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High voltage - is it a problem?

2/19/2001 1:06 AM
Jaunt
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High voltage - is it a problem?
i have an old Jansen (New Zealand company) Bassman 50 head which i'm restoring.  
 
 
 
the circuit is very similar to a 6g6 bassman, but both channels are 'normal' and the PI is a cathode following version of the fender deluxe one (taps from both plate and cathode)  
 
 
 
i've measured the voltage from ground to plate, and it reads 499V. screen voltage is 370V. this seems a bit high for 6L6s - i read somewhere that old valves could handle it but new ones would die pretty quickly?  
 
 
 
is this actually okay, or should i look at drilling new holes and putting in a valve rectifier? this is my first project so it'd be nice not to have to do anything that drastic to it.  
 
 
 
i've put 1ohm resistors in the cathode leads, but am only reading 10mV across each (ie. 10mA). the original bias supply was non-adjustable, so i've changed it to a regular bassman one. what should i get across these resistors? 40-50mV?  
 
 
 
any help appreciated!  
 
 
 
:) darren

 
Replies:
Don Symes Check cathode-to-plate voltage - th... -- 2/19/2001 1:32 AM
Cliff G'day.I have a Jansen Bass ... -- 2/23/2001 12:20 PM