT-Cannon (and many others) make a variety
of connectors that have all been referred to as "cannon" connectors
at some point in time.
Can you find a part number stamped on the connector you're trying
to replace or the connector it mates with?
Here's a catalog of current offerings by ITT-Cannon. Start with
the MS3102 series on p167.
http://www.ittcannon.com/media/pdf/catalogs/full/CO_milaero.pdf
Theres an intermatable 3450 series on p188.
>and i need a 90 deg. fitting for my limited clearance.
You may find that the exact connector you need is long lead
time or not even available as a catalog item for quantities
of one. The last ditch solution may be to remove the backshell
from the connector you have and use some E-6000 to provide
strain relief by "potting" the wires to the connector. Not
terribly elegant but very suited to the task.
Bob . . .
Message 4
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Subject: | Re: ectric-List: |
--> AeroElectric-List message posted by: Jim Wickert <jimw_btg@earthlink.net>
Bob
Jim Wickert here, you can get Cannon Mil spec connectors from Newark Electronics. I have an older cat and they are listed on page 1265 but you can find Newark at www.Newark.com. Also I am not sure where you are located but if you have a Motion Industries, or a Minarik Automation & control, located near you they will have them as well. I believe Allied Electronics has Mil spec connectors not sure if they have Cannon?
Happy building
Jim Wickert
Vision Vair #159
-----Original Message-----
From: bob noffs <icubob@newnorth.net>
Subject: AeroElectric-List:
--> AeroElectric-List message posted by: "bob noffs" <icubob@newnorth.net>
hi all,
i am looking for a source of ''cannon'' elect. fittings. i understand this is
military stuff. my turn coor. came fitted for this typa of elect. connection and
i need a 90 deg. fitting for my limited clearance.
thanks, bob noffs
Message 5
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Subject: | Understanding Alternators |
--> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
Hi Bob & List,
I was out of town for a while, but just got done reading your work in
progress on understanding alternators. Thank You! A fresh review of basic
physics with a slant towards aviation applications like this give me better
understanding & more confidence in what I'm doing.
As for corrections, I've only got two small typos:
-First page, first paragraph, fifth sentence.....change from 'This photo is
illustrates.....' to 'This photo illustrates'
-Fourth page, below the graph, under the heading 'Minimum Speed for
Regulation': Last two sentences of first paragraph.....review for intended
meaing. I believe you wanted to last two sentences to be one. I don't
think you meant to leave 'As RPM increases from Zero.' as one sentence.
Message 6
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--> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
I'm getting ready to connect my battery to the electrical system & need
advice on two simple matters:
- Any ideas on where to get a Variable voltage device? My strobe power
supply has been setting for a few years. As such, Whelen's tech strongly
suggested that I connect it to a variable voltage device (Isn't that a
variac?), set it at 3 Volts for 15 minutes, 6 Volts for 15 minutes, 9 Volts
for 15 minutes & finally 12 Volts. As a side question out of curiosity,
what does this do?
- I'm looking for a 0.5 amp 'blade type' (ATC?) fuse to power my Ipod. The
smallest one I see on the B&C website is 1.0 amps. Any suggestions? Are
auto fuses the same size? Any reason not to use one from an auto parts
store?
Thanks,
Grant
Message 7
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--> AeroElectric-List message posted by: Bob White <bob@bob-white.com>
A Variac is a variable transformer, an AC device. You need a variable
DC power supply. Likely sources are eBay or your local electronic
supply. I searched Radio Shack. I would have expected them to have
one, but all I could find were fixed voltage supplies.
I have no idea why they want you to do that unless it might have
something to do with conditioning electrolytic capacitors in the unit.
Bob W.
On Sun, 06 Nov 2005 15:18:26 -0800
"Tinne maha" <tinnemaha@hotmail.com> wrote:
> --> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
>
> I'm getting ready to connect my battery to the electrical system & need
> advice on two simple matters:
>
> - Any ideas on where to get a Variable voltage device? My strobe power
> supply has been setting for a few years. As such, Whelen's tech strongly
> suggested that I connect it to a variable voltage device (Isn't that a
> variac?), set it at 3 Volts for 15 minutes, 6 Volts for 15 minutes, 9 Volts
> for 15 minutes & finally 12 Volts. As a side question out of curiosity,
> what does this do?
>
>
> - I'm looking for a 0.5 amp 'blade type' (ATC?) fuse to power my Ipod. The
> smallest one I see on the B&C website is 1.0 amps. Any suggestions? Are
> auto fuses the same size? Any reason not to use one from an auto parts
> store?
>
> Thanks,
> Grant
>
>
>
>
>
>
>
>
--
http://www.bob-white.com
N93BD - Rotary Powered BD-4 (projected engine start in November)
Custom Cables for your rotary installation -
http://www.roblinphoto.com/shop/
Message 8
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--> AeroElectric-List message posted by: "Greg Young" <gyoung@cs-sol.com>
Have you tried Aircraft Spruce, Chief, etc.? Spruce carries:
CANNON PLUG MS3106A-10SL-3S $11.20
CABLE CLAMP MS3057-4A $2.95
It's what I bought when I found my T/C wired without a plug. They may
very well have the right angle as well. At least you can use the
straight p/n to find the right angle in the same series.
Greg Young
>
> --> AeroElectric-List message posted by: "bob noffs"
> --> <icubob@newnorth.net>
>
> hi all,
> i am looking for a source of ''cannon'' elect. fittings. i
> understand this is military stuff. my turn coor. came fitted
> for this typa of elect. connection and i need a 90 deg.
> fitting for my limited clearance.
> thanks, bob noffs
Message 9
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--> AeroElectric-List message posted by: Boddicker <trumanst@netins.net>
Grant,
The folks from Whelen told me to do the same. It brings the capacitors (sp)
back to a usable state. If you put the full voltage to them it may do harm.
I did each step up for one hour, not 15 min. That was the recomendation from
Whelen, and it worked just fine. I borrowed a voltage controller from a
friend. The variac I used to hot wire was 110 V. The unit you need for this
is 12V.
Kevin
on 11/6/05 5:18 PM, Tinne maha at tinnemaha@hotmail.com wrote:
> --> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
>
> I'm getting ready to connect my battery to the electrical system & need
> advice on two simple matters:
>
> - Any ideas on where to get a Variable voltage device? My strobe power
> supply has been setting for a few years. As such, Whelen's tech strongly
> suggested that I connect it to a variable voltage device (Isn't that a
> variac?), set it at 3 Volts for 15 minutes, 6 Volts for 15 minutes, 9 Volts
> for 15 minutes & finally 12 Volts. As a side question out of curiosity,
> what does this do?
>
>
> - I'm looking for a 0.5 amp 'blade type' (ATC?) fuse to power my Ipod. The
> smallest one I see on the B&C website is 1.0 amps. Any suggestions? Are
> auto fuses the same size? Any reason not to use one from an auto parts
> store?
>
> Thanks,
> Grant
>
>
>
>
>
>
Message 10
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--> AeroElectric-List message posted by: Charlie England <ceengland@bellsouth.net>
Tinne maha wrote:
>--> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
>
>I'm getting ready to connect my battery to the electrical system & need
>advice on two simple matters:
>
>- Any ideas on where to get a Variable voltage device? My strobe power
>supply has been setting for a few years. As such, Whelen's tech strongly
>suggested that I connect it to a variable voltage device (Isn't that a
>variac?), set it at 3 Volts for 15 minutes, 6 Volts for 15 minutes, 9 Volts
>for 15 minutes & finally 12 Volts. As a side question out of curiosity,
>what does this do?
>
>
>- I'm looking for a 0.5 amp 'blade type' (ATC?) fuse to power my Ipod. The
>smallest one I see on the B&C website is 1.0 amps. Any suggestions? Are
>auto fuses the same size? Any reason not to use one from an auto parts
>store?
>
>Thanks,
> Grant
>
Others have answered about the variac.
Normally, fuses in the aircraft (or home, for that matter) are intended
to protect wire, not devices. The Ipod won't draw more current than it
was designed for unless it's already broken. The ATC fuses are a bit
more reliable than the old glass fuses, but 'nuisance' blowing can be a
problem with extremely low current fuses. Why not just fuse at normal
rating for that wire?
Charlie
Message 11
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Subject: | Apollo GX65 GPS/Comm |
--> AeroElectric-List message posted by: <bbradburry@allvantage.com>
If anyone is interested in a good GPS/Comm, my GX65 is listed for sale on
Ebay. The Item number: 4587492679.
Thanks,
Bill Bradburry
Message 12
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>Bob,
>I am looking at figure z-11. What is your opinion on putting two
>contactors forward of the firewall one for the main bus and the other for
>the emer. bus.
Why? What kind of loads are you putting on the endurance bus? You
should bring these loads down to the absolute minimum for the purpose
of conserving battery energy during alternator out ops. Adding a contactor
to switch the alternate feed path goes against the grain of energy
conservation,
adds complexity (reduces reliablity).
>I would still use the isolation diode. The only differecne that I see is
>that I would have two unfused wires running into the cabin instead of
>one. I am building a RV6 with the battery on the front side of the firewall.
Okay. Do you plan a battery bus? Are there any planned accessories
that would benefit from an always hot battery bus? You could bring
the battery bus feeder into the cockpit as an unfused. It would be
relatively small gage (16 should do it). Take some extra pains for
mechanical protection. Take the e-bus alternate feed from a 7A or
smaller fuse through the alternate feed switch.
>If a bridge is used for isolation should two diodes by put in parallel?
Wouldn't hurt but not necessary.
>Can you suggest a isolation diode that easier to mount (at least two holes)?
Don't know of any. If you want two holes, bond the diode Bridge to an
aluminum mounting plate (thick and hard . . . 0.060 or better, T4 or
better) with JB weld. Put as many mounting holes in base as you like.
Millions have been mounted with the single hole for over 40 years.
Bob . . .
Message 13
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Subject: | Turn Coordinator Connector |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 06:02 PM 11/6/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: "Greg Young" <gyoung@cs-sol.com>
>
>Have you tried Aircraft Spruce, Chief, etc.? Spruce carries:
>CANNON PLUG MS3106A-10SL-3S $11.20
>CABLE CLAMP MS3057-4A $2.95
>It's what I bought when I found my T/C wired without a plug. They may
>very well have the right angle as well. At least you can use the
>straight p/n to find the right angle in the same series.
>
>Greg Young
>
> >
> > --> AeroElectric-List message posted by: "bob noffs"
> > --> <icubob@newnorth.net>
> >
> > hi all,
> > i am looking for a source of ''cannon'' elect. fittings. i
> > understand this is military stuff. my turn coor. came fitted
> > for this typa of elect. connection and i need a 90 deg.
> > fitting for my limited clearance.
> > thanks, bob noffs
Bob,
My apologies. I didn't pick up on the turn coordinator
requirement and thought your request was more generic. If
the "straight" connector is indeed an MS3106B10SL3S then
a right angle version of the same connector is a
MS3108B10SL3S which http://Newark.com shows in stock as their catalog
number 96J9697. Check the dimensions for this connector
on page 178 of
http://www.ittcannon.com/media/pdf/catalogs/full/CO_milaero.pdf
where over all dim L3 is on the order of 2.2 inches (plus seating
height when installed on the turn coordinator. Will this be
sufficiently small to make your clearance requirements?
Bob . . .
Message 14
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Subject: | Bench and ground power supply |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
Just ran across this item on the 'net.
http://www.web-tronics.com/25ampswitpow.html
This supply is adjustable to 9-15 volts meaning that
you can set it to emulate an alternator at 14.2 volts.
Better yet, it's metered.
Bob . . .
Message 15
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 04:50 PM 11/6/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: Bob White <bob@bob-white.com>
>
>A Variac is a variable transformer, an AC device. You need a variable
>DC power supply. Likely sources are eBay or your local electronic
>supply. I searched Radio Shack. I would have expected them to have
>one, but all I could find were fixed voltage supplies.
>
>I have no idea why they want you to do that unless it might have
>something to do with conditioning electrolytic capacitors in the unit.
>
>Bob W.
That's the idea. I'm surprised they're still recommending this
procedure. It was a good idea 40 years ago but modern electrolytics
don't seem to benefit from it. In any case, the well fitted workbench
should have some kind of power supply for testing things. We have
more kinds of power supplies in our shop than any other piece of
test equipment. A good value in a metered bench supply is illustrated
on ebay right now. Search on item 7560349791.
You should be able to find a 0-30v, 3A, metered, current limited
power supply from a variety of sources for under $100.
Bob . . .
Message 16
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Subject: | Re: Understanding Alternators |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 03:07 PM 11/6/2005 -0800, you wrote:
>--> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
>
>Hi Bob & List,
>
>I was out of town for a while, but just got done reading your work in
>progress on understanding alternators. Thank You! A fresh review of basic
>physics with a slant towards aviation applications like this give me better
>understanding & more confidence in what I'm doing.
>
>As for corrections, I've only got two small typos:
>
>-First page, first paragraph, fifth sentence.....change from 'This photo is
>illustrates.....' to 'This photo illustrates'
>
>-Fourth page, below the graph, under the heading 'Minimum Speed for
>Regulation': Last two sentences of first paragraph.....review for intended
>meaing. I believe you wanted to last two sentences to be one. I don't
>think you meant to leave 'As RPM increases from Zero.' as one sentence.
Fixed 'em. Thanks for the heads-up. My boss is mumbling something
about sending me off to 'fix' an airplane that probably can't be
fixed. Might get to spend a few days on airplanes and in hotels
and get the next few pages ready to publish.
Bob . . .
Message 17
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Subject: | Re: Risks to Deltran Battery Tender Jr. |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>Question:
>
>Will the Deltran Battery Tender Jr. be at risk for damage due to
>long term connection to a battery that cannot be charged and/or
>has some fixed load across the battery that exceeds the rated output
>current of the charger?
>
This question offers and excellent opportunity to discuss
thermal modeling of an electronic device and to introduce
the concept of thermal resistance. To begin the discussion,
it was useful to conduct a simple test on the product.
Let's gather some rudimentary data on a Battery Tender Jr.
under extra-ordinary stress and see what we can deduce about
its operation and probability of survival:
The experiment . . .
Step 1: Connect Deltran Battery Tender Jr. across a 10 ohm resistor
paralleled with a 10,000 uF capacitor. Plug in wall.
Observation 1: Note that the Battery Tender does not come alive.
Hypothesis A: Circuitry in the charger senses whether or not
there is some semblance of a battery connected. Zero volts
could be either a dead short or a battery that is totally trashed.
The circuit is designed not to attempt a recharge cycle under
these conditions.
Step 2. Temporarily connect 12v battery across the load array.
Observation 2: Charger's red light comes on indicating that it
has gone to work.
Step 3. Connect voltmeter across the load array.
Observation 2: Voltmeter shows 10.2 volts across the load array.
Deduction: 10.2v at 10 ohms is right at 1.0 amp. The Deltran Battery
Tender Jr. is rated at 0.75A. Obviously, there are no features that
limit current to the rated value. This initial test setup has already
overloaded the device by 33%.
Step 4. Wait.
Observation 3: After an hour of operation, the case, particularly
next to the wall was pretty toasty. (Toasty: engineering term for
operating temperatures between "warm to touch" and "starting to
stink". The hottest surfaces were sides closest to the wall outlet.
Step 5. Add thermocouple to hottest surface and continue testing
Observation: 10 minutes after restart, case temperature is up to
65C.
Step 6. Wait.
Observation 4: After continuous operation overnight, the output
current from the Battery Tender was still holding at 1.05 amps.
The case temperature had stabilized at 69 degrees C in a 23 degree
C environment.
What might we deduce from this little bit of data and how
does it offer insight into the failure reported by John Huft.
Let's review his observations:
>--> AeroElectric-List message posted by: John Huft <aflyer@lazy8.net>
>
> Recently, I hooked up a Deltran charger (the junior, 0.75 Amp) to my
>wife's car, as I did all last winter. This time however, I left the hood
>open, with the underhood light on. The light draws more than the charger
>can source, so, when I returned a week later, the battery was dead. No
>surprising.
>
>The surprise, though, was that the charger was also dead. I took it
>apart, and saw that the output transistor, attached to a large heatsink,
>was a TO-220 package. There was no sign of an internal fuse (there is
>one in the battery lead, which was still good), so I assume there is a
>solid state type current limit circuit in the base of the output
>transistors. Having designed these circuits (I am assuming that it is
>not a crowbar type, but just a cheapo limiter), I know that they work
>well for momentary shorts, but if the short persists, the output
>transistor has to dissipate the rated current (.75A) times the voltage
>(14) totaling 10.5 Watts. The TO-220 package is usually a 5 Watt deal
>even with the heatsink, so I am thinking that is what killed the
>charger. I confess I have not tested anything...just returned the charger.
>
>Similarly, I would think a completely dead battery would present the
>same situation to the charger. So, I am thinking maybe the problem is
>not related to the battery at all, but rather to the charger????????
John's questions about over-heating of the major power handling
device in the charger is a good one. By the way John, if you still
have the smoked charger, I'd sure like to get my hands on it. Since
I didn't smoke the charger I used in the experiment, I'm reluctant
to saw it open for more detailed inspection . . . but if your dead
one is available, it would add some additional insight into the
functionality and vulnerabilities of this product.
Why didn't my Battery Tender smoke? Perhaps John's environment
was warmer. Perhaps his particular battery/load combination pulled
the charger's output lower than my experiment (10 volts) and caused
it to get hotter.
Given the temperature rise we measured, I'd estimate that my
experiment forced the Battery Tender into an internal dissipation
level on the order of 10 watts. It seems likely that long term
operation in this condition might put the critter at risk for
smoke.
I note that Deltran's instruction sheet for this charge does not
speak against charging large batteries (even a heavily discharged
battery will rise above 11 volts in under an hour). I've used
my Deltran BT Jr.s to recharge all sizes of batteries in every
state of discharge with good results.
I don't think we've learned anything from this experiment that
suggests my confidence and recommendations for use of the Deltran
BT Jr. needs modification. Our mini-investigation suggests that
the continuous, unintended loading of the battery was the proximate
cause of failure . . . and not a deficiency in the design of the
charger.
Bob . . .
Message 18
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Subject: | Re: Electronic Ignition Problem |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 04:18 PM 10/31/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "Stucklen, Frederic W UTPWR"
><Fred.Stucklen@UTCFuelCells.com>
>
>Listers,
>
> I've got two ElectroAir Electronic Ignition Systems in my RV-6A. While
>they operate fine once the engine has been started, I'm having a problem
>starting the engine. The ignition systems seem to be in and out of a reset
>mode during the time the starter is running.
> My electrical system has two batteries. One battery is used exclusively
>to power the ignitions during engine start. Both ignitions are enabled
>during the time the starter is ON.
> I've looked at the voltage supplies to both ignitions (with a sampling
>oscilloscope) during the time the starter is running. I've also looked at
>the timing sensor signal. Both traces showed no noise or abnormalities.
>Hence the confusion.....
> My question to the list is, has anyone else had this type of problem (with
>dual electronic ignitions), and more specifically, with ElectroAir
>Ignitions?
If the input voltage is isolated from the starter system
then perhaps the problem is due to some other noise source.
Ground loop in trigger detectors? it would take some experiments
to chase this out. Are you using the single point ground system
recommended in the 'Connection. Do I presume correctly that you've
talked with Jeff Rose and he had no suggestions?
> I'm about to give up on the dual Electronic ignitions, and put an impulse
>Mag in just so the engine starts reliably.... I have ordered two "P" Mags.
>Will I have the same problems with these??????
It's a whole new product specifically designed for aviation
and very unlikely to suffer similar problems. Being a new product
they might have their own, new, growing pains type problems but
I would expect them to be diagnosed and corrected with dispatch.
Bob . . .
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