"Rick Brandt" wrote in
:


One of the more common (totally dead) failures I see is a cracked
circuit board which interrupts some of the circuit traces. This is
common in the area of the flyback due to its weight. If the set is
dropped or otherwise subjected to sufficient G-forces the weight of
the flyback causes enough board flex to crack it. Sometimes these are
easy to see, sometimes finding all of them can be a real tough nut.


The set is only a few years old, and the flyback is relatively light. I
also looked at the circuit card and didn't see any marks or cracks at
all. And to be honest, I'm not sure it's the flyback. There's a
component called a High Voltage Tripler that sits between the flyback
and the CRT. When I take the tripler out of the circuit the set powers
up and goes through a short diagnostic. With the tripler in it does
nothing at all.

On the schematic the tripler is just a box, with an input, output, and
ground. If the triler is some kind of step up transformer, wouldn't the
resistance across the input and output be infinity? I measured it at a
little over a hundred ohms. Would that indicate a shorted tripler?
That's what I suspect, but I don't know exactly how the tripler is set
up. Any advice?