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imfuraisoth

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My vertical position image on my nanao chassis is not able to be adjusted. I can't move the image up or down. It's not the controller either because I tried another one that I know works and that one doesn't work either. It looks like it wants to move and shifts slightly but never really moves up or down. Any idea why it's not working? The V size and horizontal size and position all work fine. Just V position doesn't respond. Any ideas would be greatly appreciated.
 

imfuraisoth

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I don’t know the exact model but it is a nanao out of my Astro city. So an update, after playing on it for a while, it actually fixed itself. However, I turned it on again today and it went back to the bad behavior.
 

Aurich

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I'm not a monitor repair expert, I've stumbled my way through fixes, but hardly at the level some others are here.

That said, if you have a problem that "fixes itself", on any level, I'd do a recap before worrying about anything else. Have you ever recapped this chassis?
 

nem

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It's either a MS8-29 or a MS9-29. Does your remote have horizontal and vertical hold pots on the remote? If it does, it's a MS8. If it doesn't, it's a MS9.

My guess is it's either a bad connection on the harness or a faulty pot.
 

imfuraisoth

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It is a MS8-29. I have not recapped the chassis and the last chassis I did recap ended up dying on me so I'm going to go about recapping this one unless I absolutely know it needs it. It could be a bad connection on the harness. That's the next thing I'll try to check.
 

Mukuro_W

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i have repaired this issue on a nanao MS9, Q403 was faulty, on the MS9 Q403 or Q404 can cause this issue in V. Position, now I have not an MS8 29 near me but I think that there should be two transistors near the Vertical Ic (LA7832) , test both, this only if your V. Position pot is known to be working. From a photo of the PCB those could be the one green and one black just in front of the V. Out Ic.
 
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imfuraisoth

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I unplugged the controller and cable and plugged my other one in and it worked fine. I replugged in my controller and things worked again. But now, I still got the issue I posted in another thread where the horizontal gets stretched for no reason but goes back to normal after a little bit. I’m thinking maybe this controller or controller cable just has issues.
 

Mukuro_W

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If the h. Size trimner is ok then the issue is due to one or more bad solder joints under the H drive Transformer, on every chassis it Is located on the h stage just near the HOT.
 

twistedsymphony

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As much as people swear by recapping monitors, I've probably had more monitor failures due to bad pots than bad caps.

on both of my MS8s I've replaced every pot on both of them after frustration with ones that were falling out of adjustment or failing to respond to adjustment.
the original pots on these chassis are incredibly cheap/crappy it's worth replacing if you're having issues.
 

Mukuro_W

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Ms8 chassis getting old, in my opinion it deliver a better picture in 15khz than MS9 wich is obviously better designed and maybe the most reliable chassis ever made.
I use Wd-40 and then a no oil contact cleaner based on isoprop alcohol to remove any oil residue but in most cases it is only a temporary fix, the best way is obviously replace.
 

imfuraisoth

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AlxUnderBase

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As much as people swear by recapping monitors, I've probably had more monitor failures due to bad pots than bad caps.
It's any place where the values the trimmer pots from MS8-29 chassis are noted ? looking on schematic and i didn't understand what values are there
 

stj

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number one problem in monitors is actually cracked solder joints.
unfortunatly people often manage to ignore them until something else fails
 

imfuraisoth

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I ended up ordering that replacement controller. I'll see if the issue goes away when I replace it.
 
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