Sega Nanao MS7-20S Vertical Collapse

mrdude

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So I'm repairing a monitor that had a cracked neckboard that was "working" before the game magically stopped one day. The previous owner was kind enough to tell me that he pulled the monitor out and cracked the neckboard in the process. I've since repaired it, I think, but I've got vertical collapse. I feel like I might have missed something, but maybe not.

I can't seem to find a schematic anywhere and my monitor knowledge isn't good enough to know where to look. Would this happen to be similar to another Nanao monitor?
 
I'm suspecting bad transistors in the Vertical IC. They seem to be in the same location as other Nanao monitors. I did a diode test real quick but I didn't have time to do them out of circuit, but both should have been reading OL on the Collector to Emitter diode test on my DMM, but one was 1.5v and the other was 1.7v. I suspect they are bad, but we'll see.
 
Cap kit done and transistors replaces even though they tested good out of circuit. Other nanao monitors say to check a resistor and tantalum cap that I can't seem to find on this monitor... of course they are different. But the transistors did line up as far as locations go.

Still no luck. Suggestions?
 
ARRRGHHHH!!!! No such luck with a replacement vertical IC HA11423. WHAT THE FLIP!?
 

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that's a very common ic used in many models

But not likey a problem.

most problems are the last stage of most circuits

because of higher current part.

like q401 and q402

Always need to test for voltage.

do you mind measuring the voltages on the collector base and emitter

don't worry if you don't know what the voltages should be just post them.

you should post a photo of the chassis since it not so common.

I would suspect your just missing the collector voltage that comes from the flyback

if you replaced the transistor which I always replace too.

then test the circuit.

see if they are warm at all.

when a working part is warm odds are its working

if cold I would check if it has voltages on it first.
 
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