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While troubleshooting by substitution can be a strategy, replacing large swathes of parts can have a real risk. At some point in time you can find yourself with a set that doesn't want to work right, and unraveling layers of parts and changes can be extremely difficult.
In the end this is your set and your journey!
Always wait for the DeoxIT to evaporate and dry before you energize.
Diodes can be leaky, the horiz blanking diode CR201 would be a good part to substitute. This needs to be a fast switching diode like a ECG177.
I would take some time to look at the voltages on the Blanking Amp Q202, Vertical Blanking Amp Q217, and 3rd Video Amp Q203. The line between the collector of Q217 to the base of the Blanking Amp Q202 gives you a perfect place to scope the blanker at both the vert and horiz rates. Good waveform to look for in the SAMS. C204 and C202 are critical to horiz blanking.
Were any of the resistors in the Blanking circuit out of tolarance?
Out of curiosity does the Peak Pix control work?
Does this set have a separate focus divider?
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Beam_T
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