Low HV on K4600

Riptor

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I have a 4600 thats only getting about 12k at the anode. The monitor is working but the picture is really small. The B+ appears to be good at around 130vdc. The chassis has been recapped and I have checked everything I can think of. I even swapped out the flyback and filter cap as a last resort. Regulator transistor was swapped with a known good one. I swapped the HOT from a parts chassis but it was untested. It appears to be ok and was not shorted, as was the original on the monitor.
Any ideas here?
 
By chance are you using an XY (hor/ver) board from a 4700 (13") instead?

No, its the one that came with the monitor and I also swapped in a known good one. Why would that affect the HV?

The picture is displaying about 4" X 8" in the center of the screen. Im sure its caused by the low HV.
 
Just a shot in the dark here but what about that black axle cap on the right back side of the board. It's a hi voltage cap and I think it has something to do with the screen voltage and one end goes to ground. I know they will cause the HV to burp causing the screen to jump like the picture has a nervous tick. Like I said just a guess. Could be a bad flyback. I had 2 go bad recently but they both wiped out the HOT.
 
I've had two G0-7's come into the shop (about 1 1/2 years apart) doing this. Took me forever to figure the first one out. Someone had previously changed the HOT, and reversed the two wires that solder to it's legs. I had the second one fixed in 60 seconds :). Probably not your problem, but throwing it out there as a slight.....maybe. BTW: the HOTs were still good.

Edward
 
I've had two G0-7's come into the shop (about 1 1/2 years apart) doing this. Took me forever to figure the first one out. Someone had previously changed the HOT, and reversed the two wires that solder to it's legs. I had the second one fixed in 60 seconds :). Probably not your problem, but throwing it out there as a slight.....maybe. BTW: the HOTs were still good.

Edward

I verified the wires on the hot were on correctly when I swaped them out.
I will try changing the other cap and see what that does.
 
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