784-139?

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revolver1
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784-139?

Post by revolver1 » Mon Jul 17, 2017 1:48 pm

If I'm going to use a 784-139 OT with EL34 for a 68/69 JMP 1987 build is it 220k in the bias circuit?
Does anything else differ from the 100w bias circuit?

Also the droppers, is it 10k - 8.2k or is it 8.2k - 8.2k?

Thanks in advance.

RockinRocket
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Re: 784-139?

Post by RockinRocket » Mon Jul 17, 2017 6:40 pm

Schematic is your best friend. But yes 220k and 8k2/8k2 10k/10k sound right. Bias feed resistor really is only based on what the power transformer is putting out.

revolver1
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Posts: 342
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Re: 784-139?

Post by revolver1 » Tue Jul 18, 2017 1:46 am

Ok, thanks. Looks like i better do some more reasearch.

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