K7000 - rebuilt - turn on - click - nothing...

modessitt

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I've got two chassis here (25" versions) that have been completely rebuilt. When you turn them on, you hear a "click" from the area of the flyback - or maybe the pincushion transformer?) and nothing. B+ jumps right to 160.

I've replaced everything - flyback, caps, HOT, VR, IC3, IC2, IC1, T2, C36, C38, almost all the power resistors, different transistors and diodes, etc. Reflowed and jumpered just about everything even a tiny bit suspicious. Nothing.

I gave up on one chassis and transferred all the new parts to another chassis and it worked just fine. Now I have another chassis doing it. It's pissing me off...
 
i have seen a couple that R103 was open or to far out of spec and caused similar problems like that.

also jumper the + lead of C23 to the jumper on the opposite side of IC2.

i have seen this cause your issues as well.

Peace
Buffett
 
i had a 27" Neotech that i replaced the flyback on (it was working but drifted in and out of focus.) after putting it all back together i had pretty much the same thing, a bit of noise but no neck glow. looked everything over and eventually noticed that i must have bumped the remote board on something at some point and busted one of the adjustment pots. made up a replacement from a scrap K4900 chassis and suddenly it all worked just fine.

i've also broken a pot or two when doing other repairs on monitors; a lot of them are old and were fragile even when new.

just something to make sure you check.
 
I may swap R103 as it was hot and measuring funny while hot but then measured normal when cooled and pulled.

Will also check the other...
 
When I did mine it popped the 2 fuses, the main fuse and the secondary. I put two caps in backwards, the main filter cap and the one near the voltage regulator, right below the primary filter cap. Then it was upside down and backwards, putting the yoke wires on, as labeled on the pcb caused this. Changed the wires around fixed this. Now I have to fix/adjust the width coil. Any ideas on where to get a tool to do this? I was thinking of using a cut piece of hex wrench and wood stick or glue to a plastic straw and adjust with power off. If there is a tool for this I would like to know where to get it.

P.S.

You will not see me here much more (monitor section) I really really hate these things and will not mess with one EVER AGAIN after I get this one going again.
 
When I did mine it popped the 2 fuses, the main fuse and the secondary. I put two caps in backwards, the main filter cap and the one near the voltage regulator, right below the primary filter cap. Then it was upside down and backwards, putting the yoke wires on, as labeled on the pcb caused this. Changed the wires around fixed this. Now I have to fix/adjust the width coil. Any ideas on where to get a tool to do this? I was thinking of using a cut piece of hex wrench and wood stick or glue to a plastic straw and adjust with power off. If there is a tool for this I would like to know where to get it.

P.S.

You will not see me here much more (monitor section) I really really hate these things and will not mess with one EVER AGAIN after I get this one going again.

I've honestly just used an allen wrench. while it was off, of course. your results may vary, but I was able to get the adjustment right within like 2 or 3 power cycles lol.

the kind you're supposed to use though is made out of plastic. why a metal allen wrench is no good because it gets too hot and one of those plastic jobs is just fine is beyond me though.
 
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