On 11 Jul 2003 12:35:12 -0700, (Andy Durbin)
wrote:

I cut open about 3 bad battery packs and made provision for closing
screws. I buy the welded cells from batteries plus for aboout $30 and
solder them into my re-usable packs. There was also an optional
alkaline battery pack that takes 6 standard AA cells. I keep one in
the glider for landouts.

Since there seem to still be STS owners out there, does anyone have a
circuit diagram or other service information. I have 3 of these
radios but 2 of them have low receiver sensitivity. Tropic no longer
services STS.


Andy (GY)


I have an STS and the receiver sensitivity gradually got worse until I
could no longer get the local weather staion at the airport 3 nm away.
I took it to the local avionics shop where it showed about zero
response to inputs on the bench. I thought about it for a while then
opened it up to look for anything obvious and the little wire from the
output stage to the center of the antenna connector had come off the
circuit board. Re-soldered and instant fix!. Now picks up the local
weather station downstairs inside the workshop and generally works
great.

If you open the battery case to repalce the cells you could usefully
consider replacing the nicads with Ni-MH which now come in up to 2 A-h
type in same physical size. I think the original nicads were 600mA-h
so you will get 3 times the battery life. Have you also done the mod
to put in a switch to turn the battery off? Otherwise the internal
clock runs the battery down in storage. Alternatively remove the
battery pack for storage.

Mike Borgelt