Today's Message Index:
----------------------
1. 02:07 AM - Re: Jabiru EI pick up (Rob Turk)
2. 07:09 AM - Battery Capacity Check (Tinne maha)
3. 07:13 AM - Re: SPDT momentary push-button switch (comm flip-flop) (Robert L. Nuckolls, III)
4. 07:43 AM - Re: Jabiru EI pick up (Robert L. Nuckolls, III)
5. 07:51 AM - Re: SPDT momentary push-button switch (comm flip-flop) (William Gill)
6. 08:18 AM - connector for sl-30 ()
7. 08:48 AM - Re: SPDT momentary push-button switch (comm flip-flop) (Ron Quillin)
8. 09:03 AM - Re:Dual Voltage Operation of Ford-style Alternator (James Foerster)
9. 09:29 AM - Re: Zanon XRX antenna position (hansriet)
10. 10:01 AM - Re: connector for sl-30 (Ron Raby)
11. 10:33 AM - Re: Re: Zanon XRX antenna position (rtitsworth)
12. 10:33 AM - Re: SPDT momentary push-button switch (comm flip-flop) (William Gill)
13. 12:10 PM - Hitachi Alternator (Joe Dubner)
14. 01:32 PM - Re: Hitachi Alternator (Matt Prather)
15. 02:12 PM - Re: Jabiru EI pick up (Peter Harris)
16. 04:51 PM - Connectors Website (r falstad)
17. 07:28 PM - Zaon MRX antenna position (Ken)
18. 08:11 PM - Re: Broken Battery (Robert L. Nuckolls, III)
19. 08:22 PM - Re: Broken Battery (Robert L. Nuckolls, III)
20. 08:37 PM - Re: Dual Voltage Operation of Ford-style Alternator (Robert L. Nuckolls, III)
21. 08:59 PM - Re: SPDT momentary push-button switch (comm flip-flop) (Robert L. Nuckolls, III)
22. 09:10 PM - Re: SPDT momentary push-button switch (comm flip-flop) (Robert L. Nuckolls, III)
23. 09:23 PM - Re: Battery Capacity Check (Robert L. Nuckolls, III)
24. 09:32 PM - Re: Hitachi Alternator (Joe Dubner)
25. 09:48 PM - Re: Broken Battery THANKS (raymondj)
26. 10:38 PM - Connector for sl-30 (DEAN PSIROPOULOS)
27. 11:42 PM - Re: Dual Voltage Operation of Ford-style Alternator (paulmillner)
28. 11:48 PM - Re: Dual Voltage Operation of Ford-style Alternator (paulmillner)
Message 1
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| Subject: | Re: Jabiru EI pick up |
Peter,
It sounds like you made your pick up too sensitive. Maybe it fires
because other parts of the flywheel are lightly magnetized and cause
early peaks. When you induce current in a coil, the signal will always
show some oscillations. This is the hard part, getting it 'just right'.
you probably do want to get an oscilloscope to watch the signal shape,
so you can see what unwanted peaks exist, and maybe engineer a dampening
circuit that gets rid of them. Nobody said it would be easy...
Rob
----- Original Message -----
From: Peter Harris
To: aeroelectric-list@matronics.com
Sent: Thursday, May 10, 2007 8:06 AM
Subject: AeroElectric-List: Jabiru EI pick up
Hi again,
I have been experimenting with an inductive pick up mounted in place
of one of the magneto coils on the Jab 3300 and can produce a big fat
spark at hand propping speed using a simple electronic ignition module
and an automotive coil feeding the Jab distributor. (I suspect the
original Jab magnetos were intended to drive just one plug not six
through a distributor.) I have been able to increase plug gap to 1.0mm
and cold starting is solved plus better spark through the power range.
The signal from this sensor is about 4 VAC at idle.
But at the higher power settings there is a problem caused by the pick
up sometimes firing in advance maybe from the leading edge of the three
fly wheel magnets. These magnets are also each divided into 3 segments
with an 1/8" air gap between them. The end result is spurious unwanted
firing. (Only the advanced firing can be detected in flight but it may
be firing off the air gaps as well.) Of course the flywheel magnets are
meant to excite a magneto not an inductive sensor, but if it can be made
to work it is a very simple and effective improvement to ignition.
I have run the system using the original magneto primary as a signal
source for the ignition module but the advantage of a big spark with
small movements is lost. (The magneto primary has a transistor which
will fire only when primary voltage reaches a set limit at about 270
rpm.)
It can be solved by increasing the gap clearance to as much as 12mm
but then the advantage of hand propping is lost. Although cold starting
is still fine I am wondering if the power spark is as good as it could
be at this gap setting..
At this stage I have removed the magnet from the inductive pick up and
fitted a steel shield across the span of the magnets at the installation
and still getting a very strong signal but still have the unwanted
firing. I have no access to an oscilloscope.
Next experiment will be with the use of diodes in the signal leads.
But does anyone have a suggestion how to solve this ? I will want to
use the pickup for the EFI conversion later.
Thanks
Peter
Message 2
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| Subject: | Battery Capacity Check |
Bob et al,
I have about 50 hours now on my Lyc O-235 powered ship with Z-11
Architecture (were it not for your help, the airplane would not be flying!)
As my electrical needs are very light, my only alternator is a vacuum pump
pad driven 20 amp.
Recently, while on an extended day VFR trip, I did a load shed/capacity
check as suggested below. Felt good to know real condition results.
However, when I turned the alternator back on for re-charge, the CHT went
way into the red and, after about 20 minutes of charging, the 30 amp fuse
protecting the AWG 10 'B' lead blew, incapacitating the alternator. The
rest of the flight was uneventful, and, after replacing the fuse, everything
functions normally.
One source suggested I replace the 30 amp fuse with a 40 amp one & only due
capacity checks on the ground. Do you have any suggestions, comments or
recommendations?
Grant
Bob,
>
>Where can I get info on how to do a Cap-Check? What equipment is
>required?
>
>I realize this is pretty basic stuff, but I am clueless.
>
>Charlie Brame
>RV-6A N11CB
>San Antonio
The simplest way is to take the time on some long VFR
day flight to put your system into the endurance mode
(turn alternator off and load shed) and see how long
it takes for your battery to get down to 10.5 volts.
This measures the time your battery is capable of
supporting the ship's most useful endurance systems.
Turn the alternator back on and it should recharge the
battery to mostly full in the next 30 minutes or so.
The preferred way is to use test equipment like:
http://westmountainradio.com/CBA_ham.htm
or
http://www.aeroelectric.com/articles/battest.pdf
or install our soon to be released in-situ battery
cap checker.
The point is that while everyone would like to
BELIEVE that their battery is sitting there ready
willing and able to get them comfortably on the ground,
the vast majority of batteries flying as you read
these words would probably fall short of the pilot's
fondest wishes should the alternator crap.
Goto the archives search engine at:
http://www.matronics.com/archives/
Select AeroElectric and then search for
"duration of fuel"
There a rich history of discussion on the value in
KNOWING what your battery is capable of before
you launch.
Bob . . .
_________________________________________________________________
Catch suspicious messages before you open themwith Windows Live Hotmail.
Message 3
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| Subject: | Re: SPDT momentary push-button switch (comm flip-flop) |
At 09:34 PM 5/9/2007 -0500, you wrote:
>I plan to install a comm flip-flop pushbutton switch in a wood grip from
>Custom Aircraft Grips in Kelso, WA. I have a King KX 155 nav/comm which
>requires a SPDT momentary switch for this feature vs. the SPST switch that
>was supplied with the grip. The bore diameter in the grip for the switch
>is 11/32 . I appreciate any leads that are provided regarding a source for
>this switch. Thanks.
>
>
Are there actually three wires that are connected to
this switch? It's unusual to need more than a momentary
connection (usually ground) to a single flip-flop signal
lead. While there might be SPDT ON-(ON) switches described/
recommended for this application, I would be surprised that
a SPST OFF-(ON) switch would not be adequate to the task.
Bob . . .
----------------------------------------
( IF one aspires to be "world class", )
( what ever you do must be exercised )
( EVERY day . . . )
( R. L. Nuckolls III )
----------------------------------------
Message 4
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| Subject: | Re: Jabiru EI pick up |
At 11:02 AM 5/10/2007 +0200, you wrote:
>"urn:schemas-microsoft-com:office:office" xmlns:w =
>"urn:schemas-microsoft-com:office:word">
>Peter,
>
>It sounds like you made your pick up too sensitive. Maybe it fires because
>other parts of the flywheel are lightly magnetized and cause early peaks.
>When you induce current in a coil, the signal will always show some
>oscillations. This is the hard part, getting it 'just right'. you probably
>do want to get an oscilloscope to watch the signal shape, so you can see
>what unwanted peaks exist, and maybe engineer a dampening circuit that
>gets rid of them. Nobody said it would be easy...
>
>Rob
>----- Original Message -----
>From: <mailto:peterjfharris@bigpond.com>Peter Harris
>To: <mailto:aeroelectric-list@matronics.com>aeroelectric-list@matronics.com
>Sent: Thursday, May 10, 2007 8:06 AM
>Subject: AeroElectric-List: Jabiru EI pick up
>
>Hi again,
>I have been experimenting with an inductive pick up mounted in place of
>one of the magneto coils on the Jab 3300 and can produce a big fat spark
>at hand propping speed using a simple electronic ignition module and an
>automotive coil feeding the Jab distributor. (I suspect the original Jab
>magnetos were intended to drive just one plug not six through a
>distributor.) I have been able to increase plug gap to 1.0mm and cold
>starting is solved plus better spark through the power range. The signal
>from this sensor is about 4 VAC at idle.
<snip>
The voltage from an inductor in the presence of a changing magnetic
field is a function of turns in the coil and rate of change of the magnetic
field impressed upon the coil. The phenomenon you describe is predictable.
For example, at low rpm let's say you get a peak voltage pulse of 4 volts.
The voltage begins to rise as the magnetic field fringes first intersect
the coil. As RPM increases, the size of the pulse peak will rise. Let's say
at cruise RPM you're getting 15 volts. Now, if your trigger level for
firing the ignition is something like 2 volts, then you get a spark at 50%
of peak at low rpm and 12% of peak at high rpm. The increase in peak
voltage has the effect of causing the system to trigger earlier at higher
rpm. Rotax touts this as a feature for automatic advancement of spark at
higher rpm. The effectiveness of this advance is debatable . . . advance is
useful but I doubt that the amount of advance achieved by exploiting this
phenomenon is optimal in terms of engine performance.
Without seeing your circuitry and possibly some 'scope pictures of the
trigger waveform, we'd be shooting in the dark if I were to attempt a
change to what you're doing. The problem you're experiencing is not
uncommon. There are signal conditioning chips specifically crafted for
filtering these signals. See: http://cache.national.com/ds/LM/LM1815.pdf
You need to acquire some tools and a 'scope is very high on the list.
I've bought dozens of perfectly useful 'scopes for $200 or less off
Ebay. Look for Tektronix 2200 series 'scopes. I picked up a really clean
2215 a few months ago for $90 plus $25 shipping. Don't worry about probes.
You get nice new ones for about $30 each from dozens of suppliers.
Bob . . .
Message 5
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| Subject: | SPDT momentary push-button switch (comm flip-flop) |
Bob,
SPDT is correct per the installation manual (previously sent to you a
few months ago). If I had known earlier, I wouldn't have made this
provision when I ordered the grip.
I did touching the wire to ground and the frequency toggled ONCE. It was
necessary to then touch this wire to aircraft power to get it to toggle
a second time.
Bill
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Robert L. Nuckolls, III
Sent: Thursday, May 10, 2007 10:13 AM
Subject: Re: AeroElectric-List: SPDT momentary push-button switch (comm
flip-flop)
<nuckollsr@cox.net>
At 09:34 PM 5/9/2007 -0500, you wrote:
>I plan to install a comm flip-flop pushbutton switch in a wood grip
from
>Custom Aircraft Grips in Kelso, WA. I have a King KX 155 nav/comm which
>requires a SPDT momentary switch for this feature vs. the SPST switch
that
>was supplied with the grip. The bore diameter in the grip for the
switch
>is 11/32 . I appreciate any leads that are provided regarding a source
for
>this switch. Thanks.
>
>
Are there actually three wires that are connected to
this switch? It's unusual to need more than a momentary
connection (usually ground) to a single flip-flop signal
lead. While there might be SPDT ON-(ON) switches described/
recommended for this application, I would be surprised that
a SPST OFF-(ON) switch would not be adequate to the task.
Bob . . .
----------------------------------------
( IF one aspires to be "world class", )
( what ever you do must be exercised )
( EVERY day . . . )
( R. L. Nuckolls III )
----------------------------------------
Message 6
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| Subject: | connector for sl-30 |
5/10/2007
Hello Ron, Try Delta RF. See the bottom center of this web page/
http://www.deltarf.com/prodspecial.html
I believe it is part number 4205018N995 copied off the connector on my
SL-30.
Good luck and please tell me why you want it - thanks.
OC -- The best investment we can make is the effort to gather and understand
knowledge.
------------------------------
Time: 11:22:57 AM PST US
From: "Ron Raby" <ronr@advanceddesign.com>
Subject: AeroElectric-List: connector for sl-30
To everyone:
I am looking to get a coax connector for an SL - 30. It is Garmin part #
162 -1008 right angle coax connector. Anyone know what connector this
is?
The dealer wanted to sell me a whole install kit.
Thanks
Ron Raby
Lancair ES
Message 7
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| Subject: | SPDT momentary push-button switch (comm flip-flop) |
At 07:50 5/10/2007, you wrote:
>I did touching the wire to ground and the frequency toggled ONCE. It was
>necessary to then touch this wire to aircraft power to get it to toggle
>a second time.
>
>Bill
I don't have the 155 service/installation manual, but looking at the
SM for the 155A there are some internal pull-up provisions for the
external switch.
A momentary to ground should be all that is required.
By means of whatever type switch you choose to use.
Perhaps there is some issue within your 155?
Ron Q.
Message 8
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| Subject: | Re:Dual Voltage Operation of Ford-style Alternator |
Hello Paul,
Your idea sounds good, and something similar is being done by Lancair
(or the commercial variant, Columbia) with their electrically heated
de-ice system. They run an alternator at very high voltage. I forget
the exact number, but it may by 48 volts.
If you cooling unit will take 48 volts, why not use it? Hard to believe
that you will get too much cooling. Since you will not have a battery
on line for either 28 or higher voltage use, the choice of regulator
will need some care, but I suspect your cooling unit will be less
sensitive to over voltage than most avionics systems. Make sure that
your high voltage regulator can be fed by a diode from the 12v battery
just to get started, and the diode will prevent back feed into the
battery.
I recall in the 1960's when alternators came out, that the back of
Popular Mechanics would advertise plans for using your car alternator as
a welding supply, putting in a connection to the alternator that would
cut out the regulator and let the voltage soar. I never tried it...
Jim Foerster, J400, wiring....
Message 9
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| Subject: | Re: Zanon XRX antenna position |
I own the MRX as well and agree that it's essential for safe flight in high traffic
areas.
I am building the MRX into the panel with the Zaon installation kit (couldn't be
bothered bending the aluminum myself for the $30 they're asking).
The external antenna can be any transponder antenna like the $12 TED antennas that
are for sale on eBay. Don't install the PCAS antenna too close to the transponder
antenna, otherwise you'll need an expensive attenuator.
I don't know if the XRX has the capabilities for external antennas, but that would
be the way to go.
Hans van Riet
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=112041#112041
Message 10
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| Subject: | Re: connector for sl-30 |
Bob
I am trying a new nav antenna and want to build the cable on the bench.
Thanks
Ron Raby
----- Original Message -----
From: <bakerocb@cox.net>
Sent: Thursday, May 10, 2007 10:13 AM
Subject: AeroElectric-List: connector for sl-30
>
> 5/10/2007
>
> Hello Ron, Try Delta RF. See the bottom center of this web page/
>
> http://www.deltarf.com/prodspecial.html
>
> I believe it is part number 4205018N995 copied off the connector on my
> SL-30.
>
> Good luck and please tell me why you want it - thanks.
>
> OC -- The best investment we can make is the effort to gather and
> understand knowledge.
>
> ------------------------------
>
> Time: 11:22:57 AM PST US
> From: "Ron Raby" <ronr@advanceddesign.com>
> Subject: AeroElectric-List: connector for sl-30
>
> To everyone:
>
> I am looking to get a coax connector for an SL - 30. It is Garmin part #
> 162 -1008 right angle coax connector. Anyone know what connector this
> is?
> The dealer wanted to sell me a whole install kit.
>
> Thanks
>
> Ron Raby
>
> Lancair ES
>
>
>
Message 11
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| Subject: | Re: Zanon XRX antenna position |
The XRX antenna is much larger (diameter) as it is a special directional
antenna. A remote option is supposedly in the works from Vaon, but the
prototype @ SNF looked pretty ugly. There are no (visible) remote antenna
ports on a XRX.
Rick
Flying with an XRX interfaced to the 496.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of hansriet
Sent: Thursday, May 10, 2007 12:28 PM
Subject: AeroElectric-List: Re: Zanon XRX antenna position
I own the MRX as well and agree that it's essential for safe flight in high
traffic areas.
I am building the MRX into the panel with the Zaon installation kit
(couldn't be bothered bending the aluminum myself for the $30 they're
asking).
The external antenna can be any transponder antenna like the $12 TED
antennas that are for sale on eBay. Don't install the PCAS antenna too close
to the transponder antenna, otherwise you'll need an expensive attenuator.
I don't know if the XRX has the capabilities for external antennas, but that
would be the way to go.
Hans van Riet
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=112041#112041
Message 12
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| Subject: | SPDT momentary push-button switch (comm flip-flop) |
Ron,
The 155 is fine...the install manual calls for a SPDT switch with
connections to ground AND aircraft power.
Bill
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Ron
Quillin
Sent: Thursday, May 10, 2007 10:44 AM
Subject: RE: AeroElectric-List: SPDT momentary push-button switch (comm
flip-flop)
<rjquillin@gmail.com>
At 07:50 5/10/2007, you wrote:
>I did touch the wire to ground and the frequency toggled ONCE. It was
>necessary to then touch this wire to aircraft power to get it to toggle
>a second time.
>
>Bill
I don't have the 155 service/installation manual, but looking at the
SM for the 155A there are some internal pull-up provisions for the
external switch.
A momentary to ground should be all that is required.
By means of whatever type switch you choose to use.
Perhaps there is some issue within your 155?
Ron Q.
Message 13
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| Subject: | Hitachi Alternator |
My O235 Long-EZ has experienced some sort of charging system failure.
It was intermittent at first but now it does nothing -- I flew home
battery only. So I suspect it's time for brush replacement on my
automotive alternator and I'd like to buy some brushes at the local auto
parts store.
The alternator is an internally regulated Hitachi alternator with no
part number (and I didn't install it). The counter-person at the NAPA
and the AutoZone stores gave me that "deer in the headlight" look when I
asked for brushes for a Hitachi alternator. They only understand car
make, model, and year. So can someone help me with a cross-reference?
The alternator appears to be this one:
http://www.marineengine.com/parts/part_details.php?pnum=SIE18-6284&returntopage240069.htm
(or try this if that wraps around: http://tinyurl.com/2oaokc)
Thanks,
Joe
--------------------------------------------------------------------
Joe Dubner K7JD | 523 Cedar Avenue | http://www.mail2600.com
Long-EZ 821RP | Lewiston, ID 83501 | +1 208 816-6359
--------------------------------------------------------------------
Message 14
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| Subject: | Re: Hitachi Alternator |
Hey Joe,
I'd pull the brush holder out and see if you can identify anything from
that. Maybe take some pics and post them. I found several outfits online
that show brushes for Hitachi alternators. You might also be able to
adapt brushes from a different alternator - they don't seem too tough to
work on.
I might also just call (or head down to) one of the alternator rebuilders
(there might be a local one) and see if they have the brushes.
Huskey Auto Electric in Boise might be able to help you:
(208) 345-2233 - 2301 W Overland RD - Boise, ID 83705
You might also check with Wizard Auto Electric...
(509) 758-6468 - 512 Sycamore St - Clarkston , WA 99403
Regards,
Matt-
>
> My O235 Long-EZ has experienced some sort of charging system failure.
> It was intermittent at first but now it does nothing -- I flew home
> battery only. So I suspect it's time for brush replacement on my
> automotive alternator and I'd like to buy some brushes at the local auto
> parts store.
>
> The alternator is an internally regulated Hitachi alternator with no
> part number (and I didn't install it). The counter-person at the NAPA
> and the AutoZone stores gave me that "deer in the headlight" look when I
> asked for brushes for a Hitachi alternator. They only understand car
> make, model, and year. So can someone help me with a cross-reference?
>
> The alternator appears to be this one:
> http://www.marineengine.com/parts/part_details.php?pnum=SIE18-6284&returntopage240069.htm
> (or try this if that wraps around: http://tinyurl.com/2oaokc)
>
> Thanks,
> Joe
>
> --------------------------------------------------------------------
> Joe Dubner K7JD | 523 Cedar Avenue | http://www.mail2600.com
> Long-EZ 821RP | Lewiston, ID 83501 | +1 208 816-6359
> --------------------------------------------------------------------
>
>
Message 15
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| Subject: | Jabiru EI pick up |
Thanks Bob, your explanation ties in exactly with what is happening and
thanks for the clues to solve it . I will list again when fixed.
Peter
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Friday, 11 May 2007 1:37 AM
Subject: Re: AeroElectric-List: Jabiru EI pick up
<nuckollsr@cox.net>
At 11:02 AM 5/10/2007 +0200, you wrote:
>"urn:schemas-microsoft-com:office:office" xmlns:w =
>"urn:schemas-microsoft-com:office:word">
>Peter,
>
>It sounds like you made your pick up too sensitive. Maybe it fires because
>other parts of the flywheel are lightly magnetized and cause early peaks.
>When you induce current in a coil, the signal will always show some
>oscillations. This is the hard part, getting it 'just right'. you probably
>do want to get an oscilloscope to watch the signal shape, so you can see
>what unwanted peaks exist, and maybe engineer a dampening circuit that
>gets rid of them. Nobody said it would be easy...
>
>Rob
>----- Original Message -----
>From: <mailto:peterjfharris@bigpond.com>Peter Harris
>To: <mailto:aeroelectric-list@matronics.com>aeroelectric-list@matronics.com
>Sent: Thursday, May 10, 2007 8:06 AM
>Subject: AeroElectric-List: Jabiru EI pick up
>
>Hi again,
>I have been experimenting with an inductive pick up mounted in place of
>one of the magneto coils on the Jab 3300 and can produce a big fat spark
>at hand propping speed using a simple electronic ignition module and an
>automotive coil feeding the Jab distributor. (I suspect the original Jab
>magnetos were intended to drive just one plug not six through a
>distributor.) I have been able to increase plug gap to 1.0mm and cold
>starting is solved plus better spark through the power range. The signal
>from this sensor is about 4 VAC at idle.
<snip>
The voltage from an inductor in the presence of a changing magnetic
field is a function of turns in the coil and rate of change of the magnetic
field impressed upon the coil. The phenomenon you describe is predictable.
For example, at low rpm let's say you get a peak voltage pulse of 4 volts.
The voltage begins to rise as the magnetic field fringes first intersect
the coil. As RPM increases, the size of the pulse peak will rise. Let's say
at cruise RPM you're getting 15 volts. Now, if your trigger level for
firing the ignition is something like 2 volts, then you get a spark at 50%
of peak at low rpm and 12% of peak at high rpm. The increase in peak
voltage has the effect of causing the system to trigger earlier at higher
rpm. Rotax touts this as a feature for automatic advancement of spark at
higher rpm. The effectiveness of this advance is debatable . . . advance is
useful but I doubt that the amount of advance achieved by exploiting this
phenomenon is optimal in terms of engine performance.
Without seeing your circuitry and possibly some 'scope pictures of the
trigger waveform, we'd be shooting in the dark if I were to attempt a
change to what you're doing. The problem you're experiencing is not
uncommon. There are signal conditioning chips specifically crafted for
filtering these signals. See: http://cache.national.com/ds/LM/LM1815.pdf
You need to acquire some tools and a 'scope is very high on the list.
I've bought dozens of perfectly useful 'scopes for $200 or less off
Ebay. Look for Tektronix 2200 series 'scopes. I picked up a really clean
2215 a few months ago for $90 plus $25 shipping. Don't worry about probes.
You get nice new ones for about $30 each from dozens of suppliers.
Bob . . .
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| Subject: | Connectors Website |
For what it's worth, while searching the web for pin out diagrams for
D-Sub connectors, I found the following site that has drawings and
pinouts for virtually every connector you (at least I) can think of.
http://pinouts.ru/<http://pinouts.ru/>
Note it is based in Russia but on my limited viewing, seems to be
accurate.
Best regards,
Bob
Message 17
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| Subject: | Zaon MRX antenna position |
Hans
Are you saying that satisfactory operation has been obtained with an
external antenna but without the $150. coax cable and "gain adapter" ?
I'm surprised that the installation manual insists that a single
external MRX antenna must be on the bottom of the aircraft. Before
seeing that manual I was thinking of trying an external antenna on the
roof. With a high wing VFR airplane I figure my blind spot and most of
my traffic is above me most of the time. I don't think I'm willing to
spend $280. for dual antenna cabling plus the antenna cost since the
unit works fairly well just sitting on my glareshield.
Ken
hansriet wrote:
>
>I own the MRX as well and agree that it's essential for safe flight in high traffic
areas.
>I am building the MRX into the panel with the Zaon installation kit (couldn't
be bothered bending the aluminum myself for the $30 they're asking).
>The external antenna can be any transponder antenna like the $12 TED antennas
that are for sale on eBay. Don't install the PCAS antenna too close to the transponder
antenna, otherwise you'll need an expensive attenuator.
>
>I don't know if the XRX has the capabilities for external antennas, but that would
be the way to go.
>
>Hans van Riet
>
>
Message 18
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At 02:53 PM 5/9/2007 -0500, you wrote:
>
>Bob,
>
> It is my understanding that it takes relatively few (not
> quantified because
>I don't have a quantity) full discharges to diminish the capacity of some
>types of batteries. Is this correct? Do you have any info you can add to
>firm up or discredit this idea.
A battery's service life is dependent on a host of variables
but with all things but deep-discharge cycles held constant,
the number of cycles until useful capacity drops to 80% of
nameplate value is a useful way to compare batteries.
It's also true that a battery's design can be optimized for
repeated deep-cycle service as opposed to say purely "cranking"
service. Take a peek at the Enersys Genesis application manual
at:
http://www.batterystore.com/Yuasa/YuasaPDF/GenesisApManual.pdf
and particular Figure 2.3.1 at:
http://www.aeroelectric.com/Pictures/Curves/Genesis_Cycle_Life.jpg
Here's a battery that under laboratory conditions is rated
for deep cycles (down to 10% or less of capacity) in excess
of 300 cycles.
At the same time, I've seen some claims by various authors
that some models of "deep cycle" battery can be depended upon for
perhaps 18-20 deep discharges while "cranking" versions tossed
in the towel at 3-4.
> Does doing cap checks present any risk to the battery?
Sure, a true capacity test requires that the battery be
deep cycled in so that one can count all the electrons it
contains. Obviously, one doesn't want to do a cap check at
the end of every flight, no matter how convenient. In practical
terms, one could wait a year for the first cap check assuming
the battery had not be discharged and allowed to sit for
a long time. In this case, I'd do a cap check right after
the first charge to recover it. It it looks okay, run it
a month or so before doing another cap check. If still
okay, revert to original schedule of 1 year and every
6 months thereafter. But if the capacity is marginal after
the first recover charge and doesn't go up a bit in capacity
for the second test, then this battery is probably "damaged
goods" and is worthy of peeking at it more often.
I've oft likened batteries to persnickety house plants.
If treated to optimize its life (assuming one knows exactly
what that means) then you can expect performance equal to
the designers goals. But most of us do not wish to become
Master Gardeners any more than we want to become Master
Battery Tenders. It's that old cost-of-ownership thing.
My own philosophy would be to buy inexpensively, and if
convenient, test occasionally but be ready to throw a new
puppy into the harness at the slightest question that my
endurance goals would not be met if I ran it another
test cycle (6 months or what ever you're using).
If your head is getting tight over optimizing your
battery purchase and maintenance decisions, then I'll
suggest that it's not your goal to become a Master Battery
Tender either. This is what prompts us to consider the
companion accessory to the IR Alternator Controller . . .
the In-Situ Battery Capacity Tester. This device will
offer an exceedingly convenient means by which one may
accomplish a meaningful test of the battery without
removing it from the airplane. At the same time, it
relieves us from resorting to purchases of premium
batteries with the mistaken notion that just because
it costs a lot more, we don't have to "worry" about it
so much.
A bit of battery maintenance knowledge and low cost
tools go a long way toward replacing worries with a
confident expectation supported by repeatable
experiment.
Bob . . .
Message 19
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>
> The simplest way is to take the time on some long VFR
> day flight to put your system into the endurance mode
> (turn alternator off and load shed) and see how long
> it takes for your battery to get down to 10.5 volts.
> This measures the time your battery is capable of
> supporting the ship's most useful endurance systems.
>
>
>Bob,
>
>If one is going to do what you say above, I would make sure that the
>avionics switch is off and the engine is at low rpms when you turn the
>alternator back on. I forgot to turn the alternator on one time, and
>suddenly my radios went silent. I noticed that the alternator switch was
>off, so I turned it back on. I zapped a Garmin 430 that way. Fortunately,
>it was still in warranty, and they fixed it, but it surely was embarrassing
>as well as potentially dangerous. I hope it never happens again, but if it
>does, I will think twice about turning on the alternator while the prop is
>swinging cruise rpms and the avionics switch is turned on.
>
>Simon Ramirez, passing through Odessa, TX
Point well taken. If the ship's battery is poorly and/or
the alternator-regulator is prone to severe overshoot during
a turn-on event, the situation you describe is a risk.
However, it would have been really interesting to
repeat your experiment (radios off of course) and get data
on the magnitude and duration of the overshoot. Recall that
DO-160 calls for a 20V, 1-second withstand. See:
http://www.aeroelectric.com/articles/Whats_all_this_DO160_Stuff_Anyhow.pdf
I would be exceedingly surprised if your system pushed outside
this boundary. This suggests that while you probably DID
experience an overshoot event, it may have been the overshoot
combined with a edge of tolerance for the radio. Do you
have the manual for the 430? What does it say about DO-160
power input qualification?
But to be really gentle on things, the in-flight capacity
test should be terminated by first reducing the engine to flight-
idle before turning the alternator back on. If your battery just
passed the cap check, then it's also well capable of doing
it's job as the great mitigator of transient events. If the
thing died way earlier than you expected, then not only do you
want to consider a new battery at your earliest convenience,
exercising caution for bringing the system back up is certainly
warranted. Thanks for reminding me!
Bob . . .
----------------------------------------
( IF one aspires to be "world class", )
( what ever you do must be exercised )
( EVERY day . . . )
( R. L. Nuckolls III )
----------------------------------------
Message 20
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| Subject: | Re: Dual Voltage Operation of Ford-style Alternator |
At 03:15 PM 5/9/2007 -0700, you wrote:
><paulmillner@COMPUSERVE.COM>
>
>Hi Bob,
>
>I'm considering a slightly unusual configuration on a Lycoming IO360A
>installation... 12 volt alternator on a vacuum pad on the back of the
>engine... powers the "essential" bus (there's a word you prefer to
>essential, but it's late and I can't recall... well, I'm in Holland, too,
>standing up in an internet cafe, and the wind is howling... enough excuses)
>
>The "standard" Ford-style alternator on the front will attach to the
>airconditioning (HVAC) bus... in the back of the plane, a variable voltage
>air conditioining unit (Kelly Aerospace Thermawing or similar) will be
>powered by the HVAC bus.
>
>Under normal, non-cooling operation, the HVAC bus will be connected to
>the main bus. The regulator will recognize this fact and regulate for
>nominal 14 VDC. Both alternators will power the 14 volt systems.
>
>When cooling is wanted (and of course loads allow for the rear mounted
>alternator to carry the requirements), the breaker or contactor will be
>opened between the HVAC bus and the main bus. This will also enable the
>regulabor to assume 28 VDC mode.
>
>The air conditioning unit will put out some cool air at 14 volts, but
>twice as much cool air at 28 volts. The unit draws 50 amps over a voltage
>range of 12 volts to 48 volts, and cooling output varies proportionately.
>
>Any fatal flaw to this plan?
>
>Assuming I use a 28 volt alternator (assume for the moment the
>Cessna-style Ford Aeromotive once), should it regulate "happily" at 14
>volts? I can think of schemes to "fool" the regulator with a voltage
>divider connected to the A lead... switched as required to make a 14 volt
>regulator think that 28 volts meets its needs, I'm sure you have the picture.
>
>Thoughts? I've already tried to talk the better half out of retiring to a
>hot place... and am now preparing contingency plans to deal with the
>eventuality! :-)
>
>Paul, Berkeley CA (soon to be Palm Springs CA)
Is this the same Paul Millner with whom I shared many an
intriguing conversation back in the Compuserve AVSIG days?
What you propose has merit. I think I'd go for a more
controlled approach. Wire per Z-14 but with the main bus
split into a 14v ops and 28V HVAC busses. When in 14V ops
mode, both busses are tied together and the alternator
is controlled by a 14V regulator. When the higher performance
HVAC ops are desired, split the busses and control the
alternator with a B&C SR-1 regulator which is specifically
designed to operate a 14V alternator in 28V system. Under
this mode, goodies on the 14v portion of the main bus would
be allowed to go dark but could be brought up quickly by
closing the crossfeed contactor to the opposite side which
is always up and running at 14v.
Maybe we need an new Z-figure . . . perhaps a Z-14PM?
Bob . . .
Message 21
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| Subject: | SPDT momentary push-button switch (comm flip-flop) |
At 09:50 AM 5/10/2007 -0500, you wrote:
>
>Bob,
>
>SPDT is correct per the installation manual (previously sent to you a
>few months ago). If I had known earlier, I wouldn't have made this
>provision when I ordered the grip.
Oh yeah, thanks for reminding me.
>I did touching the wire to ground and the frequency toggled ONCE. It was
>necessary to then touch this wire to aircraft power to get it to toggle
>a second time.
Okay, take a peek at:
http://www.aeroelectric.com/Pictures/Schematics/KX-155_Flip-Flop_Alternative.jpg
I think you can fool the radio into believing that there's a
SPDT on-(on) switch in your stick grip. Wire the SPST n.o. push
button as shown in the lower half of the drawing. This switch will
apply the expected 14v when the button is pushed just as required
in the upper half of the drawing. When the switch is open, the
resistor pulls the line to ground with probably enough Umph to
make the radio believe that its a real, double-throw switch.
See if this works and get back to us.
Bob . . .
Message 22
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| Subject: | SPDT momentary push-button switch (comm flip-flop) |
At 08:44 AM 5/10/2007 -0700, you wrote:
>
>At 07:50 5/10/2007, you wrote:
>>I did touching the wire to ground and the frequency toggled ONCE. It was
>>necessary to then touch this wire to aircraft power to get it to toggle
>>a second time.
>>
>>Bill
>
>I don't have the 155 service/installation manual, but looking at the SM
>for the 155A there are some internal pull-up provisions for the external
>switch.
>A momentary to ground should be all that is required.
>By means of whatever type switch you choose to use.
>
>Perhaps there is some issue within your 155?
Aha! good data sir. How big are the resistors and to
what voltage do they pull up? The snipit from the
install manual suggests that pulling to ground is
the expected resting condition with the lead being
pulled up to +14 to effect a "flip".
If the radio has internal pull-ups, then a NORMALLY
CLOSED push button would be expected to provide the
necessary function but without a need for external
resistor. A Grayhill 30-6 illustrated at:
http://embrace.grayhill.com/embrace/IMAGES/PDF/E-17-20.pdf
and available from digikey at:
http://tinyurl.com/2nqymz
for about $2.65 should do the job.
Looks like you have a little bit of homework to do
Bill but I'm 90% certain that you can make a single-throw,
two-wire push button do this job.
I'm going to take the sketch referenced in the
earlier post down from the website. Given Ron's
new information, I'm not sure we want the signal
lead to "rest" in the low state.
Bob . . .
Message 23
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| Subject: | Re: Battery Capacity Check |
At 07:07 AM 5/10/2007 -0700, you wrote:
>
>Bob et al,
>
>I have about 50 hours now on my Lyc O-235 powered ship with Z-11
>Architecture (were it not for your help, the airplane would not be flying!)
>As my electrical needs are very light, my only alternator is a vacuum pump
>pad driven 20 amp.
>Recently, while on an extended day VFR trip, I did a load shed/capacity
>check as suggested below. Felt good to know real condition results.
>However, when I turned the alternator back on for re-charge, the CHT went
>way into the red and, after about 20 minutes of charging, the 30 amp fuse
>protecting the AWG 10 'B' lead blew, incapacitating the alternator. The
>rest of the flight was uneventful, and, after replacing the fuse,
>everything functions normally.
>One source suggested I replace the 30 amp fuse with a 40 amp one & only
>due capacity checks on the ground. Do you have any suggestions, comments
>or recommendations?
Without a doubt, recharging the battery with a cruise
RPM alternator produces a max-effort recharge event . . .
which shouldn't be a big deal but the practice will
produce a short term (15 minutes or so) exercise of
the alternator. What size alternator do you have? Recall
that the b-lead fuse needs to be 20% or so LARGER than
the alternator's rated output to accommodate exactly
this same scenario . . . Had a Cherokee 140 nuisance
trip the 60A b-lead breaker at the outset of a trip
some years ago after we jump started the airplane
due to master switch being left on.
Obviously, the least stressful way to do it is
on the ground with test equipment. But at the same
time, the in-flight test is a proving ground for
whether or not all the design goals have been met.
You've discovered that your b-lead fuse is too small.
Bob . . .
Message 24
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| Subject: | Re: Hitachi Alternator |
Thanks, Matt. Heading down to Wizard Electric in Clarkston is "plan B"
but I'm hoping someone on the list who works in the automotive
electrical business can tell me the make and model of the car my
alternator comes from.
This points out a real problem with a homebuilt that uses automotive
parts. When it changes hands somewhere down the line, the new owner may
be in for a tough time when the starter/alternator/whatever goes out
unless it's well documented.
Best Regards,
Joe
--------------------------------------------------------------------
Joe Dubner K7JD | 523 Cedar Avenue | http://www.mail2600.com
Long-EZ 821RP | Lewiston, ID 83501 | +1 208 816-6359
--------------------------------------------------------------------
On 10-May-07 13:31 Matt Prather wrote:
>
> Hey Joe,
>
> I'd pull the brush holder out and see if you can identify anything from
> that. Maybe take some pics and post them. I found several outfits online
> that show brushes for Hitachi alternators. You might also be able to
> adapt brushes from a different alternator - they don't seem too tough to
> work on.
>
> I might also just call (or head down to) one of the alternator rebuilders
> (there might be a local one) and see if they have the brushes.
>
> Huskey Auto Electric in Boise might be able to help you:
>
> (208) 345-2233 - 2301 W Overland RD - Boise, ID 83705
>
> You might also check with Wizard Auto Electric...
>
> (509) 758-6468 - 512 Sycamore St - Clarkston , WA 99403
>
>
>
> Regards,
>
> Matt-
>
>>
>> My O235 Long-EZ has experienced some sort of charging system failure.
>> It was intermittent at first but now it does nothing -- I flew home
>> battery only. So I suspect it's time for brush replacement on my
>> automotive alternator and I'd like to buy some brushes at the local auto
>> parts store.
>>
>> The alternator is an internally regulated Hitachi alternator with no
>> part number (and I didn't install it). The counter-person at the NAPA
>> and the AutoZone stores gave me that "deer in the headlight" look when I
>> asked for brushes for a Hitachi alternator. They only understand car
>> make, model, and year. So can someone help me with a cross-reference?
>>
>> The alternator appears to be this one:
>> http://www.marineengine.com/parts/part_details.php?pnum=SIE18-6284&returntopage240069.htm
>> (or try this if that wraps around: http://tinyurl.com/2oaokc)
>>
>> Thanks,
>> Joe
>>
>> --------------------------------------------------------------------
>> Joe Dubner K7JD | 523 Cedar Avenue | http://www.mail2600.com
>> Long-EZ 821RP | Lewiston, ID 83501 | +1 208 816-6359
>> --------------------------------------------------------------------
>>
>>
>>
>>
>>
>
>
>
>
>
>
>
Message 25
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| Subject: | Broken Battery THANKS |
Bob,
Thanks for the reply.
Raymond Julian
Kettle River, MN
do not archive
>-----Original Message-----
>From: owner-aeroelectric-list-server@matronics.com
>[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert
>L. Nuckolls, III
>Sent: Thursday, May 10, 2007 11:11 PM
>To: aeroelectric-list@matronics.com
>Subject: RE: AeroElectric-List: Broken Battery
>
>
><nuckollsr@cox.net>
>
>At 02:53 PM 5/9/2007 -0500, you wrote:
>
><raymondj@frontiernet.net>
>>
>>Bob,
>>
>> It is my understanding that it takes relatively few (not
>> quantified because
>>I don't have a quantity) full discharges to diminish the capacity of some
>>types of batteries. Is this correct? Do you have any info you can add to
>>firm up or discredit this idea.
>
Message 26
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| Subject: | Connector for sl-30 |
You're in luck Ron, I started installing my radio stack wiring harness this
evening and happen to have the package handy. Keep in mind that I bought my
radios a few years ago before Garmin took over but it should still work for
you if they haven't made any physical changes to the chassis.
The package the connector came in says:
Delta Electronics MFG Corp.
Boston, MA 01915
Part number: 4205 018 N995 01 30
Quality RF Connectors
Telephone 978-927-1060
Both the NAV and COMM connectors are the same for my unit and are the right
angle type you describe with an ear on either side that studs go thru to
hold it to the tray. Hope that helps.
Dean Psiropoulos
RV-6A N197DM
Radio install
__________________________ Original Message _____________________________
From: "Ron Raby" <ronr@advanceddesign.com>
Subject: AeroElectric-List: connector for sl-30
I am looking to get a coax connector for an SL - 30. It is Garmin part #
162 -1008 right angle coax connector. Anyone know what connector this
is?
Message 27
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| Subject: | Re: Dual Voltage Operation of Ford-style Alternator |
Hi Bob!
Indeed, it's the same me. :-) I wasn't aware of that functionality of the SR-1
regulator... do folks operate 14 V alternators in 28 volt systems simply because
14 V alternators are less expensive?
Any other ampacity limits to a 14 volt alternator in that service?
I was curious how far one could push a 14 volt alternator before reliability becomes
an issue... making 48 volts at 50 amps seems like a stretch for a 14 volt
/ 60 amp device... I'm thinking of brush current/arcing, and I squared R heating
of both the rotor and the stator.
The good news is that *usually* the HVAC usage should be transient... but there
are times, especially with an inversion and ATC weirdness, when one would bump
along in warm conditions quite some time... though the output could likely be
reduced, say, to 28 volts.
How do 14 volt alternators hold up in 28 volt systems at, say, 80% rated load?
Paul, remote from Amsterdam
--------
Paul Millner, Berkeley CA [OAK]
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=112189#112189
Message 28
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| Subject: | Re: Dual Voltage Operation of Ford-style Alternator |
Hi Jim, thanks for your comments.
>> something similar is being done by Lancair (or the commercial variant, Columbia)
with their electrically heated de-ice system. They run an alternator at very
high voltage. I forget the exact number, but it may by 48 volts.
That's the same group of folks, Kelly Aerospace Thermowing, that make this HVAC
unit. It's a 135 amp, 70 volt alternator... but of course it's designed for
that service, and costs just under $3,000.
>> If your cooling unit will take 48 volts, why not use it?
I'm concerned about i-squared-r heating of the rotor and stator windings, leading
to insulation breakdown, as well as significant reduction of brush life due
to arcing at the signficantly higher field current/voltage. Don't want to smoke
the alternator regularly!
>> Hard to believe that you will get too much cooling.
That's likely not a concern, true!
>> Since you will not have a battery on line for either 28 or higher voltage use,
the choice of regulator will need some care, but I suspect your cooling unit
will be less sensitive to over voltage than most avionics systems. Make sure
that your high voltage regulator can be fed by a diode from the 12v battery just
to get started, and the diode will prevent back feed into the battery.
Good thought.
>> I recall in the 1960's when alternators came out, that the back of Popular Mechanics
would advertise plans for using your car alternator as a welding supply,
putting in a connection to the alternator that would cut out the regulator
and let the voltage soar. I never tried it...
Well, I don't know about welding, but of course, that would be transient loading,
not hours of operation in that mode... typically. In fact, I installed one
of those adapters on my '72 Ford Galaxie, and operated AC/DC power tools at my
tiedown quite well.
Paul, remote from Amsterdam
--------
Paul Millner, Berkeley CA [OAK]
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