GE13PF6504 no picture but green splotches

[technoman9]

Zeno, John: Thank you for the kind words, it's a pleasure learning from you! I studied electrical engineering a decade ago but since have gone into a software/systems engineering career and thus rarely handle circuit design or repair. However, I often troubleshoot these software systems and so am good with following instruction and using tools to figure things out, though with CRT TVs I'm still learning the "system" if you will. It can be stressful learning electronic repair by one's self when one doesn't have any mentors to teach by example, so I'm grateful to have your patient guidance here.

Zeno: do you mean diode D803 in the power supply image, or the diode seen in the middle of the flyback transformer image, D441? Do you suggest replacement because of common failure or preemptive concern?

I checked those capacitors as you two suggested and indeed found C443 4.7 uF to be open. C437 checked out good but I will get new ones of both anyhow. I will be inspecting the rest of the electrolytics on this board to see if any others have gone bad. Thanks for the explanation about the capacitors' use. I absolutely love learning the "why" behind circuit design choices and possible failure modes.

I'm going to order the NTE replacement for the regulator unless you suggest otherwise: https://www.ntepartsdirect.com/ENG/PRODUCT/NTE15018 NTE seems to be trustworthy and I can order directly from them. The specs match the STR3115 perfectly.