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I like to use a neon lamp to test for HV. Hold it near the horizontal output plate cap lead to see if there is HV AC there, it will glow. (just hold it near the insulation, no direct connection). If it passes this test, you can hold it very carefully near the HV rectifier plate cap to see if it glows. If there is no glow of the lamp at the Horiz. plate cap, measure the negative grid voltage at the horiz output tube. Should be around -40 to -50 volts. No negative grid voltage developed=no input signal from oscillator, or could mean output stage or damper is not operating. To help check these stages...
DISCONNECT the plate cap from the Horizontal output tube and connect the meter to the plate cap wire, not the tube (make sure it is disconnected). Then, measure the DC voltage, if you get the B+ voltage, you know it is flowing through the damper and flyback. The B+ input comes in to the horizontal output/damper system through the damper. Check if there are any fuses out in the HO tube cathode or the damper plate.
Is this the four tube model with the tripler or is it the full-tube model?
The door knob caps are generally only used in the metal tube sets where the CRT cannot provide its own filter capacitance between the inner and outer graphite coatings.
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