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I need to replace the flyback transformer on my Atari SC1224 CRT monitor. The flyback I removed from this monitor has a model number of Kf4825G, and has an RC snubber attached to it, which does not seem to be easily removable. The high voltage cable goes through this to the CRT. Here is a picture of the bad flyback: Kf 4825G Flyback Transformer

The only replacement flyback I've found, which according to the eBay listing it's a replacement Kf4825G flybacks, does not come with the RC snubber. This is the eBay listing for it. And here's a picture of it: Replacement Flyback

Is it possible that with this replacement flyback, the RC snubber is not needed? Or, should I attach the existing RC snubber to the new flyback? It does not seem to be easily disconnected from the flyback. Looks like I would have to cut the thick red HV cable? (I don't think that's a good idea)

I already messaged the seller asking this, but he has no idea.

Here is the Service Manual, if anybody wants to see it.

Thanks for your help.

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You are probably going to need a snubber to prevent the ringing from damaging the transistor driving the transformer. If you have access to the transistor then you can measure the ringing and determine whether or not it exceeds the rated voltage but this might damage the transistor in the process.

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Snubbers are (from experience) always necessary because they dampen first few oscillations in flyback operation (see here). Flybacks inherently experience these oscillations because of their contruction (Windings form a transformer, thus feedback force is met when primary side switches off). However, snubber is always custom made for each flyback type. This can get tricky if your replacement flyback is not 1-1 replacement. Construction details can be found here and also Power Electronics (from Ned Mohan) has a section on it (see here table of contents). However, always test this "in drydock" ´stead of trying to test it in device. Beware of high voltage and high current sparks!

Stay safe and use "your nuddle"...

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