I got this set in for repair and noticed a high pitched sound when
turn on is attempted.. The heat sink near the flyback has two
transistors mounted to it. The larger one that looks like it could be
a Hor output is marked J6020. I checked it as though it was a hor
output and it looks shorted all around. I can't find any information
on what type of device this is. The board is marked near it "HC401".
So I'm assuming that is its designation but I really am not sure. The
front of the other three terminal device on the heat sink is covered
by what looks like an HV cap so I was not able to get a number off
that but it looks to be a little small to be a hor output. Has anyone
seen one of these sets with this symptom who might be able to offer
any assistance? And if by chance anyone has a schematic they would be
willing to share that would also be greatly appreciated. Thanks, Lenny.