Toshiba 42HP66 flickering

[deh4170]

Hello and thanks in advance for all help:

I have a Toshiba 42HP66 that is flickering and pixelation is all over the place. Sound is great and I have not had the "pop" of death that many have discussed nor have any of the fuses blown. The question I have is this - the panel is a PDP42X3 and shows that voltages should be: Va = 60V, Vs = 188V, and Vy = -190. I have checked all the power inputs and everything leaving the power control board is correct (I did make micro adjustment to bring the Va and Vs dead on target). On the Y sus board at the Vy test point (R36) the reading from power up bounces from -197 to as much as -230. Does the bouncing voltage point solely to the Y sus board or could this be something else? I have attached a picture of what the screen looks like. Thanks again.

[m4malious]

Re: Toshiba 42HP66 flickering

Hi,
Did you ever get an answer on this?

I have the same issue - Vsc and -Vy on the Y-sus board jump all over the place. The guide says they are static DC voltages of 125 and -200 but a circuit reference talks about "floating grounds", so I'm not so sure.

M

[drpj23]

Re: Toshiba 42HP66 flickering

You probably are looking at repairing the Y-sus.
The floating ground is using the sustain boards ground rather than chassis ground but it should still be static I would think.
I would put pictures up and wait for ones like budm or tom66 to help you.

[tom66]

Re: Toshiba 42HP66 flickering

Floating ground is variable on this model (it's typically the same as the sustain output), but the final sus waveform is measured relative to the chassis ground.