Opinions; Neo Geo Game Cartridge issues, I think

cjs001

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I have two games that are giving me issues on my Neo Geo MVS 4 Slot.
Metal Slug: Green lines on along the left and right side of the screen, but then the whole screen with have green lines sometimes.
King of Monsters: will have vertical lines every .25" on the screen

I thought maybe voltage issues may be a culprit. the 5 volt at the jamma plug metered at 5.26 volts. I then tested the 5 volts on the board at the two points in the attached pictured. That spot measured 5.17 volts. The power supply appears to have no ability for adjustment. The other two games are working normally Aero Fighters 2 and Samurai Showdown (aero fighters sometimes seems to momentarily go into slower motion when there is a ton of activity on the screen, not sure if thats just a quirk of the game). I swapped around the games putting the working ones in the slots where the two problem games where and visa versa. Aero Fighters 2 and Samurai Showdown in their new slots are working the same, no issues. Now Metal Slug instead of the green on the left and right side of the screen, it just has a 1/2" of the vertical image missing on the left and right side, but in that missing image "bar" the image is present for the last 1/2" of that bar at the bottom of the screen. King of monsters in its new slot does not have the green lines now but when the pcb is cycling through the games during demo (set to change every 30 secs) it will not cycle past king of monsters, it just sits at the games title screen.

I did take the games apart and cleaned the connectors with a pink eraser and their nice and shiny again. Is there anything else I may be missing I should try before I see if I can find someone to repair the cartridges. Thank you.
 

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I thought maybe voltage issues may be a culprit. the 5 volt at the jamma plug metered at 5.26 volts. I then tested the 5 volts on the board at the two points in the attached pictured.

those voltages are too high
you want the +5 volts dc at +5volts dc

game carts fail
show me anything man made that doesn't break down
no telling how many hours are on those carts
they did good for a long long time

last thing you want to do is put a nice working cart in there with the voltage too high like that
capacitors dry out and that changes the arithmetic equation and adjustment doesn't work anymore

good that you cleaned one side of the pins
could be a piece of dirt in there on the other side
combination of vacuum and compressed air can dislodge the obstruction sometimes, if there is one
pins get weak over time and usage. maybe they are good for 25 times if I remember correctly

have a one slot with a brand new 161 in 1 for sale for 220 shipped to the lower 48 if you want. works 100%

I know of no one who fixes them but so what do I know

good luck

good luck
 
not sure if it's worth the money to find someone to repair the carts.

if you're 100% sure it's the carts, and you've gone the route of cleaning them already ... you may (for the cost) just wanna replace 'em
 
those voltages are too high
you want the +5 volts dc at +5volts dc

game carts fail
show me anything man made that doesn't break down
no telling how many hours are on those carts
they did good for a long long time

last thing you want to do is put a nice working cart in there with the voltage too high like that
capacitors dry out and that changes the arithmetic equation and adjustment doesn't work anymore

good that you cleaned one side of the pins
could be a piece of dirt in there on the other side
combination of vacuum and compressed air can dislodge the obstruction sometimes, if there is one
pins get weak over time and usage. maybe they are good for 25 times if I remember correctly

have a one slot with a brand new 161 in 1 for sale for 220 shipped to the lower 48 if you want. works 100%

I know of no one who fixes them but so what do I know

good luck

good luck

Thank you. Since I can't find an adjustment pot on the power supply, guess I'll pick up a new one so I can actually dial it in instead of trying to recap the original one hoping that it then drops to correct voltages.
 
Update: New power supply came in today. Installed and now set so the pcb board is getting 5 volts at that test spot I used. King of Monsters doesn't have any graphic issues now, and Metal Slug doesn't have the green fuzzy color pulsing, but it is still missing some graphics on the right and left side of the screen. I'll take it apart again and clean its edge connectors again for the hell of it. So now 75% of the games are working correctly, one more to go.
 
Update: New power supply came in today. Installed and now set so the pcb board is getting 5 volts at that test spot I used. King of Monsters doesn't have any graphic issues now, and Metal Slug doesn't have the green fuzzy color pulsing, but it is still missing some graphics on the right and left side of the screen. I'll take it apart again and clean its edge connectors again for the hell of it. So now 75% of the games are working correctly, one more to go.

I've never taken apart a cartridge so I don't know how big the game board is in there.

I would assume they are different sizes. different sized boards require different adjustments of the +5 volt.

what I would try is to just run the problem board by itself and adjust the +5 volts up till hopefully it works.
its already broken and turning up the +5 volt might show you if its actually broken or if it doesn't have enough +5 volts

hopefully the problem board works but can only be used on a 1 slot
but I don't know
don't want you to condemn it when all it needs is more 5v

good luck
 
I've never taken apart a cartridge so I don't know how big the game board is in there.

I would assume they are different sizes. different sized boards require different adjustments of the +5 volt.

what I would try is to just run the problem board by itself and adjust the +5 volts up till hopefully it works.
its already broken and turning up the +5 volt might show you if its actually broken or if it doesn't have enough +5 volts

hopefully the problem board works but can only be used on a 1 slot
but I don't know
don't want you to condemn it when all it needs is more 5v

good luck

The game is working but just missing some graphics, I'm just ocd and like to get everything fully working, but worst case I live with it bc it doesn't affect game play at all. Picture shows whats missing
 

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I think those little blocks are normal, because I can set MAME to standard 4:3 mode and it will show those. If I set it to the Neo Geo's slightly smaller resolution of 304x224, the black borders on the left and right are gone. You just need to adjust the horizontal size on your monitor to hide those bars.
 
I think those little blocks are normal, because I can set MAME to standard 4:3 mode and it will show those. If I set it to the Neo Geo's slightly smaller resolution of 304x224, the black borders on the left and right are gone. You just need to adjust the horizontal size on your monitor to hide those bars.

okay thank you! For the screen adjustment, when I get the crosshatch pattern on the screen, it has a blue perimeter, are you suppose to adjust so there is no blue on the screen?
 
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You'll want to adjust it so that the blue border is around the edge of the screen.
 
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