I have acquired an Alpha 76PA with 3 8874 tubes. I get 1500 watts output with
75 watts drive but the plate idling current in the SSB position is almost 400
mA. At 1500 watts out, the meter is against the pin! Grid current is around 75
mA.
Doing some searching on Google, I see the solution to the plate current meter
indicating high plate current is to put a plate current doubler on the meter.
Why not just fix the circuit? Why does the meter read so high? Bad design? Bad
component? I really dislike fixing the symptom.. I would rather fix the
problem.
I have run a spot check on the metering resistors and they seem to measure ok.
Has anyone actually fixed the plate current metering circuit?
Thanks
73
Jim W7RY
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