VB1001
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February 17, 2019, 09:20:05 AM

Amp belongs to this young fella played bass with us for a bit.  One day we are raging away and the amp goes FzzzzzzzzPOP with the accompanying smell of the magic smoke.  I'm like "skid it across into the shack, I'll see what I can do."

Pull it apart, the final is this monster 24pin IC with the whole output side blown off it.  At the time the part was $35 or something.  I Digikey one up and get it in <LESSON ALERT 1 !> disregarding the first law of electronic troubleshooting; Thou shall check power supply rails...

Fire it up, a slight crumble sound from the speaker then nothing.  Get to poking around, both the supply regs and some zeners have failed short and unregulated DC is present at the device...shit.

Order up those parts, hoping against hell that the $35 chip has protected itself somehow, it does have a laundry list of self protective features integrated.

About this time we started seeing another bassist.  Some of you may know how band breakups can be.  The kid took it pretty hard and broke contact.

Got the supply parts in and fired it up...nothing.  <LESSON ALERT 2 !> I have a common character flaw.  It's not that I'm a quitter so much as when I fuck stuff up due to my own laziness, inattention or stupidity it really kicks me in the balls.  Case in point; walking away from an engine assembly project, bottom end all bolted up, without wrapping it up in plastic, then diving into a fabrication project without paying attention and spraying the open engine with the grinder...that fucker is still sitting there 4 years later.

So the thing got slid under the bench and collected dust as a constant, depressing reminder of my lameitude, with the added social weight that the kid probably figures I stole it from him.

Well, I been trying to get my life together and clear out these projects that are dragging me down.  This made it to the top of the pile and it turns out the chips are EOL now and are going for $7.  So now I get to email the kid and relieve myself of the psychic weight of the whole episode.

Sorry for the uncharacteristic wall of text.

Congratulations for fixing it, repairing yourself a device always makes you feel useful, we are immersed in a great scam of programmed obsolescence, repair or rebuild something that does not work, it is incomparable, it is a good personal experience.