Peavey classic 30

[saintsfrost]

Hi guys, I'm new to the forum. Can anyone help me with my Classic 30, all of the valves light up in the back,but I have no volume.
what do you reckon? my son now tells me , that he twiddled with one of the valves and abit od=f smoke came out. If a valve has blown, would it still light up?

[52 Bill]

If a valve goes bad it may still light up or it could cause the mains fuse to blow and kill the power to the entire amp.

If your amp still turns on try plugging a spare cord into the FX loop jacks and see if the sound comes back. Be certain that the speaker is working and plugged into the amp.

[nashvillebill]

Ah, but smoke came out. Not good. Once the magic smoke comes out, it takes some technical expertise to put the smoke back in.

Time to take it to an amp repair shop. Not Guitar Center, a real amp repair shop....

[Amp Kat]

Smoke is not good as ^^^ says but do note that these tubes heaters are wired in series so if one goes they all go. It is also possible one of the fuses blew. There are 3 inside and one is the mains 3 amp 1 is the HV 500ma HT fuse and the other is 10A Ceramic heater fuse. If the fusses are good and the tubes are lighting and it still doesn't work I would have to say possibly a screen resistor has fried.

[km6xz]

Welcome to the forum Saintsfrost.
The Classic 30 is a nice little amp that is not too complicated so depending on your electronics experience and test instruments available to you, you should be able to repair it yourself.
Ask your son to help, it can be a learning experience that could spark an interest in him. Ask him exactly what he observed and in what order, because like a detective reviewing clues, any information about the failure could be a key to simplifying the troubleshooting process.
When you say "no volume" is that like "absolutely no sound from the speaker, even no faint hum when listening close to the speaker?", or reduced volume from normal? It is the former, the smoke is probably a resistor burning open so no current flows through it. That may be a cause of the no sound but it is also just a symptom of the real cause. The real cause of what made the resistor overheat needs to be found before replacing the resistor.
Do you have a digital or analog volt-ohm meter and basic hand tools available?
Here is a schematic of the amplifier: http://www.freeinfosociety.com/elect...wPmOqks7zD3-sc