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It worked for about 10min, then the horiz shrunk a little, then lost sync. The problem was just a horiz osc tube. But strangely, the tube tests ok (just a little weak), I would have not expected it to cause problems. I going to keep this tube, and when I get the next Motorola going, try it in the horizontal and see if it has the same effect. If I swap it with the vertical oscillator tube in this set it works fine in that circuit.
Also when I took the chassis out to see what the problem was this time, I didn't want to pull the 7JP4 out of the cabinet, so I used that one I said was really weak. But sometimes now I turn it on and it comes up ok (not as bright as the other one, but watchable with the lights on), but sometimes it looks very weak. Nothing I do seems to change that after it's powered up, but if I turn it off and on again sometimes it comes up bright, sometimes not. What's going on? The base doesn't appear to be loose. The other 7JP4 always comes up bright, so this must be something with this tube, and not the set.
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