Hello Velleman Community Forum!
A few months ago I successfully built a working K8060 amplifier kit which at the time didn’t seem to have any issues. I haven’t used it much until yesterday at which point when testing it at full volume something failed blowing a fair few semiconductors and the fuse.
So long story short - I’ve read that replacing all the semiconductors is the way to go but I can’t be sure of what caused the problem and that the same thing won’t happen again.
I’ve insured that common mistakes weren’t made: transistors were all in the right place, in proper contact with heatsink, correct dual 30v transformer, bias set correctly, impedance of speaker wasn’t too low, no cold soldering or modifications to the circuit etc
What i’ve found so far is that TIP147 and TIP142 have both shorted, bc547b and bc639 aren’t giving any reading at all, one of the 3300uf 50v caps reads 400 ohms in one direction and 200 in the other (which i assume isn’t expected) and both the 0.47 wirewound resistors read 1 ohm (which I also assume indicates failure…)
I had the speaker connected up via a low pass filter - could this have been the culprit?
Could I get any further advice, pointers or information? I assume that correctly assembled the kit should run at full volume for a good long while before running into any trouble?
Would really appreciate some help!
Cheers
Jamie