Rebuilt k7000 keeps dying, killing HOT & VR

Xyla

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Donor 2011
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Ok so I have a 19" k7000, it died, HOT was shorted.

Did full cap kit and replaced HOT. It worked for one day then died. C38 shorted, HOT shorted, VR shorted.

Flyback had white knobs, so I assumed it went bad. Replaced flyback with new one, replaced C38, HOT, VR.

It worked for a week, then while it was on for about an hour it just went dead. Fuse blown, HOT shorted, VR shorted.

What the hell? The new flyback is visually fine, so I'm not really suspecting the new flyback. Should I be? I could replace the HOT and VR again, but I think I am out of both right now, and I suspect something else is wrong.

What should I do next?
 
the replacement K7000 flybacks are some of the worst ever. they're very hit or miss. especially if you buy them from Bob Roberts, for whatever reason I've seen a majority of those fail brand new.

I had 1 white knob flyback, lifetime, ever go bad. it decided to wipe out the trace from C36 to where the red wire normally connects on the yoke. that I did wind up using a Bob kit on years ago, and I got it to work again. the biggest hurdle being I wasn't just replacing parts, I had to replace all that trace damage too.

that chassis worked fine for about a year, and then I took it out to test another one and when I put it back in, it no longer worked. back in 2011 I hadn't uncovered the mystery of the power resistors. last year I finally fixed it right, and it turned out several of those solder pads just rotted.

make sure you REPLACE the solder on all the larger resistors between the VR and where the ceramic resistors in the middle of the chassis end, and don't forget R103 by the filter cap. suck the old solder off first so you can see the integrity of the solder pads. all of these resistors get very hot, the solder joints will break down, and the solder pads can become completely detached from the board. jumper as needed.

this is pretty much where all the power runs from the diode bridge back through to the voltage regulator, so they're important.
 
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