What's new

Treating the dimness of my Sega Net City / Nanao MS-2933

brandon.arnold

Student
Joined
Jan 1, 2022
Messages
85
Reaction score
72
Location
Seattle, WA
Hey all. The monitor in my Net City has become more dim over time, and I wish I could do something about it. I wonder if someone could answer some questions!
  1. How likely is it that this is simply the phosphor layer, and unfixable? If it is the gun, I do have a good rejuvenator (Sencore) but have been afraid to try it.
  2. I don't see any chassis for this monitor on Ebay, but I see a few for other similar Sega cabinets (Aero City, Astro City, Blast City). Are any of these interchangeable with the one for the MS-2933? I would be open to the convenience of getting one with all the components replaced.
  3. Assuming I can't do (2) and there is a benefit to trying, would it be adequate to try a re-cap of my board, and replace the flyback?
Edit: Monitor model is actually MS-2933, not MS-2931
 
Last edited:
Definitely start with a recap of the board and adjust/calibrate the colors/flyback after the recap. I would not change out the flyback unless it's broken. If the chassis works, then the flyback is not broken....

You should also try the Sencore to simply check the health of the tube. you don't have to zap it if the guns test healthy.
 
IMO people are overly scared of rejuv jobs. There really isn't a reason to be scared of them, they're not actually crazy harsh unless you seriously crank all the dials and cook things. And really, what's the point of owning a Sencore but not wanting to use it? I agree with the above people, at the very least hook that bad boy up and see the results. And afterwards, run some low level rejuv and see if you notice a difference. (It's unfortunately not a silver bullet.)

If nothing else though you'll have some data. If all the tests are good then you know that's probably not culprit.

Replacing the chassis isn't really a great solution to avoiding a recap, because you're just going to end up with a chassis that probably has old caps too. If you'd like to throw money at the problem instead of doing your own recap I can respect that perspective, but I think you'd end up with better results paying someone to do a nice clean recap and know you have new parts instead of playing a gambling match with likely spending more than someone would charge for that service to get a new replacement part that could be just as bad or worse.
 
Oigan todos. El monitor de mi Net City se ha oscurecido con el tiempo y desearía poder hacer algo al respecto. Me pregunto si alguien podría responder algunas preguntas!
  1. ¿Qué tan probable es que esto sea simplemente la capa de fósforo y que no se pueda reparar? Si es el arma, tengo un buen rejuvenecedor (Sencore) pero he tenido miedo de probarlo.
  2. No veo ningún chasis para este monitor en Ebay, pero veo algunos para otros gabinetes Sega similares (Aero City, Astro City, Blast City). ¿Alguno de estos es intercambiable con el del MS-2931? Estaría abierto a la conveniencia de obtener uno con todos los componentes restantes.
  3. Suponiendo que no puedo hacer (2) y hay un beneficio en intentarlo, ¿sería adecuado probar una nueva tapa de mi placa y reemplazar el flyback?
If you want parts there are a couple of options, the easiest is eBay where they hardly ever have anything or with high costs due to shipping and speculation fees, then you have the other two options which are the most sensible buy the parts from Japanese sites. and pay the import and shipping fees or you will eventually find what you need on this forum and a few others like arcade Otaku and the like.



You'll also probably have some local buy and sell sites in your area, though depending on where you live you'll have more or less chance of finding the item.



In my case I usually buy everything in Japan and I'm a Fedex customer because of the discounted shipping, so if there's anything for sale on the forum I'll keep an eye out.



Right now I'm accumulating parts for my new net city restoration and I'll probably have a lot left over and I'll post them on the forum, except for the most essential ones.



In Yahoo Japan sometimes there are quite a lot of Chassis
 
Last edited:
You should also try the Sencore to simply check the health of the tube. you don't have to zap it if the guns test healthy.
I have checked it out and the tube seems to get a "GOOD" test result for cutoff, low/high tracking, and emissions. Here are the settings I used for anyone curious.

sencore_manual_a68ksm696x.png
IMG_3825.jpg
IMG_3823.jpg
IMG_3824.jpg
 
Last edited:
Hello there you will want to glance through the cr7000 manual. Those emissions are in the "bad". You will want to look closer to this:
 

Attachments

  • 20221010_190617.jpg
    20221010_190617.jpg
    223.4 KB · Views: 86
Well, that was a disappointing outcome! I think my monitor is finished. X/

I went through all the test steps again, making sure to get the filament voltage right this time, and my green gun was the one that was in the "bad" region, for emissions. After performing a couple of "reactivate" functions, I did not see any improvement. Then I did the low repair option (again, only on the green gun). This made things significantly worse, unfortunately. It fixed the emissions on the green gun, but now my green gun fails the test for low cutoff, for gun tracking, and for G1 short. After going back to do the G1 short repair on the green gun, that seems to have fixed it somewhat (though not nearly as good as it was) and the low cutoff and gun tracking are still broken.

The picture, when plugging back Tetris The Grand Master 2, is pretty bad. I think green is just very dim (thought the green menu is bright and crisp) in the game.

In the morning I will try to rejuv with the higher functions, since it seems pretty far gone at this point.
 
Last edited:
Hey y'all. I did some more work on it earlier with the Sencore and it actually is in a much better place. It did not work miracles--the gun tracking still checks "bad" on both Low and High cutoff tests. But the cutoff actually does work on the green gun, now, and emissions are in the "good" range for everything. Furthermore, the monitor is most definitely brighter in-game, and looks better than it did when I started. So things are much improved. I am actually interested to recap, too, at this point.
 
With bad emissions youre on life support. Sometimes you can recover it. But might last 3-6 months. Less or more. Caps wont help at this point as you know.
 
Back
Top