Philips 9607 geometry problem

Hi folks, newbie here.

I have just bought a used Philips 36PW9607 and it looks good, apart from a terrible geometry problem.

Some of the time the picture looks ok, and all lines are straight. However, at other times, with certain broadcasts the picture distorts in the same way old CRT computer monitors do. The set displays terrible pincushion, pin-balance, trapeziod and parallelogram effects. These change dramatically and dynamically with different source material but mostly seem to be affected by bright backgrounds or text. It doesn't matter which aspect mode the screen is set to, except that it is more obvious where there is a gap around the displayed area, ie: 4:3, 14:9, etc. Viewing via standard RF signal or Sky digital also makes no difference, other than when displaying the Sky program "info" which just exaggerates the problem.

Is this fixable, or have I bought a dud?

Thanks for any advice.

Mike.

[hamster]

It sounds like EHT ballooning. Obviously it depends on how severe it is, but Philips tended to use cheapish EHT stages and got quite a lot - My Philips 29" certainly does more than I'd like.

The bright content pulls the EHT voltage down, and thus the electrons move slower, so the picture gets larger in the bright area.

Not much you can do. I suppose you can swap the flyback transformer, but getting one at a sensible price might not be easy.

Hi,

Originally Posted by hamster

...so the picture gets larger in the bright area.

That's exactly what happens and it is most severe once the set has fully warmed up, it seems to be less severe when it is cold. Looks like I'll have to sell it then, a pity as the picture is very good in all other respects.

However, I have just found a Tosh 36ZP46 so all is not lost, yet.

Mike.