CTX PL7 Monitor
 

The monitor is a 17" CTX PL7. I believe it has a 1769-J21 Chassis.

I was using the monitor when it's brightness begun increasing in steps at 1
second intervals. After a few intervals, I shut the monitor off as the
image was very bright. When I turned the monitor back on, the screen was
very bright and out of focus, after 5 - 10 seconds the horizontal deflection
failed leaving a single vertical line. Since I have been testing the
monitor, the problem has become worse, now after 5 - 10 seconds, the high
voltage shuts down.

The voltages off the switching transformer are steady at 72,
35, -35, -47, -6.7 and -14.5 VDC.
The voltage at the base of the HOT is steady 1VDC however at the collector
of the HOT the voltage rises steadily from 20VDC to ~115VDC. When the
voltage reaches 115V, the high voltage shuts down and the collector voltage
immediately drops to ~85 volts and continues to drop. While the collector
voltage is increasing, a few bright, focused, slightly diagonal, horizontal
lines appear in the lower section of the screen.

I traced the path from the collector of the Hot to the flyback, then ohmed
out the pins until I found a set that measured .6 ohms. The voltage at this
pin measured a steady 72 volts.

Unfortuently, I do not have a scope to check any signals.

Thanks,
Nate

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