The usual suspects.

[wa1vwl]

Here in the North East, we've been suffering through a period of very
hot and humid (for us) weather. Dewpoints in the mid 70's. Due to
contractual obligations, I've been so busy, I haven't had time to use my
"new" SB-310. I know it worked pretty well when I acquired it a few
weeks ago. Although the S meter adjust range seemed to be a little
restricted but usable. Last weekend, I thought it would be nice to at
least listen to SW as I work at the keyboard. Well lo and behold, the S
meter was pegged below 0. The adjust pot could no-longer bring it within
range. A quick voltage check revealed that all was not as it should be.
Resistors had drastically changed value. The 33K was 39K, 100 was 110
Ohms, 68 was 86 Ohms and on and on it went. The adjust pot was
intermittent. But that wasn't the only thing. There was also a poor
solder connection involved. I guess what it shows is that there is
nothing like extreme temperatures to bring out the worst in your
equipment. I'm sure the resistors didn't change that drastically in the
3 weeks or so that elapsed but it sure didn't help. Eventually all these
things would have happened regardless. The heat and humidity simply
accelerated the process. For now I just replaced a few carbon
composition resistors with carbon film. Resoldered the poor connection
and replaced the 200 Ohm pot with one of those nice sealed units you
can't get anymore. Sure, it doesn't look like the original but it works
and will last for the life of the receiver, whatever that might be. When
I have time, I'll do a wholesale replacement of resistors with carbon
film. It won't look original but so what. I don't care about resale
value. I got in this hobby to have fun, not to wheel and deal. The goal
is to USE the equipment to do usefull work in the shack rather than
having a Shelf Queen to look at. Anyway, I've run out of shelf space :-)

73/Gerry/W1ID

Sponsored by the City of Tempe 

Listserver Submissions:  heath at listserv.tempe.gov
Listserver Subscription: listserv at listserv.tempe.gov - "subscribe heath 'name' 'call'"
Listserver Unsubscribe: listserv at listserv.tempe.gov - -"signoff heath"