Working Man's 12 blows fuse

[J M Fahey]

Hope someone with experience will answer.

Have you ever been experienced? - J. Hendrix

Well, if you need *that* kind of fumes "experience", ahem !, can't help you.
If "solder fume" experience is enough, yes, any 8A 200V (or more) bridge that fits in there will do.
In fact an easier to find 6A unit will do nicely.
Anyway build a lamp bulb limiter, to save on fuses but more important, in patience.
Good luck.

[spsimmons]

The amp is now repaired! I used a bridge rect. that's rated at 8A/400V because that's what the store who's name starts with R keeps in stock. It powers up, stays on, amplifies bass, what more could I ask? The pots are all super scratchy from sitting for several years. They get better the more I turn them, so I figure that will go away with use.

Much thanks to everyone, couldn't have done it without you.

Now I can start a new thread for my next project.

[Fragger]

I can`t say enough about the benefits of using DeoxIT D5 on the pots., jacks and switches.

I`ve had 5 SS combos I`ve brought back from being marginally functional (distorted, intermittent, scatchy, noisy, dropped volume) to flawless.

The stuff is magic in a can.

And you can get it at the "R" place too.

[J M Fahey]

Congratulations, and I guess the part that goes

I'm new here, and pretty ignorant about amp repair.

, is quite outdated by now.
Now you clean those pots as suggested above and you have a new amp, and, of course, start reading old posts that you find interesting or useful.

[Cinemafixer]

Similar symptoms...

Hi. new to this forum, so thanks in advance. I have the same unit on my bench, a workingman's 12. There is no evidence of any heat damage to the board itself, yet I found 2 outputs shorted and bridge open. Replaced both outputs and bridge. Every other semi on the board tests OK, as do the resistors around the power section. Power the unit on, it works for a few seconds until the outputs get SUPER hot and the unit begins to hum loudly. The load seems normal. Nothing else on the board gets hot at all. Any thoughts? Thanks y'all!

[Enzo]

Hi fixer, welcome to the forum. DO yourself a favor adn start a new thread for your amp. You will get better response than tacking on the end of the 19th post of a thread that died in January.

Visual evidence is great when it exists, but MOST circuit failures don't look any different.

Until you know an amp is stable and does not put out DC, work with NO load.

Your power transistors are mounted to the heat sink, I Hope? DO not operate the circuit with the transistors in air.

Scope the output for RF oscillation.

AT the output, very important that neither R43, R44 be open. 1.5 ohm and 22 ohm respectively.

[Cinemafixer]

Thanks, Enzo - sure. I'll start a new thread - one forum I'm a member of prefers we keep threads together rather than have a zillion threads about product x,y,z... I hate that. Thanks for the suggestions - the heatsink is removed from the chassis and transistors are mounted to it. I'll check those 2 resistors, though I'm pretty sure I did already...Thanks again man.