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RE: Still having problems with tube amplifier.

Posted by doodlebug (A) on May 17, 2009 at 15:47:01

In Reply to: Still having problems with tube amplifier. posted by Gataca on May 17, 2009 at 12:45:40:

At least you know what it isn't, which is a good thing. I don't know of your amplifier so can't comment on the details but I'm seeing some significant symptoms:

- Bias lights 'going crazy' at power up
- Have seen more 'glowing' from one tube
- Has been known to blow the B+ fuse recently
- Changing output tubes has caused no observed improvement

These tell me you've got an interstage coupling cap leaking DC onto one of the tubes. The amp needs looking at, for sure, and I wouldn't recommend you operate it until its been sorted out.

Cheers,

David

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