07-01-2026, 09:43 AM
Hi morzh,
Negative bias is supplied to the 37 detector amplifier, the 37 audio amplifier, and the 42 output tubes by feeding current from the negative side of the filter capacitors to a section of the 46A resistor. The 42 output tubes have a combination of both fixed and cathode self bias. It seems to be an exotic way of doing things but you know the old saying, "any port in a storm is what to look for." It was a non intuitive problem to solve, a real head scratcher, and getting to it was less wit than luck.
LF
Negative bias is supplied to the 37 detector amplifier, the 37 audio amplifier, and the 42 output tubes by feeding current from the negative side of the filter capacitors to a section of the 46A resistor. The 42 output tubes have a combination of both fixed and cathode self bias. It seems to be an exotic way of doing things but you know the old saying, "any port in a storm is what to look for." It was a non intuitive problem to solve, a real head scratcher, and getting to it was less wit than luck.
LF
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