LHanson
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The story:
I picked up a Fender Bandmaster blackface back in, eh, 1984 or so. Used it to back up a Marshall 50, and for the occasional C & W gig. After a while, it started blowing fuses. Quickly got progressively worse, until the fuses would blow as fast as a slo-blo blows. Put the amp up, gonna get it fixed someday.
Someday arrived this month. Got it out, noticed 2 of the PS caps are rolling around in the bottom of the cabinet. Not good. The 3rd is hanging by one lead, and it is obviously cold-soldered by someone who doesn't know what is going on, much like me.
I obtain a copy of A. Pittman's book, and find the schematic. The PS caps are supposed to be 20 Microfarad, 525 volts DC. I know I should recap the thing, but impatience and stupidity gets the better of me. I resolder them, and CAREFULLY fire up the amp, all controls on 1. OK in standby. Let it warm up 10 minutes, plug a guitar cord in, use insulated pliers to flip on the standby switch.
After 20 seconds of careful observation, I discover a little smoke out of the PS caps (saw that one coming, didn't ya?) Power down, unplug, fan smoke away (wasn't really that much).
Then I go on the cap hunt.
So far the closest I have come is 450 volt 20 microfarad. The schematic seems to indicate 440 will be the highest voltage in the chassis, but +- 20%.
OK to try, or order the right (or close) caps online?
I picked up a Fender Bandmaster blackface back in, eh, 1984 or so. Used it to back up a Marshall 50, and for the occasional C & W gig. After a while, it started blowing fuses. Quickly got progressively worse, until the fuses would blow as fast as a slo-blo blows. Put the amp up, gonna get it fixed someday.
Someday arrived this month. Got it out, noticed 2 of the PS caps are rolling around in the bottom of the cabinet. Not good. The 3rd is hanging by one lead, and it is obviously cold-soldered by someone who doesn't know what is going on, much like me.
I obtain a copy of A. Pittman's book, and find the schematic. The PS caps are supposed to be 20 Microfarad, 525 volts DC. I know I should recap the thing, but impatience and stupidity gets the better of me. I resolder them, and CAREFULLY fire up the amp, all controls on 1. OK in standby. Let it warm up 10 minutes, plug a guitar cord in, use insulated pliers to flip on the standby switch.
After 20 seconds of careful observation, I discover a little smoke out of the PS caps (saw that one coming, didn't ya?) Power down, unplug, fan smoke away (wasn't really that much).
Then I go on the cap hunt.
So far the closest I have come is 450 volt 20 microfarad. The schematic seems to indicate 440 will be the highest voltage in the chassis, but +- 20%.
OK to try, or order the right (or close) caps online?