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previous: Matt At this point, if anyone can tell m... -- 1144780635 View Thread

Re: Hum/noise problem

4/11/2006 6:32 PM
Re: Hum/noise problem
Sure, it is NOT anything after a control that can turn it off.  
Pull V1. If that shuts it up, then the V1 circuit or the tube itself is at fault. if not, then the trouble is after V1.  
That you could shunt the plate of V1 and kill most of the hum says it is coming in there. Ground the grid hard to ground with a clip lead. if that solves it, then the wiring and input jack is suspect.  
Basically you move backwards through the amp killing the hum until you get to a point where you no longer kill it. At that point you just passed the problem.  
By the way, WHICH plate did you ground, the first or second stage? If you plug into thet low gain channel, is the hum still there? Or is it only on the high gain input?

Matt Thanks again.Enzo, ... -- 4/12/2006 6:07 AM