TECH HELP: K4900 Flyback Pinout

bstnguy

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Trying to ring a K4900 flyback transformer from a K4900 monitor

BUT

The schematic is different than the silkscreen on the PCB board.

Anyone know which is correct?

Thanks
 
I usually check both, but the silk screen is usually the one I go by, as it relates to the circuits...
 
Thanks for the info, I'll start there!

So, newbie Ringer question (ha!) Should a coil with a mid-tap ring okay end to end, then then mid to end?

And where are good spots to test the primary coil in circuit? (for future testing)

Thanks again!
 
I've sometimes had issues with going from what is silkscreened as the tab to the end, but the flyback worked fine.

If I have a question about a reading, I'll grab a chassis I know works and compare readings.

This might be a good project for my content-starved website - ring tester readings of functioning flybacks for repair comparisons....
 
Exactly what I tried, but the only other 4900 I had has a broken flyback.

I ordered a new one, so I'll compare and post what I find.

Flybacks tested the same.

130V rail was measuring 160V, 6.8K ceramic resistor ohmed out good, Q351 tested good, swapped IC301 and BAM!!!!!

WORKS!!!!

:)
 
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