Help! My ODS suddenly quits working, then orks again..

[Tdale]

I had a guy over today, and he was planning to buy my hybrid-a. It has always worked perfectly since the day I finished it, and indured a two and a half hour gig at high volume recently.

The only thing I've changed since then is that I replaced the 470 ohm screen grid resistors with 1.5k resistors. I also added a stereo jack for a standard foot switch, which I connected via the 5 pin xlr that was already there.

What happened was this:

The guy started playing at moderate/high volume for a while. Then suddenly there was a kind of a cracking sound, and the amp went quiet. Not dead quiet, there was still a slight hum, the hum that's always present, but no signal from the guitar.

I wrigled the peramp tube a little, and it made horrible, crackling and buzzing sounds. I removed it, and put in a new tube. Everything worked fine for about 5 minutes, then the same thing happened again. When I touched the tube, it made the same noises. I removed the tube, and put it back in again (didn't have more preamp tubes) and the amp worked fine again! 5 minutes later it happened all over again.

At this point the guy didn't really want to pay me money and bring the amp with him....

Any ideas about what's happening? Could it be a bad solder, or something in the pramp socket that short circuits?

Any tips are appreciated!

Tommy

[CaseyJones]

I'm thinkin' two things.

One, you're probably on the right track with the bad solder joint. Get in there with a soldering iron and re-heat anything that's connected to that socket. Which brings us to:

Two, if you have junk Chinese sockets in there I have no sympathy for you. Don't bother re-heating solder joints if the socket is garbage anyway. Take a deep breath, unsolder it and replace it with something better.

[Tdale]

I got the second from the top:

http://www.hoffmanamps.com/MyStore/perl ... =596950072

Not sure if I got them at Hoffman, but It's the "plastic" type with the shield base crimped to the socket.

Exactely what kind of socket do you recommend? I had to change a socket on another amp once...maybe I got bad sockets. Point me in the right direction, and I'll buy the socket no matter what they cost!

Tommy