There is an old radio troubleshooting trick:
You use a insulated test probe, (length of solid wire set in an
insulated handle to safely handle it).
Move this to the plus end of each electrolytic cap, in turn, and see if
the hum level jumps up. Likely that cap may have dried out and changed
to lesser value if you get more hum on one than others similar.
However, as this could be linked to the direct conversion receiver; add
the RF bypass caps also, even one at a time, to see if the hum reduces.
Make sure no wiring has been moved around by earlier tinkerers. (Maybe
hard to determine on the point to point layout of early TT's.)
GL,
Stuart Rohre
K5KVH
_______________________________________________
TenTec mailing list
TenTec@xxxxxxxxxxxxxx
http://lists.contesting.com/mailman/listinfo/tentec
|