In article .com,
says...
this is like one of the first internal projection big screens it's got
those 3 big glass projection tubes inside., I want to check the power
supply , any better place to find the Model # ?

(1) The boys might tend less to make fun of you if you give
a complete model number (probably RK8350 and in most cases
the AK-whatever is a supurfluous detail), or chassis number
(PTV-375 for example) and symptom(s).

(2) These sets have complex power, sweep, and protection
circuits that require finesse to get working on a good day,
and without experience and a schematic your chances are
not good, even with the group's help. And while I'm at it,
some of the parts that were common failures are no longer
available.

(3) Picture quality was not that great, IMO, even when these
sets were new. Are you sure you don't want to just kick it
to the curb?