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I replaced the crispy looking capacitor, as well as an inch or so of wire that was cooked from being too close to the power resistors. Lacking a test jig, I lugged the thing up to the cabinet and hooked it back up to everything. Plugged it in... nothing. Tube light, it's not drawing too much current, but no sound and no picture.
So, I lugged it back to the bench to do some voltage checks, I pulled the horizontal tube, propped it up on it's back on some scraps of wood, hooked it up to the bench speaker, and plugged it into the isolation transformer. Tubes light up, start checking voltages. No B+. No high voltage of any sort. Nothing coming off the rectifier diodes. Huh? I unplugged it and traced wiring. The HV lead of the power transformer runs to the circuit breaker... check it, good, goes to the degauss coil plug... wait. Degauss coil! I never plugged it in. I searched the chassis for the degauss thermistor indicated on the schematic. Nothing. Ran back upstairs - guess what? The deguass thermistor and limiting resistor are on the degaussing coil frame. And without that... no HV. So, I bypassed the degauss coil connector with a substitute component with the approximate hot value of a termistor (a clip lead). Fire it up... I have sound! TV static comes in on the speaker... followed by sparking from underneath the damper socket. There is some signifigant arcing coming from a terminal strip. Closer inspection reveals the defective component - the terminal strip itself. This is a small terminal strip, and it carries high voltage, with a couple of large rated (4kv and 1kv) ceramic caps on it. It has carbonized along it's length from a high voltage terminal to the grounding lug in the center.
The caps connected to it look pretty crummy from the sparking this has been putting off, and there is a burnt mark on the metal chassis just above it - hidden by a big resistor.
So, I'm going to stop by my local electronic parts store tomorrow, and see about getting a couple replacement caps, and see if I can get a new terminal strip. I have a handfull of used/salvaged ones. But I'd like to use a new one in this particular application.
Anyone ever seen this before?
-Ian
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