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previous: Zoltan I like using the shunt method becau... -- 4/4/1997 12:05 AM View Thread

Re: is the shunt method dangerous

4/6/1997 1:05 PM
Andy Ruhl
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Re: is the shunt method dangerous
I think the shunt message is being confused here in the original post. The transformer shunt method is when you shunt the meter across the output transformer, from one leg to the center. Set your DVM to milliamps, and you're set. EL34's like to see about 40 ma, usually. Another method, the cathode resistor method, is a good one. You need to install a 1 ohm (exactly one ohm) resistor to the cathodes of the power tubes. To make a long story short, by reading the voltage in millivolts across the resistor by ohm's law is the same as plate current. And there are no voltages in the range of 500 to scare you! You can't install these resistors in every amp, though, only do it in one you plan to keep and mess with a lot. The transformer shunt method is best for general bias setting, but you have to be careful, you can really do some damage if you slip off the socket! Andy

 
Replies:
j krogh the impression that i had of the ca... -- 4/6/1997 9:51 PM