Forget that negative "TV guy" assessment...this IS the best TV made.
Does this set have the black slate on top? I intercepted a trade-in like yours in 1985 and my parents used it as a daily set until 2003 or so, wanting a remote, they got a Sony 27" CRT Wega. It lived in my garage for a while but I parted it out due to the worn-out CRT (only after I rejuvenated it in '85!) and a pile-on of other issues. Had I been on VK then, I'd have kept it but I have the cabinet top yet
The low voltage regulator issue in ours was a zener diode but it took me a while to figure that out because it looked like a hum-bad capacitor. The undiagnosed intermittent vertical shrink was probably the service switch
but I was young then and kept cleaning the module pins and size/lin pots.
If you have a shorted HO Transistor, its easy to tell. Just set your multimeter on "diode test", put black probe on chassis and red on the (121-831) HOT case (the collector), it should read open but if you get the beep, its probably shorted. reversing the leads will read the damper diode, usually OK.
Never saw a fly go on these, but the "22-5001? white critical cap fails - HOT shorts" always the issues I saw. just my 2c
We'll help you fix and keep it.
Minor, inexpensive repairs will keep yours alive indefinetly!
Like Bryan said, we has parts. just find which one is bad.