Peavey Classic 100 series no sound

[Crazyhorse5]

Hi Im new at messing with tube amps. I have a Peavey amp I believe is called a Classic 100 series 50 watt 2x12.  The amp produces no sound. The pilot flashes as you power it up then goes out the tubes glow but the pilot light is out.  Take the tubes out the pilot lights up.  Put new tubes in same result.  Dim bulb tested with tubes in bright then fades to dim.  Tubes out dim bulb test same result.  The guy I got it from said the fuse would keep blowing it would play then in a few minutes pop the fuse.  They put in a 20 amp fuse in a 3 amp socket then it had no sound.  Any ideas where to start?  Amp made in around 1975 and is a Hybrid.

[smackoj]

hi horse; <any ideas where to start?>  1. find a schematic for it. 2. get the proper fuse and install. 3. make a diy current limiter before you attempt to turn it on again. I think there is a thread in the Tech Tips Archives about building an inexpensive current limiter.

If I had to make a first guess, based on your statement about people running it with such a big fuse in it, I would definitely search for some failure in the power supply. And BE CAREFUL cuz these tube amps, and especially the hybrid types running tubes in the output, use REALLY high voltages!!!!!

 

[Crazyhorse5]

Yes thank you for the response.  Speakers work and the wire and plug for the speakers work.  Does anyone happen to have a schematic for this particular amp?

[smackoj]

check the peavey website (sometimes an email to their 'tech support' office will yield a scheme) or search for a forum that has Peavey VT group, they should have it.

good luck

 

[plexi50]

Your going to have to do a lot of eye ball tracing and get to know the amps circuit. Where the preamp driver transistors are that link to the power coupling section,bias and so forth. It's not going to be fun. And your going to also have dougs listening device. You can build one easy.

[Jack1962]

1st look at the plate on the back or the bottom of the amp it has the model # and the serial # on it then call peavey contact the parts department they will email you the schematic. 2nd remove that 20 amp fuse it should be a 4 to 7 amp fuse. 3rd take a look at it can you see anything burnt , I bet you can.