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Since I have a very another tube chassis zenith (20yc130) which is nearly the same, I decided to scope the video signal at the video amp transistor collector and the grid of the video output tube. Just to see how it should look when there is a signal. I prob should have check the videok cathode follower (6KT8) but its getting late so need ot knock off and resume tomorrow.
I also checked the agc on the working zenith so see how much hash is ok on the AGC line. Should be very little and it was. This set (the 20x, not the 20y) is VERY sensitive on the AGC setting from blank to loss of sync in only a few degrees of rotaion of the pot. I have a feeling the AGC is still not right. I dont think it should be that critical.
there are a couple 6KT8's so I wil be checking subing etc... the other is for the syn amp.
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