I have a 1980-era Mitsu VS-457RS television that has failed. There is
a red LED which lights on the front panel, but it acts as if it has no
power otherwise - There is no screen or sound.

Strangely, this happened before, but it started working again after
being left unplugged for a couple of weeks. It continued to work for
over a year.

I have done repairs on arcade monitors, so I'm comfortable with
replacing flybacks and capacitors, but I've never been inside of a big
screen. Web searches have turned up almost nothing on this model.

Any hints on where to look for info or what to expect when I crack it
opened are appreciated.