Avionics (Radio Problem) Narrowed Down... I Think???

I didn't mean to start an argument, I just wanted to know what I was dealing
with. Now that I know it is a relay, I can tell you how to replace it with
a genuine Radio Shack part if you wish. Give me the manufacturer and part
number again and I'll go back into the dusty part of the library and see if
I can find an old data sheet. I can then tell you how to cobble a
replacement part in.

Jim


"three-eight-hotel" wrote in message
ups.com...
I think "relay" is the correct terminology for this component. I
thought they were referred to as "relay switches", but all sites I have
seen do refer to them as "relays".

We routinely use relays in audio panels for the simple reason that the mic
audio is a rather finicky beast that requires metal switching to perform
reliably. Trying to do it solid-state is a recipe for failure.

Jim




"TaxSrv" wrote in message
...
"RST Engineering" wrote:
What is a relay switch? I've never seen one. I've seen
relays. I've seen switches. I've never seen a relay switch.


A quick Google shows the R40-etc. is a discontinued relay. It
would seem like a Rube Goldberg setup for a simple audio switching
panel. Unless it fancily switches comm 1/2 with simple pushbuttons
and indicator lights. Thence a latching relay, or more Rube
Goldbergian, with a monostable and a flip-flop? But if it has a
BOTH feature, then how we do that? :-)

Reg,
Fred F.

I can tell you how to replace it with a genuine Radio Shack part if you wish

That would be awesome, if for nothing else a backup if this thing
starts to mis-behave again. Since fiddling with the relay at the
restaurant it hasn't yet failed, but that was only 25 minutes of
flying, post fiddle...

Give me the manufacturer and part
number again and I'll go back into the dusty part of the library and see if
I can find an old data sheet. I can then tell you how to cobble a
replacement part in.

I'm going up tomorrow and will post everything I can find... AMF
Potter Brumfield R40-E1-X4 was the only thing I can recall seeing, but
I'll take a look again. Definitely no manufacturer name on the audio
panel itself???

Thanks!
Todd

The info off the relay says:

AMF Potter & Brumfield
R40-E1-X4-V200 12VDC

7705

Thanks!
Todd

And I can't find my old P&B catalog to save my soul. It may have been a
victim of one of my "haven't used it in twenty years, throw it out" library
purgings of last year. Best I can find is that it is a 3 pole, double throw
relay. That sort of gobs up the works, but we can still find a replacement
if you will tell me how it connects into the panel. Is it a plug in? Bolt
down? Can you take a picture of it and post it somewhere? We can cobble
anything if we know the form factor, even if it means three SPDT micro
relays in the same space.

Jim



"three-eight-hotel" wrote in message
oups.com...
The info off the relay says:

AMF Potter & Brumfield
R40-E1-X4-V200 12VDC

7705

Thanks!
Todd

Thanks for looking Jim!

I found a link for someone that sells components and requested to have
a relay shipped to me. I'll probably put that one in and keep the
other one for a backup, although I'd be surprised if this is a common
problem given the number of Cessna audio panels that are out there and
still working...

I am probably going to try and find another audio panel, with marker
beacons and the componentry to support another COM, so I can throw one
in some day. I'd love to bite the bullet and upgrade to a newer audio
panel, but that would require a rewire and would be quite expensive!
What I have in there now serves my purpose, when it all works!!! ;-)

Thanks again for all of the input! I will post an update on how things
go, once I've had a chance to replace the relay. As for the immediate
problem... it has not come back, since we fiddled with the current
relay, although, I've only got about 3 hours of flight time since.
None-the-less, I wasn't getting that much functionality out of it, when
it was intermittently working!

Best Regards,
Todd

Received a new relay on Wednesday, plugged it into the audio panel and
slid the audio panel back into the stack this morning.

Took off out of Georgetown, after making my radio calls (with sidetone
on every call), turned downwind, and set the trim for a 300 fpm climb,
while I started tuning in frequencies. First SAC ATIS.... Loud and
Clear. Second NorCal approach... Loud and Clear. Back to GT freq
123.05 and heard numerous calls at Marysville and Cameron Park.

As I continued to climb, through 7000 feet, I considered turning right
45 degrees and heading over Lake Tahoe as the winds were calm and the
weather was gorgeous. As I prepared to turn, I noticed Nevada Co.
airport and Grass Valley off to my immediate left. Tuned into the
local frequency, let them know my position and asked for a radio
check.... LOUD AND CLEAR!

Waved hello to Jim (probably didn't see me), and decided I would head
back home and get some chores done, even though I could have flown all
day! Did I mention it was gorgeous out there?

Thanks for everyone's patience and help over the last few months! I'm
so glad to think this nightmare could finally be behind me, and am
ready to head up and get that instrument currency, now that I can
communicate!!! I just hit 6 months without my approaches a few weeks
back, so I'll have to go up with a friend and get some hood work done.
After that, I'm looking for some of that Valley fog, as I'm ready for
some actual!!!

Best Regards,
Todd

On 11/19/2005 4:06 PM, three-eight-hotel wrote:
Received a new relay on Wednesday, plugged it into the audio panel and
slid the audio panel back into the stack this morning.

Took off out of Georgetown, after making my radio calls (with sidetone
on every call), turned downwind, and set the trim for a 300 fpm climb,
while I started tuning in frequencies. First SAC ATIS.... Loud and
Clear. Second NorCal approach... Loud and Clear. Back to GT freq
123.05 and heard numerous calls at Marysville and Cameron Park.

As I continued to climb, through 7000 feet, I considered turning right
45 degrees and heading over Lake Tahoe as the winds were calm and the
weather was gorgeous. As I prepared to turn, I noticed Nevada Co.
airport and Grass Valley off to my immediate left. Tuned into the
local frequency, let them know my position and asked for a radio
check.... LOUD AND CLEAR!

Waved hello to Jim (probably didn't see me), and decided I would head
back home and get some chores done, even though I could have flown all
day! Did I mention it was gorgeous out there?

Thanks for everyone's patience and help over the last few months! I'm
so glad to think this nightmare could finally be behind me, and am
ready to head up and get that instrument currency, now that I can
communicate!!! I just hit 6 months without my approaches a few weeks
back, so I'll have to go up with a friend and get some hood work done.
After that, I'm looking for some of that Valley fog, as I'm ready for
some actual!!!

Best Regards,
Todd


That's great news. I had a problem with an ANR headset early in
my training that almost caused me to stop. Luckily, before I did,
I tried out a cheapo pair of non ANR and have never gone back.

To this day, I still marvel over how well I can hear each communication.
It's amazing how precious it can be once you've had to do without for
some time!

By the way, do you already have someone lined-up for the instrument
practice?

--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

To this day, I still marvel over how well I can hear each communication.
It's amazing how precious it can be once you've had to do without for
some time!

No kidding! I've been dying to do some practice IFR flying, but afraid
of having to go the handheld and tell ATC that I'm just going to resume
own nav back to Georgetown, rather than trying to concentrate on
approaches and fuss with a handheld (and not be able to communicate to
the guy in the right seat). I sooooo hope this is the end of it, and I
can get back to hearing and talking to everyone!

By the way, do you already have someone lined-up for the instrument
practice?

Someone that's always willing, but not necessarily lined up...

If you're up for some evening flying, we should get in touch.

Best Regards!
Todd

On 11/19/2005 5:24 PM, three-eight-hotel wrote:
To this day, I still marvel over how well I can hear each communication.
It's amazing how precious it can be once you've had to do without for
some time!

No kidding! I've been dying to do some practice IFR flying, but afraid
of having to go the handheld and tell ATC that I'm just going to resume
own nav back to Georgetown, rather than trying to concentrate on
approaches and fuss with a handheld (and not be able to communicate to
the guy in the right seat). I sooooo hope this is the end of it, and I
can get back to hearing and talking to everyone!

By the way, do you already have someone lined-up for the instrument
practice?

Someone that's always willing, but not necessarily lined up...

If you're up for some evening flying, we should get in touch.

Weekends are better, but I would like to help if you need it.
Contact me off-list any time.



Best Regards!
Todd



--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA