Quote:
Originally Posted by Kamakiri
Only thing I'm missing is the -60V (the RCA manual says -57...close enough) on pins 1 and 5. I have zero.
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As I understand it, the -60 is developed when a sawtooth of sufficient p-p amplitude hits the 6DQ5 grid. This is called contact bias. If the oscillator is way off frequency, the amplitude of the sawtooth drops sufficiently to make the grid LESS negative. Low bias will cause HOT to conduct and plate to glow in the center, no bias lights up the plate as you are experiencing, both kill HV. If not using an oscilloscope, use the peak-peak scale on a VTVM set to AC.
Go from the hold control coil (either terminal) all the way through the wave-shaping network of caps and resistors to pin 1 of the 6DQ5, which is not plugged in for this test.
If 270 volts P-P is not found at the hold coil, the oscillator is not running. If something close is found, see where it gets stopped or attenuated.