1980 Sears (Sanyo) 25" Console TV CRT Problem

[Eric H]

Here's my guess as to what happened.

When you tuned it on without the CRT plugged in it charged up the High Voltage, when you plugged the board back in it probably discharged through the grounds on the board.

At some point you cracked the CRT, maybe when removing the tester socket or when you plugged the CRT socket back in.

Plugging it in with air in the CRT allowed High Voltage to jump to the Guns and from there to the Video Board, possibly damaging it.

What I see in your video could be a Ground left off the CRT somewhere, perhaps the strap or spring across the bell of the tube, I have seen new CRT's snap and pop on first start up before.

I would disconnect the High Voltage lead from the bell of the tube and stick the end of it in a Glass Jar and put it somewhere away from the chassi or ground (and away from you), then I would turn the set on and see if it will run as far as sound and the heaters on the CRT lighting up.
If you have a High Voltage Probe you could check and see if it has High Voltage.

If it blows a fuse at this point then you know something is wrong, if it doesent you could plug the CRT back in and try it, double check all the grounds on the CRT and the chassis.