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I have seen the hot melt glue on the diodes do funny stuff to them. I like to scrape it off. I have seen some of those diodes short.
Another possibility is the power supply switching transistor may be shorted. If it is, you need to replace the power supply control IC, the transistor, a diode or two, and the electrolytics in the power supply; especially a 15/50 and 2.2/100 next to the IC. I replace those on EVERY CTC169 I work on. Iv'e seen a lot of those power supplies go *POOF* because a 25 cent cap fails. The horizontal output may be bad too, if the supply started running away. If the B+ goes up from the usual 140VDC the high voltage goes up too. Sometimes that killls the HOT, but the flyback survives. Check the big 15 watt resistor near the AC input. 2.2 ohm, I think. I've seen those open at the same time as the fuse, and even INSTEAD of the fuse.
I figured out how to use italics and BOLD. Cool!
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