Neo Geo MVS 4 Cart, Ver 3. First time Owner/Servicer/Repairman

Devryn

New member
Joined
Jan 19, 2011
Messages
115
Reaction score
0
Location
Coolidge, Oklahoma
Neo Geo MVS 4 Cart, Ver 3. First time Owner/Servicer/Repairman

Good day everyone. :) I'm a first time owner of a Neo Geo that needs some rewiring. It supposedly all works, but some of the wiring is hacked, some of it is missing, and I've never repaired one of these things in my life. Before I start asking questions a little background about me:

First, obviously, I'm an amateur at repairing these things.
Second, I've built computer systems since Pentiums clocked at 100mhz were blazing fast.
Third, I'm not an engineer. Once things get too scientific, I glaze over. I don't understand wiring diagrams. Not that I'm not willing to learn, I've just never had cause to learn.
Fourth, I'm a decent shade tree mechanic.
And finally, I learn quick.

About the machine:
I picked this thing up for $100 two weeks ago. It needed new upper sides, and I suspect this is overall in rougher shape than was revealed. The sides had obviously been exposed to moisture, and the inserts for the marquee are all sun damaged and brittle. The mainboard was so covered in crud, you couldn't make out the chips...I wish I had a before picture of the mainboard...But when I get a task, I just do it. Pics are usually an afterthought.

So here's the cab when I got it.

IMG_20110112_195712.jpg

IMG_20110112_195342.jpg


The mainboard after an hour of cleaning:

IMG_20110116_153845.jpg


Cut and painted new sides:

IMG_20110117_134729.jpg


(continued)
 
New sides on:

IMG_20110117_150010.jpg

IMG_20110117_150308.jpg


Now its time for the mess I call wiring. I've reviewed the service manuals, but my eyes just glaze over at the wiring diagrams. First, the monitor

The pictures below show wiring from the monitor. The white black next to each other I ASSUME are power? There's two other black wires, one that runs from the back of the monitor portion, and one that seems to run from the back of the board somewhere. They look like the should be connected...Not sure what their purpose is.

IMG_20110117_161119.jpg


SUPPOSEDLY, the white black in the picture below is the power wires that go to the white black on the monitor, but that gauge does not look thick enough to me. Thoughts?

IMG_20110117_161038.jpg


Now, on the other side of the monitor is a connector on the board, which is for the RGB from what I gather. I don't have a harness that plugs into it...Is that a plug I can find at radioshack and wire myself? Also, there are two other wires...A two strand orange wire set, and a 4 strand multi color and I have NO IDEA where they go.

IMG_20110118_183528.jpg


(continued...)
 
I found this wire in the cab...First pic is the label the person I bought it from wrote...Any ideas what it's supposed to say/mean? Second pic is of the wire.

IMG_20110118_183639.jpg

IMG_20110118_183706.jpg


Not pictured are the controller cables that have an IDE looking end (don't worry, I've figured out where those go...Pretty obvious LOL), but they have green wires that I assume are grounds..Where do you ground something in a WOOD BOX?

I'm sure I'll have more questions, but we'll start here. ;)
 
congrats on the neo geo score...I have 4 of em and I can't get enough lol...onto some solutions...

The black and white wires are what power the monitor...Don't be concerned with the gauge of the wire....most cabs (neo and dynamos) use smaller gauge wiring up to the chassis. Before you power that thing on PLEASE clean the dust and crud off the chassis as best as you can.

The monitor connector your looking for is missing. You can make one yourself, you just have to get the right connector. when I get home I can post picks of the connector for you...
 
congrats on the neo geo score...I have 4 of em and I can't get enough lol...onto some solutions...

The black and white wires are what power the monitor...Don't be concerned with the gauge of the wire....most cabs (neo and dynamos) use smaller gauge wiring up to the chassis. Before you power that thing on PLEASE clean the dust and crud off the chassis as best as you can.

The monitor connector your looking for is missing. You can make one yourself, you just have to get the right connector. when I get home I can post picks of the connector for you...
Is it a connector Radio Shack would carry?
 
You *might* find a useable solution for the connector at Radio Shack. For the most part RS sucks and is almost entirely useless. Get acquainted with the online parts suppliers. Usually cheaper to buy and ship than pick up from RS anyway...
 
Name that Cable

That last cable looks like the RGB sync going into my 19' imperial. other end is rgb for upper plug (cut off it seems). And lastly the two wire orange connector should be for the degauss wire going around the monitor, plugs in on monitor pcb. Nice wood work and good catch.
 
Which parts suppliers are best?

Digi-Key and Mouser are great, but can be overwhelming depending on what you're looking for. Honestly, http://therealbobroberts.net/ is your friend. He has a lot of great articles on wiring on the site which are simplified as much as possible, and he's got about every part you might need for (usually) the lowest price out there. Only thing is he doesn't take paypal, or credit cards, or any electronic payments. If your bank has online billpay, you can set him up as a payee just like you would your power company/cable company/whatever. When you put an order in the first time he'll send his address.

Info examples:
Wiring a JAMMA Harness (there might be a difference with one of the audio outputs on your neo board depending on which neo board it is):
http://therealbobroberts.net/jh.html
Power supply wiring:
http://therealbobroberts.net/acwiring.html

And so on. Check out the "Big Bear's Bulletin Board" section down the main page for all sorts of goodies like that.

Parts can also be had from jammaboards.com and lizardlick.com, though if you can get past the "doesn't take paypal" part, Bob rules. Just don't screw up and forget to send your check like some have, bad karma abounds for that one. :)

*e* And yeah, very nice woodwork and congrats on the pickup. :)
 
That last cable looks like the RGB sync going into my 19' imperial. other end is rgb for upper plug (cut off it seems). And lastly the two wire orange connector should be for the degauss wire going around the monitor, plugs in on monitor pcb. Nice wood work and good catch.

So does the degauss wire stay plugged into the board on the monitor all the time, or just as needed?
 
Wow, you did inherit a mess of wires. I didn't see a jamma/mvs harness in any of your pictures, it would look like this, http://www.therealbobroberts.net/mvsharness.jpg . That's key to getting this all to work, it connects the NeoGeo board to the monitor/speakers/controls/etc. If you don't have that harness get one from Bob, jammaboards, or lizardlick.com. Just make sure it's wired for MVS and not Jamma since you have a 4-slot board.

Those two wires for degauss are always plugged in and it only fires when the monitor is initially powered in. That single black wire could be the ground from the chassis, it's hard to tell with the extreme closeup and darkness of the picture. If it's ground, there should also be a metal strap wrapped around the backside of the tube which also serves as ground, connect those two together. The white/black pair is indeed power and there should be another pair of wires coming off the isolation transformer near the power setup. Make sure your power assembly looks similar to this, http://www.therealbobroberts.net/buildit.html .

The 4 pin black connector with red/blue/brown/yellow is the yoke connector and plugs into the monitor PCB. It *should* have an irregular spacing between a pair of wires that tells you which way to plug it in on the board.

The small rectangular connector for the monitor should have RGB, Ground, and horizontal/vertical sync (yellow/white). There is a connector on the chassis with 6 pins then a space and then 3 more pins. Generally RGB is on the 6 pin connector and then ground/sync is on the 3 pin connector but it appears you only have the 6 pin connector wire? Although it doesn't really matter because it's not connected to anything else. You might be able to get away with just plugging in the 6 pin connector since all the wires are present. But without the harness on the other side, it doesn't really matter. Try posting a picture of all the wiring you have so we can see what you might still need.

Scott
 
Wow, you did inherit a mess of wires. I didn't see a jamma/mvs harness in any of your pictures, it would look like this, http://www.therealbobroberts.net/mvsharness.jpg . That's key to getting this all to work, it connects the NeoGeo board to the monitor/speakers/controls/etc. If you don't have that harness get one from Bob, jammaboards, or lizardlick.com. Just make sure it's wired for MVS and not Jamma since you have a 4-slot board.

Those two wires for degauss are always plugged in and it only fires when the monitor is initially powered in. That single black wire could be the ground from the chassis, it's hard to tell with the extreme closeup and darkness of the picture. If it's ground, there should also be a metal strap wrapped around the backside of the tube which also serves as ground, connect those two together. The white/black pair is indeed power and there should be another pair of wires coming off the isolation transformer near the power setup. Make sure your power assembly looks similar to this, http://www.therealbobroberts.net/buildit.html .

The 4 pin black connector with red/blue/brown/yellow is the yoke connector and plugs into the monitor PCB. It *should* have an irregular spacing between a pair of wires that tells you which way to plug it in on the board.

The small rectangular connector for the monitor should have RGB, Ground, and horizontal/vertical sync (yellow/white). There is a connector on the chassis with 6 pins then a space and then 3 more pins. Generally RGB is on the 6 pin connector and then ground/sync is on the 3 pin connector but it appears you only have the 6 pin connector wire? Although it doesn't really matter because it's not connected to anything else. You might be able to get away with just plugging in the 6 pin connector since all the wires are present. But without the harness on the other side, it doesn't really matter. Try posting a picture of all the wiring you have so we can see what you might still need.

Scott

Wow! Great reply! Thank you! So the black 4 pin connects back onto the monitor somewhere? I do have the MVS/Jamma harness...I only posted pictures of the things I didn't know...When I get home tonight, I'll post pictures of everything. Thank you so much for all of that information! It's a great help!
 
There should be a row of 4 largish pins that look similar to the pins used for the degauss. Hopefully the yoke cable is cabled such that it only fits one way. If you have the mvs harness, find the wires for video, video gnd, and sync, they should be attached to that 6 pin connector you have.
 
There should be a row of 4 largish pins that look similar to the pins used for the degauss. Hopefully the yoke cable is cabled such that it only fits one way. If you have the mvs harness, find the wires for video, video gnd, and sync, they should be attached to that 6 pin connector you have.

Not at home yet, but the man I bought it from says that black clip is for the gun?
 
Well...I guess sorta. The yoke is what causes the deflection in the tube guns and controls the geometry of the picture. I'm wondering why the guy even unplugged that stuff anyways. He must have separated the chassis from the tube for some reason. But anyways, make sure everything is cabled up before trying to turn on the monitor. Is the neck board hooked up as well?
 
I would resize my photos to 800x600 max to increase readability.

I have the same exact machine and can take pics of anything you would need.
Here's my own restoration thread.
http://forums.arcade-museum.com/showthread.php?t=165601

Many of these monitors were K7000 monitors. The black connector going to the Yoke goes down here under the metal plate.

it's marked here under C38 and the width coil.

k7000lyot.gif
 
Last edited:
I would resize my photos to 800x600 max to increase readability.

I have the same exact machine and can take pics of anything you would need.
Here's my own restoration thread.
http://forums.arcade-museum.com/showthread.php?t=165601

Many of these monitors were K7000 monitors. The black connector going to the Yoke goes down here under the metal plate.

it's marked here under C38 and the width coil.

k7000lyot.gif

Another awesome post! Thank you. I'm tempted to leave work early to get to work on this thing! A quick question...The green wires coming off of the controller cables near the IDE-like end...I ASSUME those are grounds? If so, where do I ground them?
 
Another awesome post! Thank you. I'm tempted to leave work early to get to work on this thing! A quick question...The green wires coming off of the controller cables near the IDE-like end...I ASSUME those are grounds? If so, where do I ground them?

attachment.php


just the hint of it is shown here. Yeah those are grounds. They ground on the metal cover I believe. I'll have to check again. Of course I painted my metal cover so ...
 
O.K. So here are the pictures I promised, and I seriously have even more questions...

I've found the connector that is supposed to be RGB (is that right?), and where it hooks up to the harness INSIDE the cab. The ends are cut, but I BELIEVE they go to that separate wiring connector (mess) that plugs into the monitor in the RGB slot.
Here's the connector for inside the cabinet:

IMG_20110120_183104.jpg


And here's the harness that plugs into the monitor that I believe I'm supposed to splice into the previous connector:

IMG_20110120_184454.jpg


Now...WHY does this connector go from a white wire and yellow wire and at the connector, connect them, into a blue white stripe and white cable? Also, why does the yellow wire have a panhead connector midwire just before the connector that changes the wires color and combines the white and yellow wire?

Also, on the connector in the first picture, there's a black and a black w/stripe wire...What do they go to?

IMG_20110120_183120.jpg




Does anyone know what this is?

IMG_20110120_182739.jpg
 
Back
Top Bottom