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Have been reading your interesting comments on the peaking coils. Working on the peaking coils tonight: the two 1mH coils in the I channel. A previous repair replacement for one was 400uH and the other was open and unfixable. The 6.7mH and 1.9mH peaking coils have been installed in the Q channel.
Have been doing some further power up tests (with scope and multimeter). Found an AGC fault: picture overload and inability to adjust with AGC control. Found two resistors at V17 AGC Keyer 4.7M and 2.2M at the control had drifted upward. RCA notes said later chassis's substituted 3.3M for the 4.7M. Replacements made and now can set AGC to the point sync starts to clip.
Getting good horizontal and vertical sync and traced good luma to first Video amplifier.
Ballast Resistor maximum temperature after an hour run reached and sat at 75 degrees Celsius. Happy with this as the temperature is close to my target max and the heat is properly deflected away.
After the peaking coils with the chassis essentially complete will next focus on constructing the jig to inject the IF alignment generator to the tuner. RCA obliged with the details and I have my fabricating tools ready.
Still a few weeks away from testing the I and Q channel response and look forward to comparing results.
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