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bad tube bad...

1/29/2001 6:00 PM
bad tube bad...
the other night at a show i blew a fuse and had to use someone else's amp because i had no other fuse's.  
when i got home i looked at the amp and one of the tubes was ruined. (i use el-34's) also the tube socket was burnt (from arcing i am assuming). is it still safe to replace the tube and fuse without replacing the socket? and are there any suggestions to keep this from happening again. tube type? tricks? whatever?  
1/29/2001 6:09 PM

I also forgot to add that the amp is a mesa boogie triple recto and i belive the sockets are made out of ceramic.
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1/29/2001 6:34 PM

A ceramic tube socket can sometimes be cleaned to remove any carbon deposits. If you can't clean the residue off, using a cloth, old toothbrush, maybe some solvent. If the carbon deposits don't come off, the socket will need replacing.  
What probably caused the problem was an internal tube failure.  
The socket needs to be clean, free from any conducting deposits, or you risk short circuit arcing and possibly more amp damage. Start with careful wiping with a dry cloth. Then try a dry toothbrush followed by dry cloth. After most of the soot is removed, try dampening with a non-lubricating contact cleaning solvent and scrubbing/wiping some more. Cotton swabs may be helpful down in crevices.  
If you're new at this and can't do the work yet yourself, take the amp to an experienced tech of known reputation. Someone who is authorized to do Mesa repairs is usually (but not always) a good prospect. These amps are a bit complicated and they cram a lot of stuff into a small space, which increses the servicing difficulty level, even for experienced techs.  
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