Today's Message Index:
----------------------
1. 05:50 AM - Re: Kind of off topic. Speed sensor needed. (Sam Hoskins)
2. 05:50 AM - Re: Stec 30 Autopilot & GPSS conversion (Greenbacks, UnLtd.)
3. 05:50 AM - Re: Stec 30 Autopilot & GPSS conversion (Greenbacks, UnLtd.)
4. 06:37 AM - I need a larger photo, please (DeWitt Whittington)
5. 07:09 AM - Re: Kind of off topic. Speed sensor needed. (Robert L. Nuckolls, III)
6. 07:20 AM - Re: RV-8 - Instrument Panel Power Coat & Silkscreen... ()
7. 07:56 AM - Re: Warm-up Problem (Deene Ogden)
8. 08:14 AM - Re: Feedback while transmitting (Michael Hilderbrand)
9. 08:44 AM - Re: Kind of off topic. Speed sensor needed. (Robert L. Nuckolls, III)
10. 09:33 AM - Re: I need a larger photo, please (Matt Dralle)
11. 09:33 AM - Re: Kind of off topic. Speed sensor needed. (Sam Hoskins)
12. 09:54 AM - Re: Warm-up Problem (David & Elaine Lamphere)
13. 10:42 AM - Re: Feedback while transmitting (Robert L. Nuckolls, III)
14. 11:44 AM - Re: Feedback while transmitting (ROGER & JEAN CURTIS)
15. 02:28 PM - Re: I need a larger photo, please (Stein Bruch)
16. 02:57 PM - HID bulb types ()
17. 04:25 PM - Re: HID bulb types (XeVision)
18. 06:01 PM - Follow Up to Power Opti-Miser (Dennis Johnson)
19. 07:42 PM - Re: Follow Up to Power Opti-Miser (Robert L. Nuckolls, III)
Message 1
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Subject: | Re: Kind of off topic. Speed sensor needed. |
Bob, I think that 1 millisecond accuracy would be fine. I think, just my
opinion, if we could determine speed to one digit, it would be fine, eg.
234.6 mph. Of course, two digits would be better.
Thanks to all who contributed suggestions. I have complied and posted all
of them to the SARL racers group.
For anyone who may be interested and wish to join, the e-mail list is at:
http://groups.yahoo.com/group/SARL-Racers/
Sam
On Tue, Dec 15, 2009 at 9:54 AM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> nuckolls.bob@aeroelectric.com>
>
>
> On 15 Dec 2009, at 4:46 AM, Robert L. Nuckolls, III wrote:
>
> Yes, photo cells looking straight up though a tube of 2 - 4"
> and length adjusted so that subtended angle of view is sufficiently
> small that the "shadow" of any part of the aircraft blocks the
> skylight. There are some self-calibrating level sensor circuits
> that will adjust for slow variability in sky light levels.
>
> E: This would work well - even if the light sensor wasn't in a tube,
> calibrated correctly, the change from direct sunlight to shadow should be
> enough to trigger a timing device of some description.
>
> You need to constrain the view angle . . .preferably
> without the use of optics. Long tubes seem the simplest
> approach.
>
> E: I would suggest two or three sensors in a line across the runway. Then
> use the second or third sensor that is triggered so that you know it's the
> wing that's causing the shadow both times, and not the wing on the first
> end, and the spinner on the second (which would skew results).
>
> That would be useful . . . depending on how "loose"
> the rules are for alignment with the runway ceneterline,
> an array of senors of any number could be used.
>
> E: Even a very simple microprocessor would be able to do the timing
> accurately enough, and could display the result on an LCD screen without too
> much effort.
>
> Sure, the jellybean PIC products offer one set of
> solutions.
>
> E: There is one downside to this, if you're keen on using either end of a
> runway, I guess you're looking for about 1km between sensors. That's a lot
> of wire to wind up at the end of each competition! There may be some simple
> radio interfaces that could be substituted...?
>
> Ten years ago, I helped some RC racers craft a timing system
> that required communication over a many acres of event
> venue. Off the shelf, 433 MHz transmiter and receiver
> modules provided links. Controlling atency and jitter in
> detecting event-edges would be a critical design goal.
>
> Assuming 300 mph (440 f/s) over 5000 feet of runway
> (11.3 seconds) a .1% accuracy in timing would call for
> control of variability to less than 10 milliseconds.
> If shorter runs are anticipated, the number gets tighter.
> +/-1 millisecond would probably be a practical design goal.
>
> Sam. Define "accurate". What are the design goals for
> the reduction of uncertainty?
>
> Bob . . .
>
>
Message 2
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Subject: | Re: Stec 30 Autopilot & GPSS conversion |
I'd like to make contact with anyone in this group who has recent
experience or knowledge with regard to wiring this autopilot.
I have a couple of questions/issues which may ultimately be of
interest here but please contact me directly for now.
Thanks,
Angier Ames
Lancair 360
N4ZQ
Message 3
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Subject: | Re: Stec 30 Autopilot & GPSS conversion |
I'd like to make contact with anyone in this group who has recent
experience or knowledge with regard to wiring this autopilot.
I have a couple of questions/issues which may ultimately be of
interest here but please contact me directly for now.
Thanks,
Angier Ames
Lancair 360
N4ZQ
Message 4
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Subject: | I need a larger photo, please |
Matt,
Your panel looks super. However, I can only read, maybe, the N
number. Is there a way for you to post a larger photo of your panel
so I can see more in detail how your powder coated panel labels read
and look.
And exactly how were the labels done? We are just about to have our
panel powder coated and labeled. Boy, is it difficult to figure out
the wording for each switch, etc.
Dee
DeWitt (Dee) Whittington
406 N Mulberry St
Richmond, VA 23220-3320
(804) 358-4333 phone and fax
SKYPE: hilltopkid
dee.whittington@gmail.com
Message 5
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Subject: | Re: Kind of off topic. Speed sensor needed. |
At 07:28 AM 12/17/2009, you wrote:
>Bob, I think that 1 millisecond accuracy would be fine. I think,
>just my opinion, if we could determine speed to one digit, it would
>be fine, eg. 234.6 mph. Of course, two digits would be better.
It's technically feasible to get about any resolution
you want but the costs of producing a user-friendly
system can go up really fast as you add those decimal
points!
I did a drag track clocking system design many many
moons ago wherein we used telescopes looking across
the track at a strong light source. Magnification was
so high that the entire illumination disk (6" roundel)
filled the field of view in the telescope eyepiece.
This system was vacuum tube sensor systems driving
an HP counter/timer that was also vacuum tube and
used columns of neon bulbs to display measured
result.
In this instance, ambient light had no measurable
effect on triggering accuracy. It worked equally
well at night or bright sunlight. Further, uncertainty
of trigger timing was limited to the time it took
for the vehicle to cross the 6" field of view. So
back in 1974 or thereabouts, we had 0.1 mS resolution
and 1 mS accuracy of timing over the distance between
sensors. I think they installed them 10' apart at the
end of the track. At 150 f/s, the interval of interest
was about 66 milliseconds so we could calculate speed
with an accuracy of about 1.5% Folks were impressed
by that kind of capability back then.
Photo-detectors looking at sky-light through tubes
(or even cheap telescopes) offers a means by which
uncertainty in trigger timing (dd/dt) can be very small.
But as others pointed out, very small apertures,
require resolution of the differences between a prop
spinner and leading edge of wing. So an array of
sensors driving a discriminator calling for two
or more sensors to be triggered before the hack
is marked seems to offer a solution.
The use of radio to tie the ends of the system together
is quite practical. There are inexpensive, off the shelf
timers available with micro-second resolution/accuracy.
The proof of the pudding is in the sensor array.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 6
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Subject: | RV-8 - Instrument Panel Power Coat & Silkscreen... |
Great job Matt - Don't forget to look out the window while watching
those DVD's :)
I'm going to ditch my aluminum stuff and cut mine out of Carbon Fiber.
That stuff is so strong and easy to work with, I see not use in paying
the painter.
Enjoy.
Glenn E. Long
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Matt
Dralle
Sent: Wednesday, December 16, 2009 10:30 PM
Subject: AeroElectric-List: RV-8 - Instrument Panel Power Coat &
Silkscreen...
Listers,
I got the instrument panel back from power coat and silkscreen today and
I just couldn't wait to stick the instruments in to see what it looks
like!
Sweet!!
I can hardly wait to get it mounted and powered back up!
Matt Dralle
RV-8 #82880 N998RV
http://www.mattsrv8.com - Matt's RV-8 Construction Blog Final Assembly
Message 7
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Subject: | Re: Warm-up Problem |
You should check your alternator to see if the diode bridge is OK. If a
diode fails, then the output from the alt will be very noisy and especially
at higher output levels.
Deene Ogden
RV8
CFII, MEI, CFIG
Message 8
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Subject: | Re: Feedback while transmitting |
Thanks Gus, =0A=0AMy headphone jacks (and headsets) are in close proximity
of the antenna.--The jacks are located on the first former behind the s
eat and the antenna is just above all that on-top of the turtle deck. =0A
=0AI will move things around and see what happens.--=0A-Michael Hilde
rbrand=0ADerby, Kansas=0AHttp://www.kansasflying.com =0A=0A=0A=0A=0A_______
_________________________=0AFrom: Gus Schlegel <airgus@kc.rr.com>=0ATo: aer
oelectric-list@matronics.com=0ASent: Wed, December 16, 2009 8:07:39 PM=0ASu
bject: Re: AeroElectric-List: Feedback while transmitting=0A=0A--> AeroElec
tric-List message posted by: Gus Schlegel <airgus@kc.rr.com>=0A=0AMichael H
ilderbrand wrote:=0A> I am getting a loud feedback noise in my headset when
I press the PTT.- It only seems to happen 70% of the time - having the e
ngine running, or not, is of no difference.- Today in the hangar I presse
d the PTT and could hear the feedback coming out of the speakers of my jam-
box radio several feet away! The radio on the jam-box was on but the volume
turned all the way down. When I unplugged it I could no longer hear the no
ise in the jam-box, but it was VERY present in my headphones. Of course, th
is in a new installation in my airplane - flown the plane 2 times now.- N
ot being able to her yourself talk is frustrating! Oh.. yeah, the receiving
end ALWAYS hears me "loud & clear."- Anyone have a good FIRST place to s
tart looking to fix this problem. It seems- like it might be a simple fix
.... a ground maybe? Inadequate antenna?- Thanks!=0A>- Michael Hilderbr
and=0A> Derby, Kansas=0A> Http://www.kansasflying.com=0A> *=0A> *=0AI had t
he same problem, intermittent feedback - until I started moving my headset
cables around and voila! At a certain position in relation to the antenna c
able it started squealing. I rerouted my antenna cable and the problem went
-=- - - - - - - - - - - - - - - -Matt Drall
=
Message 9
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Subject: | Re: Kind of off topic. Speed sensor needed. |
> The use of radio to tie the ends of the system together
> is quite practical. There are inexpensive, off the shelf
> timers available with micro-second resolution/accuracy.
> The proof of the pudding is in the sensor array.
What is the size of the "box" that the aircraft must stay inside
and what height above the ground is the lower edge of that box?
I occurs to me that if you have a 100' wide by 100' high
box with lower edge at 100' agl, the number of sensors
required to cover that up-look area with any resolution
could be pretty big. Fortunately, they're cheap and easy
to build. So is the electronics for resolving the presence
of an airplane "shadow"
Bob . . .
////
(o o)
===========o00o=(_)=o00o========
< Go ahead, make my day . . . >
< show me where I'm wrong. >
================================
Message 10
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Subject: | Re: I need a larger photo, please |
At 06:34 AM 12/17/2009 Thursday, you wrote:
>
>Matt,
>
>Your panel looks super. However, I can only read, maybe, the N number. Is there
a way for you to post a larger photo of your panel so I can see more in detail
how your powder coated panel labels read and look.
>
>And exactly how were the labels done? We are just about to have our panel powder
coated and labeled. Boy, is it difficult to figure out the wording for each
switch, etc.
>
>Dee
>
>DeWitt (Dee) Whittington
>406 N Mulberry St
>Richmond, VA 23220-3320
>(804) 358-4333 phone and fax
>SKYPE: hilltopkid
>dee.whittington@gmail.com
Here is the full-resolution shot of the panel. I used a textured power coat that
looks really nice. Same as I used on the engine baffles. The silk screen
looks okay. In retrospect, I think that I would have power coated the panel gloss
black, did the silk screen, then had them put a clear texture power coat
over the top.
For the right side control panel, I'm having them use a "label" the full size of
the panel. The stuff looks just like the power coated panel in both texture
and color. The lettering, however is super crisp. I'll post some pictures when
I get it back. I also had them make up some similar labels for the various
remote controls like the Alternate Air and Cabin Heat.
Matt Dralle
RV-8 #82880 N998RV
http://www.mattsrv8.com
Final Assembly
Message 11
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Subject: | Re: Kind of off topic. Speed sensor needed. |
The box would be the width of the runway, with the pilot striving to stay
pretty much on the center line. Probably as low as 20 feet and as high as
100 feet - maybe 75.
On Thu, Dec 17, 2009 at 10:41 AM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> nuckolls.bob@aeroelectric.com>
>
>
> The use of radio to tie the ends of the system together
>> is quite practical. There are inexpensive, off the shelf
>> timers available with micro-second resolution/accuracy.
>> The proof of the pudding is in the sensor array.
>>
>
> What is the size of the "box" that the aircraft must stay inside
> and what height above the ground is the lower edge of that box?
>
> I occurs to me that if you have a 100' wide by 100' high
> box with lower edge at 100' agl, the number of sensors
> required to cover that up-look area with any resolution
> could be pretty big. Fortunately, they're cheap and easy
> to build. So is the electronics for resolving the presence
> of an airplane "shadow"
>
>
> Bob . . .
> ////
> (o o)
> ===========o00o=(_)=o00o========
> < Go ahead, make my day . . . >
> < show me where I'm wrong. >
> ================================
>
>
Message 12
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Subject: | Re: Warm-up Problem |
If that was the case, wouldn't the frequency of the shriek be lower?? -
and continue to be noisy all the time? It ouzzles me that on stops where
I re-fuel and startup again - there's no noise right after startup...
Thanks for your input - I thought I'd get a lot more suggestions from
the group. Everyone must be shopping :-)
Dave (N365DL)
PS. 40.5 hrs today! Phase 1 complete!!!
----- Original Message -----
From: Deene Ogden
To: aeroelectric-list@matronics.com
Sent: Thursday, December 17, 2009 10:54 AM
Subject: Re: AeroElectric-List: Warm-up Problem
You should check your alternator to see if the diode bridge is OK. If
a diode fails, then the output from the alt will be very noisy and
especially at higher output levels.
Deene Ogden
RV8
CFII, MEI, CFIG
Message 13
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Subject: | Re: Feedback while transmitting |
At 10:09 AM 12/17/2009, you wrote:
>Thanks Gus,
>
>My headphone jacks (and headsets) are in close proximity of the
>antenna. The jacks are located on the first former behind the seat
>and the antenna is just above all that on top of the turtle deck.
>
>I will move things around and see what happens.
Just a reminder to the List about risks for
the proximity of certain things . . .
The Comm transmit antenna is the STRONGEST
potential antagonist for deleterious effects
of EMC in the airplane. Microphone wiring
(indeed all audio wiring) is a close second
place to thermocouple wiring for most likely
victims to RF interference.
The mic and thermocouple wires are generally
limited as to routing and connections. The
antenna is by far the easiest thing to get
as far as practical from the firewall and
cockpit.
Bob . . .
////
(o o)
===========o00o=(_)=o00o========
< Go ahead, make my day . . . >
< show me where I'm wrong. >
================================
Message 14
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Subject: | Feedback while transmitting |
Just a reminder to the List about risks for
the proximity of certain things . . .
The Comm transmit antenna is the STRONGEST
potential antagonist for deleterious effects
of EMC in the airplane. Microphone wiring
(indeed all audio wiring) is a close second
place to thermocouple wiring for most likely
victims to RF interference.
The mic and thermocouple wires are generally
limited as to routing and connections. The
antenna is by far the easiest thing to get
as far as practical from the firewall and
cockpit.
Bob
Would I be correct in assuming that there should be very little interference
picked up in the mic and thermocouple wires if they are run next to the com
coax, as long as they are not near the antenna, i.e. bundled together behind
the instrument panel?
Roger
Message 15
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Subject: | I need a larger photo, please |
Quick question Matt....did you have that thing powder coated in a flat/matte
finish?
Cheers,
Stein
do not archive
Message 16
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I'm piecing together an HID landing light system and need to decide between
D1S and D2S bulbs. D1S has the igniter in the bulb, and D2S has it in the
ballast. Is there any advantage in eliminating the relatively short
high-voltage run between the ballast and bulb by using the D1S type? The
bulb and ballast will be in the wingtip along with a VOR antenna. Will the
bulb type make a difference if I decide to install a wig-wag flasher?
David Barrett
RV-7 Wings
Message 17
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Subject: | Re: HID bulb types |
flylists(at)dbarrett.net wrote:
> I'm piecing together an HID landing light system and need to decide between
> D1S and D2S bulbs. D1S has the igniter in the bulb, and D2S has it in the
> ballast. Is there any advantage in eliminating the relatively short
> high-voltage run between the ballast and bulb by using the D1S type? The
> bulb and ballast will be in the wingtip along with a VOR antenna. Will the
> bulb type make a difference if I decide to install a wig-wag flasher?
>
> David Barrett
> RV-7 Wings
The noise difference between D1S and D2S is significant, especially if pulsing
because of the noisy on pulses. D1S is what you definitely want with the high
voltage igniter at the bulb, not in the ballast.
If you use D2S anyway, at least make sure the HV cable to the bulb and the socket
are shielded.
The bulb types will not matter for wig-wag. D2S or D1S are both ok for that as
long as you warm the bulbs up (steady on) for 20 seconds minimum and 30 seconds
is even better, before you start wigwag. Make sure you are pulsing at about
1Hz (no more than 1/2 second off on each channel and at least 1/2 second on for
each pulse). This is for good bulb life.
Many HID ballasts will have a short life if you wig-wag. Most of them (automotive)
were not designed for this punishment. The SAE design specs for Automotive
ballasts are only ~20,000 starts.
That is one of many reasons why XeVision designs and makes our own ballasts. Designed
from the start (ground up) for Wig-wag capability. Also, on our newest
ballast systems, it is not required to interrupt main power to the ballast for
the wig-wag function. Our new XePulse II provides a very small trigger signal
to the ballast for on/off wig-wag function. This extra 3rd wire only needs to
be 20 or 22 awg for mechanical strength. Our newer ballasts use a 3 wire input
connector, 2 wires for + and - and the 3rd for the on/off wig-wag trigger. This
is a much better way to control wig-wag in HID systems. The XePulse II only
weighs about an ounce and can trigger about 250 ballasts per channel (obviously
way overkill). It is only about 1.5 X 1.5 X .75 inches and uses a 9 pin d-sub
connection.
All of this new proprietary ballast and HID wig-wag technology makes for a very
quiet (EMI / RFI) system. This wig-wag system IS patented as of Nov 10, 2009
--------
LED still has a long way to go to compete with HID as a landing light. This is
true in terms of total lumens and reach (distance).
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=278002#278002
Message 18
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Subject: | Follow Up to Power Opti-Miser |
Bob, thanks so much for replying to my post about my experience with low
power factor appliances. I see that I need to study some more so I can
understand this better. I've stubbed my toe on power factor questions
before, so I'm not surprised. You've asked good questions that I'll
address after I study up!
Thanks,
Dennis
Time: 06:10:15 PM PST US
From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
Subject: Re: AeroElectric-List: Re: Power Opti-Miser
At 11:30 AM 12/14/2009, you wrote:
>My house is not connected to the power grid, which makes me both a
>power generator and a power consumer. If we look at this issue from
>that perspective, things change.
<snip>
>My conclusion is that both sides of this camp might be at least
>partially correct. Since residential power meters measure real
>watts, the residential consumer isn't penalized for the extra power
>the utility has to generate to run bad power factor appliances.
>However, the utility has to generate the extra electricity, even
>though they aren't getting paid for it (which is already built into
>the rate structure).
The utility doesn't have to generate any extra watts. It only has
to choose wire sizes that carry an artificially high current that
doesn't participate in the running of devices with poor p.f.
> But if consumers could do something to improve the power factor
> of their appliances, it would reduce the amount of electricity
> produced, reducing the unfavorable environmental consequences of
> making electricity. That would be good for everyone (assuming the
> environmental effects of making the correction devices resulted in
> a net gain, of course).
The "goodness" comes only from the fact that the same work
can be done over smaller wires with less heating of the
wires. A significant savings when your transmission lines
are measured in miles instead of feet and transformers are
in 100's of KVAR instead of 2 KVAR.
>
>I have no opinion as to whether the devices under discussion
>actually reduce apparent watts. It may well be that the most recent
>appliances include better internal power factor correction. I know
>that the last batch of compact fluorescent bulbs I bought seem to
>have very good power factor.
Yes. And the folks who do switchmode power supplies
for computers and other electronics have been prodded
by dozens of articles for how p.f. can be improved for
over 20 years.
See chapter 11 in Volume 2 of the basic electronics
document below . . .
http://www.allaboutcircuits.com/vol_2/index.html
If your AC power generation devices are pseudo sine
wave (finely stepped square wave) then the output
power has more harmonic content than the stuff
coming out of the wall. This puts a whole new
twist on the problem of optimizing power factor.
Have you measured the aggregate power factor for
household loads on your system? It may well be that
the losses are so small that doing anything about
them is economically impractical. When talking about
small losses, keep in mind that your house wiring
is not zero ohms material. Depending on how long
the runs are, you may find that copper losses
are already significant and only slightly aggravated
by the effects of p.f.
Lord Kelvin reminded us often that without access
to the real numbers, our knowledge is of a meager
kind.
Your situation cries out for a long term study
of aggregate quality for your total household load.
A true RMS voltmeter, ammeter and power-factor meter
recording to a hard drive over a long period of time
would give you a basis for doing more detailed
studies followed up by useful changes to your
hardware.
Message 19
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Subject: | Re: Follow Up to Power Opti-Miser |
At 07:56 PM 12/17/2009, you wrote:
>Bob, thanks so much for replying to my post about my experience with
>low power factor appliances. I see that I need to study some more
>so I can understand this better. I've stubbed my toe on power
>factor questions before, so I'm not surprised. You've asked good
>questions that I'll address after I study up!
My pleasure sir. I'd like to know more about
your homepower experiences. At the least, an
off-list conversation would be welcome . . .
but I'm pretty certain that out of 1800
subscribers, there's a significant interest
in the practice and technology.
Shucks, some of the folks might have remote
hangars they'd like to "power up". What ever
you're comfortable with is fine with me.
Bob . . .
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