10-25-2013, 08:37 PM
It is very unlikely that the voice coil wires have anything to do with the power supply problem. The voice coil is isolated by the output transformer, and grounding of the wires to the frame, or chassis for that matter should make no difference.
As far as Brenda's question, a lot depends on what is actually wrong with the .05 cap. It is connected from the B+ line to ground, yet it did not show a short or significant resistance when the rectifier filament pins were checked to ground with an ohmmeter. This cap should just be an RF bypass, and the set seems to work without it, so it really is a mystery. Possibly the cap breaks down and arcs internally when the voltage reaches some critical level?
We really are not sure if the cap is actually at fault, so you might connect the cap back temporarily and turn up the variac just enough to see if the filter cap gets warm at all. That would confirm it once and for all that the .05 cap was the problem.
As far as Brenda's question, a lot depends on what is actually wrong with the .05 cap. It is connected from the B+ line to ground, yet it did not show a short or significant resistance when the rectifier filament pins were checked to ground with an ohmmeter. This cap should just be an RF bypass, and the set seems to work without it, so it really is a mystery. Possibly the cap breaks down and arcs internally when the voltage reaches some critical level?
We really are not sure if the cap is actually at fault, so you might connect the cap back temporarily and turn up the variac just enough to see if the filter cap gets warm at all. That would confirm it once and for all that the .05 cap was the problem.
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