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previous: Peter S After doing this for 30 years you w... -- 5/29/2000 5:14 PM View Thread

Re: Bias current for EL34s in YBA-1?

5/29/2000 7:44 PM
Sean Kilback
Re: Bias current for EL34s in YBA-1?
Peter,  
 
Thanks for the frank feedback about the transformer shunt method. Next time I have the chassis open I'm going to install 1ohm cathode resistors!  
 
For my amp, I've got 480VDC on the plates of the new Svetlana EL34s. If I use your formula, that means 25W/480V * 0.5 = 26mA.  
 
So, my measured current of ~35mA is too much.  
 
Time to install an adjustable bias pot.  
 
Thanks very much!  
Sean

 
Replies:
Peter S Sean, At 480 volts you can... -- 5/29/2000 10:02 PM