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Old 04-10-2020, 11:22 AM
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Electronic M Electronic M is offline
M is for Memory
 
Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 15,432
Then in search of a stable chroma sync point where correct tint wasn't past the end of control travel I went and and messed up the chroma!

Last night I tried to do the chroma AFC adjustment procedure in Sam's and skip the chroma bandpass buuut Sam's instructs to touch up an adjustment from the bandpass so after starting the chroma AFC (which has totally detuned the osc, and possibly cracked a slug) I went back and started bandpass last night...the chroma bandpass proceedures first step was inject on pin 2 of the bandpass amp and went well, but the next step has me stuck. The injection point and circuit for the step I'm stuck on is nutty. They want me to build some goofy hand-wound ferrite transformer resistor isolation/matching network...I obviously don't have the Motorola core part specified on hand and I don't intend to look for it, but I did try to approximate the circuit....
I can get a signal from the generator through but it is so weak the markers on low are stupid wide and tall, there's a good bit of noise on the curve thanks to cranking up the scopes sensitivity, and the first 2 adjusters don't seem to affect the curve....

This Motorola is becoming a time vampire...I put a day into it and it barely improves...I just want to get this thing done, out of the basement and move on to other things...
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