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Thank you all for your input on this strange problem.
I did some experimenting and testing on this problem and this is what I found....
The Damper tube tested good.
The white bar does not shift at all when turning the Horz hold.
The power resistor was bad and had been replaced.
I grounded the video signal at the video amp to eliminate a picture on the screen but kept the sweep circuits working , and the white bar is goes away.
This lead me to believe the problem causing the white bar is in the video signal.
With video input connected again, I traced the problem back from the output of the video amp output tube V307 back to the output of pin 7 of the V305, the 6AL5 video detector output as shown in attached photo.
This video signal can be seen as a higher level after blanking. It seems to be causing the white bar .
I replaced the 6AL5 with another good 6AL5 and there was no change. Could this problem be before the video detector?
With video on the screen, the entire picture is shown. The white bar is superimposed over the picture. I am at a dead end and don't know where to go from here.
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