This is actually a method of calculating plate dissipation in watts of a Cathode biased amp by using just a voltmeter, not how to bias as the title suggests.
The subject of much discussion, argument and disagreement, found on a TDPRI forum but the basics are 'basically' correct if you need to figure out the plate / anode dissipation in a cathode biased amp!
The blue text below is exactly as posted on the forum.
The text in red is the figures I have inserted as taken from a typical
Watkins Dominator Reissue, manufactured by Amp-Fix running EL84/6p14p output valves/tubes x 2
Charlie Watkins rated his Dominator at 17 watts and from the calculations below, he wasn't far out.
Sometime in the future, I'll compare these figures with an output test using a signal generator, a scope and a dummy load,
which I have done many times, and from memory I would say barely just 16 watts.
What ever is said on a forum, right or wrong someone will always know better and challenge it. There are rarely any winners and no one's any the wiser at the end of it all, which is why I don't involve myself with any forums. I have used the knowledge I have gained from mistakes and many years of experience in the electronics trade and it has "usually" served me well. You can see from my contradiction of the title of this subject that I'm probably just as bad, but it was basically the title this poor chap got wrong rather than what he was trying to explain.
If you don't agree with me, that's absolutely fine, I'm sure you are right!
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