Today's Message Index:
----------------------
1. 06:58 AM - Re: Altitude Encoder Readout (Joe)
2. 07:01 AM - Re: Re: Electrical Problem (Robert L. Nuckolls, III)
3. 07:20 AM - Re: Switch wiring conundrum (Robert L. Nuckolls, III)
4. 07:46 AM - Re: Icom A-210 intercom (Robert L. Nuckolls, III)
5. 07:55 AM - Re: Altitude Encoder Readout (Robert L. Nuckolls, III)
Message 1
INDEX | Back to Main INDEX |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Altitude Encoder Readout |
Larry Sharratt,
I purchased the kit and built it and it works great. I doubt that the
kit is available now but it would not hurt to ask. The name of the
company was Airpar. Contact:
Fred N Wimberly (703) 979-2483
PO Box 2755
617 21st St S
Arlington, VA 22202-2732
I still have the construction manual and parts list. However, this will
not do you much good without the PROM, the "brains" of the kit. The
PROM must be programmed with the gray code, not an easy task (beyond my
capability). If you really want to build an Altitude Encoder Read-Out
and Fred Wimberly can not help, then perhaps a knowledgeable person on
the AeroElectric website can help.
Joe Gores
Message 2
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Electrical Problem |
At 04:06 PM 7/5/2009, you wrote:
>Joe,
>
>I instruct in C172s with G1000s and that happens
>on a regular basis. I dont think its really a
>problem, it basically means the battery is fully
>charged and at low RPMs its actually supplying
>a few electrons more than the alternator. As
>long as it goes away as soon as the RPMs come
>up, I dont consider it an issue. Hopefully Bob will confirm
It's a good hypothesis but would be confirmed by
seeing the bus voltage fall below that value at
which the battery will deliver significant energy,
i.e. 13 volts.
Back when ALL our cars were fitted with generators
and most were fitted with battery ammeters, it was
quite common to see the battery ammeter go into
the discharge zone at curb idle . . . especially
at night with lights and perhaps heater blowers
turned on too.
As soon as the car began moving, generator speeds
would be sufficient to pick up all vehicle loads
and the battery ammeter might even show a short
duration "charge" transient as energy withdrawn
from the battery at the last stop light was replaced.
Ideally, after some significant interval of driving,
the battery becomes fully charged and the battery
ammeter needle assumes the "all is well" position
very close to zero with a slight + bias.
These same battery ammeters were never fitted with
zero adjusters. Therefore it is possible that some
devices would have different presentations for
the "all is well" condition . . . they might even
have a slight - (discharge) presentation.
Until one conducts a no-wires-inside-the-
hall-sensor experiment, the systems zero-current
presentation is not known. Alternators were praised
for their ability to maintain system voltage at
or above battery discharge thresholds. So unless
the bus voltage sags at idle due to ship's loads
exceeding alternator capability at that RPM, then
ammeter offset errors are suspected.
This is one of the "problems" with integrating
modern instrumentation technology into our airplanes.
System readings that used to be presented to us by
some fat needle on a tiny gage setting inside the
green arc have been replaced with digits and
decimal points. Unless those new instruments are
favored with offset and scale factor calibration
adjustments, then it's possible that their
presentations could be sufficiently in error as to
raise concerns. The way to resolve the issues is
with comparative measurements against other instruments
of known characeristics.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 3
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Switch wiring conundrum |
At 11:25 PM 7/4/2009, you wrote:
>Thanks to everyone for their thoughts.
>
>I "bit the bullet" and celebrated the 4th of July by spending a
>delightful 5 hours under my instrument panel moving components /
>rewiring / etc to shoe-horn in room for another switch -- which got
>in there with 0.05" to spare. God then smiled on me & miraculously
>there were even two new 2-3 switches squirreled away in the back of
>the tool chest to allow me to directly replace the old 2-10.
I think this is a good move my friend. In about a year,
I'll be able to share the unfortunate details on an electrical
system wherein the system designer took ingredients for
biscuits, bread, hot cereal, and dumplings and
stirred them into a new product that turned out to
be less than palatable . . . and was in fact
hazardous to health.
It's in our best interests to first consider the
manufacturer's instructions for integrating any critical
components into an airplane. But it does not automatically
follow that the manufacturer of a product is well versed
in the art of failure mode effects analysis and design
for failure tolerance. We should strive for the lightest,
least expensive and least numbers of parts that minimize
the need for pilot attention and intervention. I.e. the
elegant solution. EVERY design is fair game for critical
review.
There's no such thing as a SAFE airplane, automobile,
handgun or skateboard. There are considerations of design,
installation, operation and environment that always yield
to logical incorporation of simple-ideas into minimum risk
recipes for success.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 4
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Icom A-210 intercom |
At 11:09 PM 7/4/2009, you wrote:
><chris_sinfield@yahoo.com.au>
>
>Hi
>speaking of intercoms, I just bought a new Icom 210 and want to put
>it into my 2 seater. Does the 2 place VOX system work OK should I
>have a seperate 2 place intercom.
>I just want to be able to talk to my pax, TX from either position
>and have an MP3 input. to both..
I think the A210 shares an intercom feature with many
other compact comm radios like the Microair, X760, etc.
The intercom is a "hot mike" system using the radios
side-tone circuits that are energized with a push-to-talk
button. I.e., with the intercom button pressed, both
individuals hear each other and themselves speak.
Unless the noise cancelling capability of the headset
microphones is quite good, you would not want to leave
the system in the "intercom hot" condition all the time.
You'd get tired of listening to the cabin noise (or
even hearing the passenger chew his/her gum).
I've flown airplanes with PTT intercoms and personally,
like them. It cuts down on idle chatter (due to the
inconvenience of having to operated the button), and
eliminates the VOX setting creep induced by changes in
cabin noise levels.
Most folks don't like this feature . . . I note that
I didn't even show the PTT intercom button to pin
10 in my wiring diagrams. I'll suggest you give it
a try. You can always add a VOX based intercom later.
Your music system can be injected to one of the
aux audio input pins C, D or 3.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 5
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Altitude Encoder Readout |
At 08:55 AM 7/9/2009, you wrote:
>Larry Sharratt,
>
>I purchased the kit and built it and it works great. I doubt that
>the kit is available now but it would not hurt to ask. The name of
>the company was Airpar. Contact:
>Fred N Wimberly (703) 979-2483
>PO Box 2755
>617 21st St S
>Arlington, VA 22202-2732
>
>I still have the construction manual and parts list. However, this
>will not do you much good without the PROM, the "brains" of the
>kit. The PROM must be programmed with the gray code, not an easy
>task (beyond my capability). If you really want to build an
>Altitude Encoder Read-Out and Fred Wimberly can not help, then
>perhaps a knowledgeable person on the AeroElectric website can help.
I recall seeing various display projects over the years
but was unable to "put my hands" on one quickly. There
IS an interesting product designed by a friend of mine
that reads the output of your transponder's reply burst.
See:
http://www.airsport-corp.com/
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|