In article .com,
"mikem" wrote:

Jonathan Goodish wrote:
...I pulled the cover on the rear bulkhead to
look at the glideslope receiver, strobe power pack, and battery.

On your alternator whine ground loop problem, check to see how the
audio gets out of the glideslope receiver to your audio panel. My
Skylane has a rear mounted battery and the Marker Beacon receiver is
mounted on an avionics shelf near the battery.

I checked this yesterday, the case of the glideslope receiver has
continuity with ground when it is isolated from the airframe mounting
brackett and the antenna is disconnected.




JKG