U2000 Help Please

[robsinfl]

Anyone have any suggestions or ideas? Anyone have a spare good flyback for a u2000 monitor? Part number 053X0632-001

[grantspain]

chances of having 2 bad flybacks is slim,you sure your not missing something

[sarge]

what resistor did you change to get your b+ back?  have you checked Q708 or Z702?

[robsinfl]

Sarge I replaced r104, r765, and r760 Checked q708 and z702 both test good. Chances that I am missing something is good. I just dont know what.

[castlesteve]

Ok... well I have 2 U2000's that needed repair... and I got them both up and running pretty easily.

These are VERY similar to k7400s and share many of the same parts.

I however am having the very same issue you are with a k7400 that I cannot seem to get cracked.

I too have pretty much replaced the whole board.  All of the transistors, flyback, neckboard etc etc.  Power supply works but when I connect it to the rest of the board, it just doesnt do anything.  Doesnt tick or anything.

I think my Q703 (i think) is not being properly turned on, which in turn does not turn on the small transformer which allows the current thru the H coil... and my flyback is not running. 

So somewhere either I have a real deadlock in the shutdown circuit or something.   I'll beat this thing soon... and I would bet you are having the same issue.

-s