Fixing the Transponder with Duct Tape and Aluminum Foil

It seemed to me that the most likely culprit was that last two inches of
unshielded wiring and the unshielded connector...especially since they
were
the closest part of the wiring harness to the transponder.

So, today I took a roll of aluminum foil out to the airplane and wrapped
foil around the back of the radio, leading it down the wires until it
contacted the braid. Duct tape, of course, to hold it in place.

I'm happy to report that this solved the problem. Radio signals were
perfectly clear.

I figure the foil isn't worthwhile as a permanent solution. A guy at the
airport suggested using aluminum window-screen material. It appeals to
the
cheap side of me.

The inside? :-)

You get more flying time per buck than anybody I know. What do you do with
all the money you save?

Ed Wischmeyer

On Fri, 12 Mar 2004 19:30:24 -0700, Ed Wischmeyer
wrote:

I figure the foil isn't worthwhile as a permanent solution. A guy at the
airport suggested using aluminum window-screen material. It appeals to
the
cheap side of me.

The inside? :-)

You get more flying time per buck than anybody I know. What do you do with
all the money you save?

I sit in closet all evening, rubbing my face with dollar bills. :-)

Ron Wanttaja

Jim Weir wrote in
:

As I recall, that flipflop triggers a timer (10 seconds???) that sends
the ident bit until timeout. Bose' book confirms what I remember
also.

That sounds likely. [Book? You have a book? G]

The main point, relative to this thread, is that it does NOT cause the
transponder to transmit anything in and of itself. It only controls what
gets sent upon interrogation.

jmk

-
-That sounds likely. [Book? You have a book? G]

Bose, Safford, Friedman, Krause, Jasik...


-
-The main point, relative to this thread, is that it does NOT cause the
-transponder to transmit anything in and of itself. It only controls what
-gets sent upon interrogation.

That's the truth.


Jim



Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

Ron:
Most hardware stores have copper and AL screenwire. With copper you can
solder Your cage to fit.

"Ron Wanttaja" wrote in message
news
I'd installed my new Microair transponder a month ago, but have been
having
troubles with interference. The transponder was inducing bad clicking
sounds into the comm radio receiver, making the radio difficult to
understand.

I couldn't really blame the Microair, since the Terra transponder I'd had
before did exactly the same thing. But I'd been hoping the new
transponder
and installation would eliminate the problem...especially since I'd
reworked all the transponder wiring and moved the antenna to a different
location. But the interference continued.

The main suggestion I got from the avionics guys around here is that the
transponder was interfering via the cables running to the headset jacks.
I
installed shielded braid over those cables, though, and the problem
continued.

All the electrical connections to the radio (except the antennas) are made
via an unshielded flat connector. Since the wires had to spread out to
fit
the connector, I hadn't been able to run the braid all the way to the
radio...it terminated about two inches away, and I ran a ground wire from
the braid to the radio chassis.

It seemed to me that the most likely culprit was that last two inches of
unshielded wiring and the unshielded connector...especially since they
were
the closest part of the wiring harness to the transponder.

So, today I took a roll of aluminum foil out to the airplane and wrapped
foil around the back of the radio, leading it down the wires until it
contacted the braid. Duct tape, of course, to hold it in place.

I'm happy to report that this solved the problem. Radio signals were
perfectly clear.

I figure the foil isn't worthwhile as a permanent solution. A guy at the
airport suggested using aluminum window-screen material. It appeals to
the
cheap side of me. Any drawbacks, or suggestions for alternates?

Ron Wanttaja

Ron:
Last time I was in the local Aerospace store they had it. But You can
get it from:
http://www.twpinc.com/twp/jsp/product.jsp?type=3

"Ron Wanttaja" wrote in message
news
I'd installed my new Microair transponder a month ago, but have been
having
troubles with interference. The transponder was inducing bad clicking
sounds into the comm radio receiver, making the radio difficult to
understand.

I couldn't really blame the Microair, since the Terra transponder I'd had
before did exactly the same thing. But I'd been hoping the new
transponder
and installation would eliminate the problem...especially since I'd
reworked all the transponder wiring and moved the antenna to a different
location. But the interference continued.

The main suggestion I got from the avionics guys around here is that the
transponder was interfering via the cables running to the headset jacks.
I
installed shielded braid over those cables, though, and the problem
continued.

All the electrical connections to the radio (except the antennas) are made
via an unshielded flat connector. Since the wires had to spread out to
fit
the connector, I hadn't been able to run the braid all the way to the
radio...it terminated about two inches away, and I ran a ground wire from
the braid to the radio chassis.

It seemed to me that the most likely culprit was that last two inches of
unshielded wiring and the unshielded connector...especially since they
were
the closest part of the wiring harness to the transponder.

So, today I took a roll of aluminum foil out to the airplane and wrapped
foil around the back of the radio, leading it down the wires until it
contacted the braid. Duct tape, of course, to hold it in place.

I'm happy to report that this solved the problem. Radio signals were
perfectly clear.

I figure the foil isn't worthwhile as a permanent solution. A guy at the
airport suggested using aluminum window-screen material. It appeals to
the
cheap side of me. Any drawbacks, or suggestions for alternates?

Ron Wanttaja