GE 17T026 pincushion distortion

[Down Under]

Hi guys,

I'm bringing one of these back to life and everything is now ok, except terrible pincushion distortion. It's far worse at the top (horizontal lines) bowed downwards at the centre), but all four sides are squashed inwards to some extent.

I notice that the yoke has no magnets fitted, or even areas that look like magnets should be there. B+ is where it should be and the picture is nice and bright with no blooming.

The CRT is a rebuilt tube, is it possible that there were round ferrite magnets taped to the tube that were never put back?

Any help/advice appreciated.

Cheers,

Adam

[Penthode]

If it a 110 degree deflection tube without pincushion magnets, I would expect there to be some pincushioning.

I recall fixing a similar problem on a 110 degree black and white by orienting and then sticking four short strip magnet around the tube. Trial and error is the best route. Just be sure that you don't get to close to the deflection yoke and the EHT connector.

[Down Under]

Thanks,

That's been my thoughts too. It's handy that the cabinet is aluminium, as I've been able to experiment with strong magnets on the outside as a test. I have some cheap magnets on order and I'll use a bit of double sided tape or blu tack to get the best positions before gluing them to the CRT permanently.

I was thinking that there might have still been some electrical work to do on this set, but I think that's over, it's just pincushion and cabinet work now.