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previous: Jack Collins I bought a non-functional crate blu... -- 3/12/2003 5:06 AM View Thread

Re: Crate Blue Voodoo bias???

3/12/2003 5:36 AM
Enzo
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Re: Crate Blue Voodoo bias???
It is just an amp, and really they are all the same under the skin. Pretend it is a Bassman.  
 
WHat did the bias voltage read. Current isn't everything. Too much bias voltage and there will be darn little curent.  
 
How about the screens - got voltage on em? No open resistors.  
 
What form bias on this one? Cathodes grounded? Or cathode biased? Make sure they ARE grounded, or verify they are lifted to the bias voltage.  
 
Try divide and conquer - send and input signal at the effects loop or power amp in jacks.  
 
Check pin 1 and 6 of each preamp tube. There better be high voltage there or there is a shorted tube or an open plate load resistor. Or you are missing some of your B+. Now check pins 3 and 8 of each preamp tube. 0 volts means tube not conducting. Ther should be a volt of two at each cathode unless ir is a cathode follower in which case it will be substantially higher. No zeros.

 
Replies:
Tim I Have worked on these before but n... -- 3/13/2003 3:21 AM