Biasing Sovtek Mig-100

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martin manning
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Re: Biasing Sovtek Mig-100

Post by martin manning »

From what I posted above: target Vcta = (0.7 x Pa Max x Rcta)/Va, so for two tubes you get

(70% x 60W x 37R)/545V = 2.85V

The tubes aren't perfectly matched, so they will draw slightly different current at the same Va and Vg1. Split the difference or set the highest one at 70%. Don't forget to recheck the plate voltage to see if it moved.
RJSkypala
Posts: 14
Joined: Sun Nov 25, 2012 5:41 pm
Location: Philadelphia, PA

Re: Biasing Sovtek Mig-100

Post by RJSkypala »

Thanks everyone. Put in a new set of SED 6L6GC's and got the bias squared away. I am very confident at biasing now! Also, I never remember the amp sounding so good!

Now onto getting the parts for my 5E3. Thinking of picking up a boothill amp kit and classictone transformers. JJ and EH tubes at first then play with some more expensive stuff once I get it working.

Any advice on parts or suppliers? It looks like the boothill kits have quality stuff in them.
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