As I remember, I had 4 variable output power supplies before I moved, one being an HP triple output variable P/S. They were all HP actually, the others were just single output. I have to go to my storage and look around as none of them HAVE SURFACED YET. When I moved I had to hire some questionable individuals to help AS MY REAL FRIENDS WERE NO WHERE TO BE FOUND. You ever get to a point in your life when you realize you don't really have any good friends, that it all was somehow conditional? And given the chance with the right set of circumstances, everyone of them have failed the honesty, true friend test. Which is why whenever I can, I work alone.
Ok, I made a DBT, got the pico fuses. Waiting on the bridge rectifier. I was looking closely at the amp and it looks like a couple other things might be toasty as well. Take a look at those 2 blackened resistors in the upper left corner marked R26. Are they supposed to look that way? If so, what is my next step Turk?
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R26 you say, first they are not blackened that's their native color as to the suspicion of heating we'll discover that later (it's possible that supply regulation for the pre-amp stage may be faulty)
while waiting for the bridge to arrive pull the output devices out of circuit and test them, next would be driver transistors but one thing at a time...
while waiting for the bridge to arrive pull the output devices out of circuit and test them, next would be driver transistors but one thing at a time...
It's not anything pretty as the parts are repurposed from an outdoor horse grooming station we had to remove, so it's a water resistant aluminum box with a pair of ac outlets with a switch and the box has suffered some oxidation and the bulb socket came out of some fancy lamp the had artwork on cloth panels (a square) that illuminated from the inside. Hell, I could have just taken a picture for as long as it took to describe it.
When you say remove the output devices and test them. I need specifics. Remember, I'm just a dumb robot that doesn't know much about electronics but will do whatever is needed, your the commanding brain. But I'm assuming you mean transformer, right? I did learn how to test in with an ohm meter detached. And to check output you (I) can plug the wires in directly to the outlet?
When you say remove the output devices and test them. I need specifics. Remember, I'm just a dumb robot that doesn't know much about electronics but will do whatever is needed, your the commanding brain. But I'm assuming you mean transformer, right? I did learn how to test in with an ohm meter detached. And to check output you (I) can plug the wires in directly to the outlet?
no i was meaning the output transistors.
i'm not much of a commanding "brain" and interact better with robots who have some program instructions....
what we are looking for now is a fault/problem elsewhere that would have the potential to have damaged the original bridge rectifier.
we'll also need to evaluate the main filter caps.
i'm not much of a commanding "brain" and interact better with robots who have some program instructions....
what we are looking for now is a fault/problem elsewhere that would have the potential to have damaged the original bridge rectifier.
we'll also need to evaluate the main filter caps.
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output transistors? Would they be marked with a T? Thank god for the little map on the board of what goes where, otherwise I would be more lost. They all look the same to me. So, signal flows from the pre-amp stage first, then the power section. Current goes to the power switch then the transformer, fuses, Bridge rectifier? Those transistors must be somewhere in between all that, right?
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Exactly, I was going to point out that one is made in Mexico and the other, I can't quite read, but they are different. Maybe someone tried and finally threw in the towel, which I why I seen it about to get parted out at a scrap yard. It's got to be fixable though, nothing is impossible. This will just put your knowledge to the test. And I have to be as observant as I possibly can. Thanks so far for all your help. I'm really enjoying this, I love a challenge and I'm looking forward to a victory someday soon. The parts have been cheap so far. Hopefully the transformer is still good. I was hoping that no one else had tried to fix it,, and further the damage. They must have missed something.