Quote:
Originally Posted by bandersen
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Thanks!, Bob
Quote:
Originally Posted by bandersen
The drive control is a pot. I'll try replacing the cap and measure all the voltages and waveforms in the horizontal circuits..
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Acording to the diagram, that .25 amp fuse protects the screen grid on the 6BG6. it also supplies voltage to the horizontal drive control as well as the damper circuit. the first thing i would do is place a milliameter between the cathode of the 6BG6 & the -100 volt source that is currently connected to the cathode of the H.O.tube. power the set up & monitor the meter reading. if it is rising & starting to go over 250Ma, it is possible that the 6BG6, itself, has developed grid leakage that does not appear when it is cold. you can also sub another 6BG6 to see if it does the same thing.
about anything could be causing the fuse to blow, however the most obvious things would be the H.O.tube, the horizontal drive pot that has "whiskers" in it, the Screen resistor (r88 22k) that has lowererd it's resistance.
i would check these things first.