A Speco PSR-50?

>>935099
Could be a failed rectifier if it blew up several capacitors? effectively feeding the DC circuit AC.

>>935099
Can you take a picture of the part that exploded?

File: IMG_20160123_2037452.jpg (1MB, 2688x1520px) Image search: [Google]

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This is the part that exploded

It has large capacitors on the bottom side

>>935103
So just the capacitors exploded or a component on that board?

File: IMG_20160123_203808.jpg (2MB, 2688x1520px) Image search: [Google]

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This is the model

>>935103
Discharge those capacitors and flip the board over, lets see what went pop.

I won't be able to check fully until later today. Was working late and will need to sleep soon, but It looked like a capacitor blew with the sudden eruption of smoke

I'll take it out and take more thorough pictures for you guys

nice haul

linear supplies are much nicer/cheaper to fix than switchers

Thanks for the compliment

I actually got...2 psr-50 voltage regulators, 6 speaker amps, 3 large rolls of copper insulated copper wire, an iron shelf, over 400 speakers (all broken, I checked), 2 car radios, A crap-ton of screws, and the shop owners old speaker tester.

a cursory look at the circuit suggests the voltage control is done on the 120V side, like with a Triac lamp dimmer, which kinda makes sense coz your currents are 10 times lower. presumably the parts in heat sinks at the back are diodes. the blue wires carry AC to them, and they come out as unfiltered DC on the red wires.

>>935109
Things to check first.

>Capacitors
They go bad with age and if it hadn't been powered up in a long time the shock of suddenly having voltage across them could of broken down the dialectic.

>bridge rectifier
These do go bad especially on big ass high current supplies like this, check it. If one of the internal diodes broke down and AC got to the capacitors it could have caused that explosion.

>foreign objects
Maybe some conductive shit has fallen inside of the unit during its storage and transportation years?

>loose wires
could have snapped off and is touching something at a different voltage.

>somebody's been fiddling
self explanatory, average Joe has had a go at fixing it but made things worse.

>>935121
Could just be a control voltage winding that terminates on the same side as the primary coil? I know the US uses white and black but you can see the brown and blue mains underneath them connecting to the transformers primary coil.

Also the black connects to a trace that is electrically connected to the orange wire.

Ok, those options sound good. I'll give it a check later today and will post some more in depth pictures

For now, I got to sleep

ok, had a slight time delay, but I should be able to get a picture of it tomorrow morning

File: IMG_20160125_094306[1].jpg (1MB, 2688x1520px) Image search: [Google]

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Ok, got the pictures and here is the main problem

There are two breaks in the back of the circuit board and one blown capacitor

File: IMG_20160125_094829.jpg (1MB, 1520x2688px) Image search: [Google]

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And this is the blown capacitor. There are six in total, five of these and one smaller one

>>935906
Check the bridge rectifiers, a lot of current would have been needed to pop those traces.

File: LotsOfFail.jpg (338KB, 450x3082px) Image search: [Google]

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>>935906

What this anon says
>>936314

yeah, the blown traces are not the problem, but the consequence of the problem. *way* too much current was going through there

>pic unrelated

>>936314
>>936319
Could have been the other capacitors discharging into the failed one? It still seems like an usually high current though to have popped those thick tinned traces, 25v @ 10,000uF is only 3.125 joules.

File: cap board.png (25KB, 937x530px) Image search: [Google]

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>>935921
>>935917
>>935906
I think this is how that capacitor board is configured but you should double check.

The main DC bus winding looks to be using two separate bridge rectifier diode bricks to spread the power dissipation, but only two of the diodes are being used if there is an unconnected terminal.

That smaller 3300uf capacitor must be for a control winding of sorts and is at a higher voltage than the main DC bus.

>>936338
Ignore the "+" polarity markings on the transformer symbol.

File: IMG_20160125_094702.jpg (897KB, 2688x1520px) Image search: [Google]

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In the other psr-50 power supply is this one

Has the same caps, but is a little different on top