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NAC Monitor Issue

dunpeal2064

dunpeal2064

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Hello,

I have an NAC that is having an issue where the right side of the image will collapse in a bit every now and then. At worst, this will cause both sides of the image to collapse, and this sometimes causes the monitor to turn off completely, and on power cycling the cabinet, the monitor won't turn back on unless it rests for some time. When this happens, the monitor does not power on at all, but the lamp and speakers still power on. I've uploaded a video of this issue happening to Youtube as well. Aside this issue, the image overall appears to have some waviness to it.

View: https://youtube.com/shorts/e1Mps6UTSJw?feature=share


I just had the monitor shipped from Southern CA to Central CA. Prior to shipment the cab was not displaying these issues, and the person that delivered the cab is well trusted. However, we did have to push the cab a bit to get it in the game room, so I imagine its possible something was jostled a bit.

I am testing with an MVS motherboard, with both a Puzzle Bobble and 161-in-1 cart. I don't have another board to test, I'm not sure if the board itself could cause an issue like this.

I am very new an inexperienced with arcade cabs, so hoping someone might be able to give me some pointers. Thanks!
 
This is almost 100% a bad solder joint or two somewhere. I doubt the monitor was really mishandled but in my/@aperturegrillz's experience on maybe 100 of these it's very common to run into this issue and it would not surprise me to see it pop up after being moved. Is this an MS8 or MS9? Both are pretty commonly found in NACs as operators never seemed to really care about downgrading them to MS8s; if you let me know which it is I can give you some points to look at that are likely to be the cause. The shutdown / not powering up for a while thing is a built in protection to stop the monitor chassis from blowing itself up spectacularly under certain modes of failure (locked transistors, no horizontal deflection etc), so don't worry too much about that happening as it will go away when the underlying cause is solved.
 
kevinddr said:
This is almost 100% a bad solder joint or two somewhere. I doubt the monitor was really mishandled but in my/@aperturegrillz's experience on maybe 100 of these it's very common to run into this issue and it would not surprise me to see it pop up after being moved. Is this an MS8 or MS9? Both are pretty commonly found in NACs as operators never seemed to really care about downgrading them to MS8s; if you let me know which it is I can give you some points to look at that are likely to be the cause. The shutdown / not powering up for a while thing is a built in protection to stop the monitor chassis from blowing itself up spectacularly under certain modes of failure (locked transistors, no horizontal deflection etc), so don't worry too much about that happening as it will go away when the underlying cause is solved.
Click to expand...

Thanks for the quick response!

I believe its an MS9, but I will have to open it up to confirm, which I assume I'll need to do to check for those solder joints. Bit of a bummer but hopefully not too difficult a repair!

I have been testing just to try to figure out what I can, and the issue does appear differently depending on what game is booted up. I imagine that doesn't rule much out though.

I'll see if I can get it opened and get some pics where the bad joints might be tomorrow.
 
Give it a once-over with a microscope. Sometimes on the larger joints you can see the cold/cracked joints with the naked eye. You can also just reflow a bunch of stuff and see if it helps.

Worst case, if you're in LA area, take it to PNL and let John deal with it.
 
kazuo said:
Give it a once-over with a microscope. Sometimes on the larger joints you can see the cold/cracked joints with the naked eye. You can also just reflow a bunch of stuff and see if it helps.

Worst case, if you're in LA area, take it to PNL and let John deal with it.
Click to expand...
I'm about 6 hours out of LA, but might still be worth considering to have it repaired by someone that knows what they are doing. Though if there is anyone in the bay area that offers that service, that might work better.

The monitor itself is like mint, so I'd be happy to pay for this issue to be resolved and have what is otherwise a dream cab up and running.
 
Something similar happened to mine before. A reflow on all the power supply section fixed it. The nanao ms9 chassis runs really hot and this causes a solder joint to crack or become loose. While at it it would be suggested to also recap that section. A reflow means to add more solder to the joints if you have not done this before.
 
dunpeal2064 said:
I'm about 6 hours out of LA, but might still be worth considering to have it repaired by someone that knows what they are doing. Though if there is anyone in the bay area that offers that service, that might work better.

The monitor itself is like mint, so I'd be happy to pay for this issue to be resolved and have what is otherwise a dream cab up and running.
Click to expand...

Do you have any soldering experience? In this hobby, it's probably worth having at least some ability in this regard, but totally understand if you don't want a monitor chassis to be your first rodeo (I wouldn't). PNL also accepts mail-ins. Best practice is to call and make arrangements if you decide to go that route.

For soldering practice, lots of tutorials on YouTube. You can buy something cheap like a KSGER T12 clone iron on Amazon or something, then pick up some junk electronics from a thrift shop and just go nuts on it. Better to practice on junk than stuff you want to keep.
 
kazuo said:
Do you have any soldering experience? In this hobby, it's probably worth having at least some ability in this regard, but totally understand if you don't want a monitor chassis to be your first rodeo (I wouldn't). PNL also accepts mail-ins. Best practice is to call and make arrangements if you decide to go that route.

For soldering practice, lots of tutorials on YouTube. You can buy something cheap like a KSGER T12 clone iron on Amazon or something, then pick up some junk electronics from a thrift shop and just go nuts on it. Better to practice on junk than stuff you want to keep.
Click to expand...

Yeah that is a good point, it might be in my best interest to learn the skill myself in case future issues pop up, rather than ship out the chassis every time something happens. I did take a couple years of electronics classes where we soldered in high school, that was ages ago but I at least have the basics down. I'll watch some tutorials and start practicing, never hurts to learn a new skill!
 
I had the exact same issue with a MS9 before, the MS9 has a "wide" and "narrow" jumper on the chassis. I had a bad solder joint just around that jumper cable
 
Did you mess with the fingerboard at all once you got it up and running? Try wiggling the horizontal size pot and see if it does anything. Could be a pot starting to go bad. Had this happen before.
 
scaryhours said:
Did you mess with the fingerboard at all once you got it up and running? Try wiggling the horizontal size pot and see if it does anything. Could be a pot starting to go bad. Had this happen before.
Click to expand...

I did turn the horizontal size pot, it does increase and decrease the screen size, but not past where that collapsing is happening, and if I increase it past that point the image gets squished on the sides.
 
kevinddr said:
This is almost 100% a bad solder joint or two somewhere. I doubt the monitor was really mishandled but in my/@aperturegrillz's experience on maybe 100 of these it's very common to run into this issue and it would not surprise me to see it pop up after being moved. Is this an MS8 or MS9? Both are pretty commonly found in NACs as operators never seemed to really care about downgrading them to MS8s; if you let me know which it is I can give you some points to look at that are likely to be the cause. The shutdown / not powering up for a while thing is a built in protection to stop the monitor chassis from blowing itself up spectacularly under certain modes of failure (locked transistors, no horizontal deflection etc), so don't worry too much about that happening as it will go away when the underlying cause is solved.
Click to expand...

Finally had time to at least open up the back to check, and from pictures online it looks like it is a MS9 chassis. I'm gonna work on pulling the monitor this weekend, if there are some key spots to look for other than what's been mentioned that would be super helpful!

Appreciate everyone's assistance, feeling confident I can get this up and going again.
 
dunpeal2064 said:
I did turn the horizontal size pot, it does increase and decrease the screen size, but not past where that collapsing is happening, and if I increase it past that point the image gets squished on the sides.
Click to expand...

Do you have a spare fingerboard? It sounds like the horizontal size adjustment pot could be going bad, that's exactly what happened with mine.
 
scaryhours said:
Do you have a spare fingerboard? It sounds like the horizontal size adjustment pot could be going bad, that's exactly what happened with mine.
Click to expand...

No I don't unfortunately, that would be a much easier thing to check if I did. I started looking around but am mostly just finding replacement parts, so I can look into replacing that pot as that is still probably less work than pulling the monitor.
 
dunpeal2064 said:
No I don't unfortunately, that would be a much easier thing to check if I did. I started looking around but am mostly just finding replacement parts, so I can look into replacing that pot as that is still probably less work than pulling the monitor.
Click to expand...
D

FS Thread '( FS) Remotes with Extended Menu ( New net city and PFX ), Reproduction of remotes ( MS9-29 , MS8-29 and more ... )'

Hi all,

Remote with Extended Menu fo New net city and Egret 3

Remote boards with Extended Menu for New Net City and Egret 3 with Toshiba chassis only.
It allows to set geometry, colorimetry and high contrast mode to fine tune the picture which is impossible with the original remote.

IMG-1804.jpg


IMG-1805.jpg


As you can see, it fits like a glove in place of the original one, it's just a matter of removing and replacing two screws and reattach cable.

IMG-1807.jpg


IMG-1808.jpg



Asking 40 euros per board.


Remote Sanwa PFX Extended menu

Remote for Sanwa PFX...
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He makes reproduction remote boards. Check it out! Not saying this is 100% your issue, but an inexpensive possibility!
 
opt2not said:
If you're going to replace the remote board completely, you can get Snakegrunger's repro. Slightly cheaper, after currency conversion and you will save on shipping since it's coming from within Cali.
https://pxlmod.com/products/nanao-ms9-29-arcade-crt-remote-board


BUT, those Size/Position pots are easily replaceable and cheaper than buying a full repro remote board.
https://www.digikey.com/en/products...B103/PTV09A-4015F-B103-ND/3781113?so=59270420
Click to expand...

This is perfect, I'll go ahead and snag one of these. Worst-case, it doesn't solve the issue and I have a backup remote board for any future needs.

Appreciate it!
 
You can also try deoxit on the pots. Spray it inside and work the pots back and forth, it can revive most scratchy pots and is a must-have for anyone working with old electronics. You can also try turning the H.S. Limit pot on the chassis which is also in the width circuit.

Personally I would not expect a pot problem though. If it's a solder joint problem, try using the handle of a screwdriver and tapping on the frame. If the problem occurs or goes away when you tap it, then you know that's definitely the problem. Also, has the monitor been recapped?
 
trashedcabs said:
You can also try deoxit on the pots. Spray it inside and work the pots back and forth, it can revive most scratchy pots and is a must-have for anyone working with old electronics. You can also try turning the H.S. Limit pot on the chassis which is also in the width circuit.

Personally I would not expect a pot problem though. If it's a solder joint problem, try using the handle of a screwdriver and tapping on the frame. If the problem occurs or goes away when you tap it, then you know that's definitely the problem. Also, has the monitor been recapped?
Click to expand...
Good info as well, thank you!

When you say to tap on the frame, you mean the outer shell of the cabinet right? I currently have the back panel off as well to inspect what I've found to be problem solder joints from other places online, and I suspect that it has not been recapped.

I just got all my solder stuff in and have a busted ps2 that I may work on as practice, if I feel comfortable enough I may look into recapping it.
 
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