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UPDATE, JULY 16, 2019, DAY 346
From Mike: “Hi Marshall. Well, we finished the trip yesterday. So, now back to business here.
I have been working on the convergence. The pot that I installed in the high voltage cage is not in proper range. This is no surprise since the new pot had some resistances built in to it. This required some calculations to make it come out right. One of the things that makes it tricky is the design by Westinghouse. The series resistance that makes up the resistance divider network for the pot is also the current limiting resistance for the high voltage regulator. So, the current through that network needs to be maintained in order for the high voltage regulator to work properly, and at the same time, the voltage selection by the pot needs to provide the proper range for the convergence grid in the crt. The range for the original pot was 50 megohms. The range on the new pot is roughly 22 megohms. So, I need to go back in to the high voltage cage and change some values and the work inside there is tight and tricky. But I am getting close. This work is for the center convergence only. I do not yet know what lies ahead for the edges. This has to come first.
Here we go!
Regards, Mike”
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