Millet Max Hybrid Problem
Feb 23, 2013 at 1:52 PM Thread Starter Post #1 of 5

daggerlee

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Took the amp out of storage where it had been for a couple of years. 
 
Tubes seem to be okay, both glow and voltage is stable.
 
Right MOSFET channel measures 0 mV no matter what - turn the trimpot all the way clockwise, then 10-20 turns counterclockwise, nothing, although sometimes the mV will fluctuate between 200mV - 1V, but move the trimpot anymore and it goes ack to 0.
 
Left MOSFET channel is stable and can be adjusted by the trimpot. 
 
I switched the tubes to make sure it wasn't the tubes that was causing the problem.
 
Any ideas?
 
Feb 23, 2013 at 2:39 PM Post #2 of 5

tomb

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Quote:
Took the amp out of storage where it had been for a couple of years. 
 
Tubes seem to be okay, both glow and voltage is stable.
 
Right MOSFET channel measures 0 mV no matter what - turn the trimpot all the way clockwise, then 10-20 turns counterclockwise, nothing, although sometimes the mV will fluctuate between 200mV - 1V, but move the trimpot anymore and it goes ack to 0.
 
Left MOSFET channel is stable and can be adjusted by the trimpot. 
 
I switched the tubes to make sure it wasn't the tubes that was causing the problem.
 
Any ideas?

Could be the trimmer was hanging on by a thread and came loose from taking it out of storage.  Do the tubes bias OK?  Short of some pics and a thorough inspection, I'm just guessing.
wink.gif

 
Feb 25, 2013 at 11:56 AM Post #5 of 5

daggerlee

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Now I have a new problem... there's a static hum/hiss in the left channel that's there and doesn't change with the pot. Amp sounds fine, music sounds fine... any idea? 
 
EDIT: think one of the tubes wasn't seated properly
 

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