"The outside core is accessible, and there is a nice gap between it and the potted windings. "

It can be a chance getting the polarity right when you buck/boost, but with a fly (LOPT) like that it is easy to see on the scope. I wanted to buck the pulse to the yoke on this little 13" Sony I watch sometimes, I didn't buck the top end where the 1,000 volt pulse is, I bucked the bottom. Makes more sense.

"Both 13 & 19" used 120VDC as their B+. The 19" regulator was simply
higher current. "

Makes sense by backward reasoning. Shutdown is the same, there is a law or something that it must when the radiation hits a certain level and that is that. Thus, a unit with more nominal B+ will have a higher OV shutdown threshold.

"Capacitance of 6,000pf did work..."

It is possible it is perfect. For market share in the repair parts market they do occlude the fact that some of these parts are the same. Your average tech has no way of telling even with the best of equipment. And teachers can't teach what they do not know. they offered me a job, well one guy who worked at Case University. he said they can't find anyone to teach what I taught him to get the job there, and that was very basic. the traveling turned me off but I might take it now, however they must take me with absolutely zero accreditation, official anyway.

"I still have to
track down an original flyback driven 13" monitor to make sure the other voltages (with the 6Kpf cap) are within reasonable limits"

There appears to only be one scan derived source, 12 volts. They do not change the number of turns on one winding of a transformer for different screen sizes. It is almost for sure well within specs. think about it from the engineers' point of view.;

"That is what we do at my shop! "

Good. would you like some references to some music ? Judas Priest - Another Thing Comin', Queensryche - Best Man, there are more. I odn't give up. Well as a rule, sometimes I see no way to get er done and then I pull out faster than a (insert your own thaing here)

"Thanks for all your technical advice, that has clarified the schematic a lot for me, obviously you have experience with either designing or repairing monitors/TVs. "

Not designing so much, but I have made alot of money making things work that nobody else could. Part not available ? They called me. I was good. We had a bunch of countdown chips that were bad out of the box. No sync. With the addition of a generic PNP transistor I fixed it and the sets ran fine on the defective IC. I have modified more power supplies than they have designed. when I put a winding on a fly (LOPT) to isolate the filament of a CRT with an HK short I used a resistor of like 5K to make sure it was effectively shorted and not intermittent (which many were) and then boosted the high frequency response of the video amp to compensate for the stray capacitance introduced by the video being imposed on the line.

At one time, I considered a big shop. I have been in business but it only got to 2 locations and we got sick of it. But I considered a test for tech applicants. One of the first requirements is to be able to draw a block diagram of a color TV. And I don't mean 3 blocks, I mean with some detail.

From your posts I am pretty sure you can, but how many can ? Or could ? So many places had incompetent people it left a bad taste in the customers. Where I worked we were cheaper and better because we were more efficient, and ALSO MADE MORE MONEY. Competence pays off if you know how to use it.