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After reading more of the repairfaq site, I really have my fingers crossed that John Folsom's contact can do something. The chances seem to be slim, though. The site points out that the windings are extremely fine (often #40 or so, very delicate) and need to be wound in many layers. (I think it mentioned mylar tape, but to meet UL, the tape has to be fire retardant, like Nomex.) It also says that people who worked at a TV manufacturer reproted they had one guy who did the design. I want to verify that from my experiences at Motorola and Zenith. AND, the guy who did the design was not the same guy who wound the transformers, which took a very meticulous coil expert in itself. An additional problem with flybacks is that the secondary is self-resonant due to the distributed capacitance, and this must be correct - this means that the flyback design cannot be tested until the whole thing is potted in the intended manner. Trying to figure out what this resonance wsa supposed to be from a burned out example seems difficult too.
The best practice was to run the prototype through the production potting line so the prtotype potting is made to the same composition and thickness as will be used in production. The designer measures the result, and orders a new prototype with adjusted winding parameters (number of layers and turns per layer, wire size, etc.), and they try it over again until they get it right. I manged to apprentice to the point of designing the flyback for a small black and white set by starting from a known design and modifying it a bit at a time. Starting from complete scratch would require making a series of test windings to calibrate your process.
One of the innovations that saved a temendous amount of time was concocting a mixture of different grades of silicone liquid that would mimic the final solid silicone potting. The the flyback prototype could just be wound and tested while resting in a bath of fluid, so the turnaround time was reduced. A final test of a properly potted one was still needed to verify the design.
Another aspect of design is that the potting compound must contain fire retardant for a product to meet UL. However, the fire retardant degrades the dielectric characteristics of the potting compound, so it is necessary to carefully adjust the formulation - too much fire retardant will actually cause overheating.
So, John, good luck! My opinion: it just may be possible to tackle this, but it's not simple, and the time will have to be donated or you couldn't afford it.
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