On Saturday afternoon, and after finishing the minor refurbishment of an HK Citation 17, I decided to dig a bit into the FM3 I snagged a few weeks ago. I have the new filter caps (restuff-size) in hand, and have ordered the new PEC modules. Interesting preliminary finds:
a) The solder throughout is very brittle, and more-or-less powders upon heating. So, quite heavily oxidized.
b) There is a thin layer of grease throughout, combined with the skunge that sticks to it. Either a smoker, or a greasy environment, or both. In any case, this one looks like a candidate for an industrial degreaser - suggestions welcome!
c) The line-cord connections (cord was cut) were so oxidized that merely pulling on them caused them to fail.
d) The line-cord was installed through a grommet, not a strain-relief.
e) The wiring, though generally neat, shows evidence of haste.
Accordingly, I am going to have to retouch the bulk of the solder connections, adding fresh solder. Especially those subject to mechanical movement or heat. The 200-watt soldering gun will be useful for those several chassis connections!
I will install a new polarized line-cord and the correct strain-relief.
Replace any dubious parts in addition to the PEC modules, key capacitors and key resistors.
All the tubes check high in the GOOD range, so they will do fine.
Refinish the top - rust and old paint removal, new paint.
Full alignment thereafter.
Total estimate, about 5 hours and $65 in all. Not bad for what will be a working unit in reasonable cosmetic condition when complete. And excellent therapy!
a) The solder throughout is very brittle, and more-or-less powders upon heating. So, quite heavily oxidized.
b) There is a thin layer of grease throughout, combined with the skunge that sticks to it. Either a smoker, or a greasy environment, or both. In any case, this one looks like a candidate for an industrial degreaser - suggestions welcome!
c) The line-cord connections (cord was cut) were so oxidized that merely pulling on them caused them to fail.
d) The line-cord was installed through a grommet, not a strain-relief.
e) The wiring, though generally neat, shows evidence of haste.
Accordingly, I am going to have to retouch the bulk of the solder connections, adding fresh solder. Especially those subject to mechanical movement or heat. The 200-watt soldering gun will be useful for those several chassis connections!
I will install a new polarized line-cord and the correct strain-relief.
Replace any dubious parts in addition to the PEC modules, key capacitors and key resistors.
All the tubes check high in the GOOD range, so they will do fine.
Refinish the top - rust and old paint removal, new paint.
Full alignment thereafter.
Total estimate, about 5 hours and $65 in all. Not bad for what will be a working unit in reasonable cosmetic condition when complete. And excellent therapy!
