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Nanao Ms-9 monitor doesn’t work after replacing capacitors

Orbit87

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Hey I have egret 2 arcade machine with nanao ms-9 monitor (added photo of the exact version)
M

I did a full recap on a MS9-29 chassis (MS9-29ND22W) and now it won't power on:

No neck glow, no HV, no chirp on power-up

Mains cap gets around 150V, so AC input is fine

B+ hits ~109V briefly then slowly drops to 0V.

About a minute after unplugging, I get a single faint chirp

C4692 removed and tested good

2SK1531 also tests good

B+ cap resistance is around 77kohm.

Has anyone run into something similar on MS9? Would appreciate any tips.

Thanks in advance!
 

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Check all solder joints on the neck board.
I did checked
And I took it to a friend with experience. He tried to activate the monitor outside the machine with a cable he made. Is there anything special he needs to do in order to activate outside the machine? Or it’s as usual?
 
Did you reflow the joints?

I’ve had multiple ms9 chassis with bad solder joints on the neck board. Some of them did look visually OK (but were actually bad).
 
Did you reflow the joints?

I’ve had multiple ms9 chassis with bad solder joints on the neck board. Some of them did look visually OK (but were actually bad).
I did
And still didn’t work
Really weird I’ve double checked everything like 5 times
 
Check all caps again for correct orientation. Also check for lifted solder pads at each cap. Check continuity at each leg on every cap.
 
If it was working before the recap then its certainly something wrong with the recap job. It's pretty easy to lift pads on these chassis, try pushing down lightly on each cap while checking solder side, I had one that would push itself out with the pad.

+1 for check orientation and also any damaged traces/pads/bridges etc.
 
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