ADF Problem

The ADF in our Cessna 172 isn't working right. Yes, we can receive the
audio but the indicator only swings through 180 degrees on the indicator
(from 180 to 360) and doesn't point in the direction of the transmitter.
We tried repalcing the indicator with no improvement. Can someone
ewnlighten us as to other remedies? Simple antenna checks? Clues? All
in all, it's not worth spending a pile of money on an ADF. Of course,
we can still get the football and baseball games on the radio, so it's
at least worth something. Plus it fills a spot on the stack.

Thanks

Al
1964 Skyhawk
Spokane

On Nov 23, 3:50 pm, Al wrote:
The ADF in our Cessna 172 isn't working right. Yes, we can receive the
audio but the indicator only swings through 180 degrees on the indicator
(from 180 to 360) and doesn't point in the direction of the transmitter.
We tried repalcing the indicator with no improvement. Can someone
ewnlighten us as to other remedies? Simple antenna checks? Clues? All
in all, it's not worth spending a pile of money on an ADF. Of course,
we can still get the football and baseball games on the radio, so it's
at least worth something. Plus it fills a spot on the stack.

Thanks

Al
1964 Skyhawk
Spokane

Next time you fly, switch off the ALT half of the Master Switch. If
the needle then points to the station, your alternator filter has
fallen off or failed.

Check the antenna connectors. My Archer had a loop antenna mounted on the
belly and a sense antenna mounted from cabin top to the vertical stabilizer.
When I unscrewed and removed the loop antenna I found quite a bit of
contact corrosion. The female side of the plug was a mini tube socket that
I was able to buy at a local electronics store.

I eventually pulled out the ADF and installed an Air Gizmo panel mount for
my 496.

--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

On Nov 23, 4:27 pm, "Mike Noel" wrote:
Check the antenna connectors. My Archer had a loop antenna mounted on the
You didn't say what kind it was, but as the other poster said it
relates to
the antenna. There are a pair of coils at right angles. You symptom
suggests
that the fore aft one is OK but the other one is dead either for
connection reasons
or some other failure.

You could check it with an ohmmeter.


Bill Hale


belly and a sense antenna mounted from cabin top to the vertical stabilizer.
When I unscrewed and removed the loop antenna I found quite a bit of
contact corrosion. The female side of the plug was a mini tube socket that
I was able to buy at a local electronics store.

I eventually pulled out the ADF and installed an Air Gizmo panel mount for
my 496.

--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

On Fri, 23 Nov 2007 16:27:42 -0700, "Mike Noel"
wrote:


I eventually pulled out the ADF and installed an Air Gizmo panel mount for
my 496.

Funny you should mention that...

Our plane had the ADF removed in the mid-90's by it's previous
owners, because the never needed it. We have dual VOR's, DME, and a
handheld GPS similar to yours.

The airport I fly to most often with my wife has "ADF Required" on the
ILS. ;^(