F-50 Cutting Out

[marsnightlife]

I've had an F-50 that I got used for about 7 months, and it's worked fine up until about a month ago. I turn it on and it runs fine, but if I play it above a certain volume for a few minutes the sound just cuts out completely.

I replaced the power tubes and the fuse the first time it happened because they were running hot. Everything seems fine except for the fact that it stops playing after a few minutes.

I also tried replacing V1, but the new tube seemed to have a whole bunch of microphonics in the clean channel.


Anybody encountered this before? I haven't been able to get a hold of the local certified repair center yet; he hasn't been at work whenever I've called.

 

[NDRU]

What kind of tubes did you put in it?

I mistakenly put some non-mesa tubes in my F-30 and they weren't the right rating. They burned too hot and I lost sound after a while because of the tube red-plating.