Westinghouse 22 inch color restoration

[roundscreen]

I have seen set's that the purity will go out when the contrast is set to high or on a bright white screen at normal settings.
Someone told me the electrons where hitting the shadow mask with a lot of force and it was moving the mask enough to mess up the purity.
Double check the high voltage and the crt screen settings. Then try turning down the contrast to a point where you can just see the red and see if the problem goes away.
Still that is one cool set you have and I hope you find the problem.
Ed