I've had this amp in storage since about 2000-ish. One of the power tubes shorted back then and reissues didn't exist at the time, NOS pairs were $100+, etc., etc. Anyway it worked flawlessly prior to the tube failing (one of the power tubes rattled if you had it in your hand and, sure enough, that tube eventually shorted out).
I just got new tubes in for it a couple days ago. It turned on, made sound (actually sounded good) but it was cutting out, popping, squeeling, crackling, etc. So I took tuner cleaner and sprayed down the tube sockets, scrubbed that around with the tubes, let it sit overnight. It is better now, and will sound good, quiet and consistent at low volume.
With the volume turned up to a point where the amp normally starts to distort, however, hard-hit notes will cause the same loud crackling/cutting out, pops, etc.
Secondly, the tremolo function does not work. I know the old Fender amps' tremolos always break b/c they have the optical flasher thing that always goes bad, but I don't see one inside this amp. Furthermore, when I click the foot switch, there is a momentary drop in the volume, like the tremolo should sound, but it only occurs when I hit the switch; the tremolo doesn't continue oscillating. (I did drop a nickel across the terminals on the switch, thinking the switch itself might be bad, but got no effect.)
So... this thing is pretty simple inside, circuit-wise and I can wield a soldering iron pretty well. What am I looking for to fix the two problems? I'd think caps, but, unlike the Fender caps that you visibly tell are bad (bubbles and discoloration), this thing has the metal can assembly, so I'm not sure of it...
FYI, tubes are brand new JJ 7591Ss and NOS brown base Tung-Sol 6SL7WGTs.
Here are pics of chassis insides, left to right and schematic, in case anybody "spots" something...
I just got new tubes in for it a couple days ago. It turned on, made sound (actually sounded good) but it was cutting out, popping, squeeling, crackling, etc. So I took tuner cleaner and sprayed down the tube sockets, scrubbed that around with the tubes, let it sit overnight. It is better now, and will sound good, quiet and consistent at low volume.
With the volume turned up to a point where the amp normally starts to distort, however, hard-hit notes will cause the same loud crackling/cutting out, pops, etc.
Secondly, the tremolo function does not work. I know the old Fender amps' tremolos always break b/c they have the optical flasher thing that always goes bad, but I don't see one inside this amp. Furthermore, when I click the foot switch, there is a momentary drop in the volume, like the tremolo should sound, but it only occurs when I hit the switch; the tremolo doesn't continue oscillating. (I did drop a nickel across the terminals on the switch, thinking the switch itself might be bad, but got no effect.)
So... this thing is pretty simple inside, circuit-wise and I can wield a soldering iron pretty well. What am I looking for to fix the two problems? I'd think caps, but, unlike the Fender caps that you visibly tell are bad (bubbles and discoloration), this thing has the metal can assembly, so I'm not sure of it...
FYI, tubes are brand new JJ 7591Ss and NOS brown base Tung-Sol 6SL7WGTs.
Here are pics of chassis insides, left to right and schematic, in case anybody "spots" something...