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Old 03-24-2018, 10:31 PM
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Electronic M Electronic M is offline
M is for Memory
 
Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 14,758
Some progress; I got the vertical working right. The 4700pF cap on the vert osc trans had drifted in value a good bit...However, the real issue appears to be tin whiskers in the hold pot. I was briefly able to get the freq right while rotating the control, hitting it with cleaner while running and working the pot cleared the whisker.



Thanks to referman for supplying the sam's. I was able to confirm from cross-reference that one of the 'wrong value replacement' resistors were correct value in the sam's revision.

I was able to get off freq chroma osc noise in the video so the chroma section has life...I need to check the chroma stage tubes. This set has an interesting chroma section...It has the diode demodulator circuit of a porta-color, but with a crystal chroma reference osc like most other sets.
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