Astro City monitor

[Atari FGC]

I have a couple Astro City cabs. One of them just went through a complete re-capping as well as some work to fix the vertical display, as it was all crammed tightly in the middle of the screen. This turned out to be very expensive to repair and included me having to transport the cab to and from the repair shop (the vertical had been working if you gave it time to warm up and tapped on it, but then that stopped working). My other cab is now experiencing some flickering if you hit the buttons or stick hard (can happen during normal play) or if you tap on the side, and then this goes away after several minutes of warm-up time. I'm sure this is repairable, but I'm wary of doing another expensive job when perhaps replacing the chassis would solve everything. With recapped/tested/working chassis available on Ebay in the $125 range, this seems like perhaps the more sensible thing to do.

With that being said, based on what I can see on Ebay, there are several different chassis available for my monitor (it is definitely Nanao, but I actually need to determine if it is MS8 or MS9). My question here is, is there a way I can figure out what the correct chassis to buy would be? There are many sub-models and I am concerned about getting the right one. Would there be a specific one for an Astro City? Or do I need to open it up and look for stamps/decals? Any guidance would be very helpful!

thanks

 

[PascalP]

Stock NAC should have MS9, but your issue you describe could be a could solder joint.
So I would start with pulling out the chassis and examining the solder joints closely.

There are some variants of MS9 though, MS9T and MS9S if I’m correct.
Difference is manual degauss vs auto degauss from memory, but I could be wrong here...

 

[opt2not]

Stock NAC should have MS9, but your issue you describe could be a could solder joint.
So I would start with pulling out the chassis and examining the solder joints closely.

There are some variants of MS9 though, MS9T and MS9S if I’m correct.
Difference is manual degauss vs auto degauss from memory, but I could be wrong here...

oh I thought the difference was one has the auto-switching relay for 15 - 24khz, while the other is just a wired plug you have to manually switch...

 

[PascalP]

Stock NAC should have MS9, but your issue you describe could be a could solder joint.
So I would start with pulling out the chassis and examining the solder joints closely.

There are some variants of MS9 though, MS9T and MS9S if I’m correct.
Difference is manual degauss vs auto degauss from memory, but I could be wrong here...

oh I thought the difference was one has the auto-switching relay for 15 - 24khz, while the other is just a wired plug you have to manually switch...

Might be that as well...
Like said, I'm not sure, one has something auto and one has something manual

But the MS9S I've seen in NAC and Cyberlead cabs have both degaus and resolution switch manual anyway.
I think the MS9T used in Taito cabs (Egret 2?) have something automatic

 

[The Spaniard]

My MS9 has no separate switch for 15/24khz and manual degauss on the PSU if that helps.

Forgot what version of the MS9 this is but there is a way to tell by the pots on the edge of the PCB on the right side of that picture there.

 

[PascalP]

Yup, that black relay in the middle is for the 15/24KHz switching.
Must be a MS9T then...

 

[opt2not]

Yup, that black relay in the middle is for the 15/24KHz switching.
Must be a MS9T then...

Yeah, I had 2x NACs one with and one without that auto-switching relay. If it wasn't there, you'd see a 2 prong (Green and Brown wires if my memory serves me) plug and headers in that spot.

The auto-switching is nice if you're connecting med-res hardware to your NAC. I used to have a Dreamcast connected through an Ultracade UVC (down-rezzes 31khz to 15 or 25khz) and the image quality was amazing.