Westinghouse 22 inch color restoration

[roundscreen]

Originally Posted by yagosaga

Hi Steve,

the purity on the photos still looks good. There are some minor tinted spots in the corners, but IMHO they are acceptable with such a special set.

I had shadow mask troubles with the early A63-11X. One tube had a bended mask, and it was impossible to get a good purity. If the left part of the screen was clean, the right part of the screen had changed colors and so on.

The GE Porta-color crackles inside the CRT when the shadow mask is warming up.

IMHO your observed fault depends on the mounting brackets of the shadow mask inside the CRT. The CRT was not used for decades. With a rigid restraint of the shadow mask, it is not possible to get a good purity all the time. Mounting brackets and shadow mask need some compliance, otherwise the shadow mask will be tilted with warming up. IMHO the interaction of the mask and the mounting brackets is not well balanced. This could be due to the long time of quiet. I suggest tests with further operating of the tube with low beam current for 15 minutes, with normal beam current for ten minutes, and if you do not get significant results, with high current for five minutes. What are the results? Perhaps these data might more isolate the problems.

This is the procedure which I run for CRTs with bad purity.

Question to the others: is this a suitable way of testing or is there a chance of an irreparable damage of the CRT?

Kind regards,
Eckhard

I have five porta color set's and all of them make a weird metal moving noise inside the crt when the high voltage comes up. It is vary strange, But there is no problem with the purity.
Ed