need some capacitors, can't find online.

Many use pain silicone rubber. There are clamps available as well. Sometimes its preferable not to drill holes
 
Usually caps mounted to PCBs don't need adhesive at at. The solder connections are adequate. Manufacturers used adhesive so they could place many parts on board and not worry about them falling out before soldering. Unfortunately some were reactive and corrosive and over time destroyed components and traces.
 
I got the new capacitors to replace the leaky ones.

I ended up filing the tangs of the large capacitors so they would fit into the holes of the pc board and they fit fairly well. That is the good news!

The bad news is that I fupped-duck the amp in another way.

I let the amp sit at idle to warm up for about ten minutes so I could measure the idle current. I accidentally placed the probes of the multi-meter on the wrong resistor and POOF! The fuse blew! DAMN IT!!!

The replacement fuse blew immediately on startup. The amp will not power up at all.

So, have you guys any thoughts on what I should check to figure out how to repair this thing? Remember I am a totally noob to this sort of thing.)

Thanks again in advance for any help!
 
may have blown the main output devices and drivers . you need to test all of them for short circuits . what exactly did you short out ?
 
may have blown the main output devices and drivers . you need to test all of them for short circuits . what exactly did you short out ?

I tried measuring a resistor. I do not know what all was shorted out.

By "output devices," do you mean the output transistors? If so, how do I test them? Same with the "drivers." How do I check them?

Thanks!
 
Hi. Happened to me, the exact same thing. Accidentally dropped a meter probe on the wrong spot while adjusting idle current and blew output transistors in one channel... After that the Amp won't turn on after that.
The place where made the short circuit might tell you which channel blew. Or just check for short circuit at the transistor pins, it's really easy with the meter. Most likely you have to change a pair of transistors.
Don't forget the mica insulators and new emitter resistors as well as they most probably overheated and increased value out of spec.
 
WHY do people think filter caps bulge on top when bad???

There is NO reason they would.
The "bulging" people see is the plastic cap over the can (insulation).
The caps have a vent hole in the bottom, covered with rubber. THAT will vent any pressure LONG before the metal can will deform.

People really need to STOP judging caps by looks.
You cannot SEE bad electronics unless they are physically exploded or burnt or charred from overheating.
Some parts run hot and discolor but are fine so even that is not "the problem" in many cases.

I beg to differ.

Since the advent of mounting capacitors on pcb's,most manufacturers have done away with lead-end rubber vents on radial leaded caps. They were considered to be ineffective and unsafe due to the end of the cap being held against,and often sealed with glue, to the board.

The present day (actually,for many decades) safety vent is the stamped crease in the end of the aluminum can,which splits under extreme pressure. As this is the only point of pressure release,caps with bulging ends are,in fact,showing that they have clearly been stressed beyond their design limit.Only in extreme cases do the safety seams actually split,and burst caps are rather rare.

Aluminum+Electrolytic+-+Venting+failure.jpg
 
Part of "Qualification" testing for a design and product is putting the product on a vibration table. Then the Product is subjected to ever increasing vibration and a frequency sweep, on varying angles, to see what will fail first. Generally it is the heavier, larger 'lytic caps breaking off and flying around. Glue is added to parts that break loose, and the test is re-performed if the same tests show no breakage or damage with the same energy, that part of "Qual" testing is successful, and testing proceeds to temperature cycling, humidity cycling, salt spray, etc.

Units that will likely not be subjected to the rigors of rough shipping should be fine without glue.

Enjoy,
Rich P
 
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