F-50 troubleshooting

I bought an F-50 used. It came with aftermarket tubes in it; the power amp tubes say "6L6GC Made in Russia" on them. Below that one has 0506, the other has 0510. The preamp tubes say "12AX7 TUNG-SOL Made in Russia." I have only ever played it in my bedroom. I love this amp! It has been playing fine, for a couple years, until recently, when I plug in my guitar and flipped the switches on, the sound of the guitar is very faint and the distorted channel is not distorting.

I made sure everything is firmly conntected. I noticed the tubes are extremely hot to the touch, is that normal? Forgive me, I'm a newbie. Can anyone help me troubleshoot this?

Thanks,
Kevin

Okay well, now it seems to have started working again. Not sure what's going on.

you may have some tubes going. if the amp sounds like crap, is really quiet, or just completely shuts off then replace the power tubes.

Down load the manual, it has some good tips about tubes. My F30 eats tubes alive, so it is a good idea to have some backups in case something goes south.

How do I know if it's the power tubes or preamp tubes that need to be replaced? Or should they be replaced together?

payooli said:

How do I know if it's the power tubes or preamp tubes that need to be replaced? Or should they be replaced together?

Click to expand...

If the problem is with both channels it's most likely power tubes, If problem is in just one particular channel most likely pre amp tube.

Yeah, it's both channels. Thanks for the info, guys! New power tubes are ordered and on the way.

It was a bad instrument cable! The effect was like having my guitar volume knob set on 1.

(Smacking self on forehead.) But at least now I have an extra set of tubes for backup. :-/

Spares are always a good idea. Glad you solved the problem.