K7500 B+ (how to test)

mecha

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pardon my ignorance, but which pins on the B+ pot do you probe with the meter? I don't want to cross anything and blow it up. :)
 
Find test point 202 (TP202). You should measure approx. 130vdc there...
 
ok, as I've mentioned multiple times in a great many threads, I am no scholar on the operation of the B+. is it proper for it to read about 120.3V and then dip to 118V on very bright screens? (in this case, any fade to white screen or the lightning flashes in the Carnevil attract video)

it's worth noting that I, in my infinite wisdom, decided to attempt to scrape the big glob of glue that Wells placed on the B+ control and anything around it, thinking that I had to test at the pot itself, like an idiot, despite recalling from other threads I've read on here that there's an actual test point, and broke one of the legs off the first B+ pot, and grabbed one off a junk chassis.

I proceeded to break the glue on the new pot to get it to turn, and maybe miraculously landed it in the right spot.

mod says 130, but the troubleshooting page on WG's site has a Shutdown condition where the B+ exceeded 120V, which I ruled was not caused by the HV Shutdown pot itself breaking from the epoxy it's sealed with (cause Ken said so)

so... what next? the monitor has not exhibited any of these situations tonight after powering it on and off and running it through some heavy G2/brightness while adjusting the guns. maybe me fucking up and desoldering and resoldering everything solved the problem too.
 
mod says 130, but the troubleshooting page on WG's site has a Shutdown condition where the B+ exceeded 120V, which I ruled was not caused by the HV Shutdown pot itself breaking from the epoxy it's sealed with (cause Ken said so)


Well, I said 130 because that's what the flowchart says, but the service manual says TP202 should be 117.20vdc, so yours is fine.

I wouldn't worry about the slight difference in the voltages for very bright screens if the picture looks okay. That is usually caused by a leaky diode somewhere, but good luck finding which one...
 
seems fine now. hasn't shut off at all. mysteriously all the other games I dragged over that had various ailments are all working fine too. maybe I was right, maybe it was the damn building! ;)
 
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