AMP TECHS LOOK INSIDE!!!!

[theAntihero]

I got a Peavey F-800b from a formite in trade and even though it worked fine for him before it now has problems. The biggest being that it fades in and out and crackeles on note decay, the fading sorta sounds like a vibrato pedal. The other problem is it randomly lights up inside when i turn it on.

I opened up the headshell, carefully because amps terrify me , and found these issues in the pics. There is one component, what the hell it is i dont know, that is broken and some scorching on one wire.

So basically as you can realize i has no real knowledge with amps, ive built pedals on PCBs but other than that.... Any idea what is going on in this amp?

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[theAntihero]

Anyone ?

[Schlatte]

The broken thing in the first picture could be an inductor... maybe it's part of some sort of tone control? The pot + capacitor + resistor seems like some sort of tone control, right? So yeah, idk. Maybe a 2nd order filter using an inductor.
The second picture are the big electrolytic caps from the mains rectifier/power supply part of the amp maybe?

Lights up inside? Like a flash? That would mean something is discharging to the chassis/another contact somewhere. It's pretty hard to say something useful right now without knowing more about the amp, taking a look at it or at least the schematics... to search where your problems could be originating from. sorry.

[AxAxSxS]

Looks like some arcing going on there in the second pic. this would also explain the flashes of light. Fixable either by reflowing the solder at that join, or replacing the cap can if its faulty. 40 yo amp means it could use a good replacement of all electrolytic caps anyways.Not sure whats going on in the top pic. here's a schematic to a similar amp.
http://www.gjelberg.no/files/peavey_sup ... ematic.pdf

This needs attention from an amp tech. the thing the burnt looking wire is attached to is a cap can, it may or may not contain current. If you want to DIY, start by learning to discharge caps and build a discharge tool

[theAntihero]

Yeah, i think it should be looked at by an amp tech if its got lots of current running thru them, i was just trying to save us some money.

[bigchiefbc]

Yeah, you need to be crazy careful around those big electrolytic caps inside amps. They can store enough current to straight up kill you if you're not careful.

[contraterrene]

i have a f-800b, and it rules. i got it free on craigslist, because it didnt work. every single molex connector on the inside was loose or broken, but after replugging them, or resoldering, it works perfect. maybe check that a wire hasnt pulled loose from one of the connectors?
thats all ive got

watch those caps, for real. theyre friggin huge and scary.

[Iommic Pope]

Take it from a guy who has spent over six months of heartache on a sovtek: pay for the godamn tech.

[theAntihero]

Take it from a guy who has spent over six months of heartache on a sovtek: pay for the godamn tech.

Yeah i think its going to the tech, i was just trying to save me and the forumite some money

[Iommic Pope]

Yeah man, I totally understand, that was my sentiment at the start, as well.
It's a rabbit hole.