SNK Neo Geo - 10 x Neo Geo MVS Board Repairs Part 1 (Z80, Watchdog, SFIX) - MV1A MV1AX Neo-Buf

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A short video covering the repair of the first 3 of 10 Neo Geo boards from a friend.
#snk #neogeo #watchdog #repair #arcade #jamma

[@Four_X]

Brilliant repair's Chris, I'm looking forward to the other Neo Geo MVS repair videos and no I never get bored of watching your videos. On a side note, Ni-Cd batteries you've just got to love them right, best invention ever. FFS. How many Neo Geo MVS's & Amiga 500+ not to mention countless other vintage electronic devices have been totally destroyed because of these nasty batteries. It's so sad.

[@GadgetUK164]

Cheers mate! I am sure these are going to be sending people to sleep as they are sick of Neo Geo stuff lol. Yeah, Ni-Cad batteries are worse than leaky capacitors I think!

[@bwack]

"oh yes !" I know the feeling, fixing stuff :) Awesome video. So many boards, I would have lost track after two boards.

[@GadgetUK164]

Hehe =D I did lose track - when coming to editing I couldnt work out what footage was for which repair etc. The last 3 boards were from HELL, this first 3 were pretty simple compared.

[@georgelea4297]

Love these neo geo videos keep up the amazing work Chris

[@GadgetUK164]

Thanks =D

[@mikepearman6669]

As I’ve said before your a neo god, I love watching your videos and learning from you, and I can’t wait for the payback 🤣

[@Neffers_UK]

**** yeah! Looking forward to the rest of the series Gadge. You are not a simple repair guy, you are a bloody necromancer! ♥ your content.

[@GadgetUK164]

Cheers mate =D The last 3 were hell to work on!!! The last of them just bit me again yesterday as I was packing them all up and testing etc and spotted ANOTHER fault I hadn't noticed yet....

[@nathandivino]

Personally, I don't mind if you show the same thing in multiple videos, I enjoy the process.

[@GadgetUK164]

Thanks =D

[@Beaps73]

Wow just wow. Love that mate

[@GadgetUK164]

Cheers mate =D

[@g412bb]

Are you sure that it's a friend that gave you these? It's more something I would give to my enemies! Good luck on the repairs!

[@GadgetUK164]

Haha =D Yes, I think you're right! Boards 4 to 6 (next parts) were hell to work on!!!

[@JohnGotts]

Yes! Missed you.

[@GadgetUK164]

Thanks mate =D

[@MechaFenris]

Whew... that's some serious troubleshooting. Good show! I would've given up when the sound went out. :) I'm just a quitter... heheh.

[@GadgetUK164]

Hehe, thanks! Wait until you see the last 3 boards! Those were AGONY to work on! Fault after fault after fault...

[@robwebster7406]

Great job 👍

[@GadgetUK164]

Thanks =D

[@GameTechRefuge]

Those Neo Buff chips seem to just fail for fun. Great work on the NEO GEO stuff Gadget, you seem to know these boards inside out. Work here is not going to be as crazy as it has been of late, until after Christmas anyways. Looking forward to spending some time with the soldering iron. Finish the Amstrad PC & do some more SEGA stuff.

[@GadgetUK164]

Tell me about it lol! Wait until you see part 4 with all the faulty chips... There are a LOT lol. I do hope you can find some time for more repairs - it's always interesting to watch!

[@joshb.9380]

Amazing work and great videos! Some of your insights here gives me hope that I might beg some advice from you: I’ve had an MV1 (the original 1-slot) for a few years that is in great condition; no corrosion, clean cart slot, and new 470uf caps I replaced . Plays my carts fine. However, I just got a new Neo SD that is having problems. When the Neo SD menu screen appears, all text is so glitched that it is illegible, though the four button icons and game “thumbnail” are barely visible. I can flash a game successfully, but when game loads, the text beneath the Neo Geo logo is glitched. The FBI anti-drug screen looks perfect. When the actual gameplay starts, the game looks fine except all the text elements, like in the HUD, etc. are glitched. Characters, backgrounds, and all that look fine. It was suggested to me that Neo SD might need higher voltage or use different pins compared to my original carts. I tested a solid 5.1V at JAMMA edge though, and even after repeated cleanings and variations on seating angle for the cart, these same glitches persist, confined to these text elements. These do not occur with my original carts. Please let me know if you have any suggestions; I appreciate your time.

[@GadgetUK164]

It's quite strange that it flashes OK and it seems to be just text elements. Have you cleaned the cart slot up and the cart PCB edges? It sounds like something S layer affected maybe, I wonder if something there is buffered on the MV1 (I will take a look soon when I look at an MV1F).

[@joshb.9380]

Thank you for the reply. Yeah, it really is puzzling me. I’ve cleaned the motherboard contacts and cart edge multiple time with isopropyl alcohol, but no luck. They both seem pristine, and the contacts are not bent and still very springy. I may try to get some Deoxit this weekend and try that, but I don’t hold out much hope. Thanks for your attention; I’m so close to Neo Nirvana! 🥲

[@joshb.9380]

​@@GadgetUK164 Troubleshooting update: After more cleaning, same results. However, on a whim, I decided to dial down the voltage, even though I have 5.1V at JAMMA edge. Surprisingly, the more I dialed it down, the more the glitched text began to clear up. At about approx. 4.5-4.6V, the static on the Neo SD game select screen vanished completely. If I hit B to go into the options menu, that screen showed the glitch, but the static would disappear as soon as I backed out to the game select screen. I let it sit at game select screen for 30 minutes and didn't see a single speck of glitchy text. I then tried starting a game and, sure enough, the game played beautifully with no glitched text, although I had to dial the voltage back up a bit to keep the game from repeatedly restarting. However, even at a slightly higher voltage, the in-game text glitches did not reappear. However, as soon I used the input combination to jump back to the game select screen, it was a glitched mess again. To restore it, I had to turn the cabinet off for awhile, then fire it back up at the low voltage again. Perfect-looking game select screen. So, the best I can tell, I have to cold start the machine at a very low voltage, start my chosen game, then dial the voltage up just high enough so that the game doesn't repeatedly reset. I'm guessing maybe I have a capacitor or other discrete component that is failing and introducing voltage spikes that the Neo SD doesn't like? Maybe by dialing it down, I'm keeping the spikes low enough that it can run ok? I think I've replaced all the caps on the board except those that are specific to the audio circuit....could those still be the culprit? The wiring in the Big Red is original, but I did put a new power supply in it, a Suzo Happ LT-200W-1R. I will keep you posted with anything else I find or am able to fix, also for the benefit of any other viewers who may have similar issues. Also, maybe my new discoveries will help you think of other suggestions; I'd welcome any ideas.

[@stevenkeith7190]

Yet again brilliant diagnostics. top repairs. ever considered Synthesiser repairs.???

[@GadgetUK164]

Thanks =D Yes, I have repaired a couple of synths in the past (not on my channel yet though)!

[@MARCOSFERREIRAROCK]

Parabéns muito bom trabalho

[@worzysp1]

This is what I'm getting now when I turn it on Was working

[@worzysp1]

But just after I just lifted the console up off the cupboard held it up and it started working 💪 🙌

[@elkame-lx1lz]

Master!!!!!

[@josephneale10215]

Nice

[@starscanseeme]

Do you do repairs for anyone? I have 4 mvs 4-slots that I think need some attention. (haven' t tested them yet) Great work you do, interesting to watch.

[@GadgetUK164]

Thanks! I cannot do customer repairs sorry! I have a full time job and long term health issues too =/

[@starscanseeme]

@@GadgetUK164 ok, no worries take care !

[@salvatorecavallo337]

Hello, I have been following your videos hoping to find something about a fixed colored checkered screen, following a fast surge of about 5.7 volts. Could you tell me which IC is more sensitive or where to find mvs schematics. I know the video is 3 years old but I hope for an answer, thank you.

[@GadgetUK164]

It could be anything - basically you need to try with the SMK Dan Diagnostic ROM, and if that wont boot start looking at clocks and the data bus, maybe remove some things from the databus side if it looks borked.

[@mickmickymick6927]

Can you put a chip into vinegar to remove the corrosion or would that destroy the chip?

[@GadgetUK164]

Yes, you can do that! But, since its also corrosive - limit how long you leave it there. I have in the past soaked badly corroded (alkaline) ICs in vinegar for an hour or so, and then cleaned them up with IPA and Fibreglass pen etc. It can work well.

[@mcg6762]

Good job! But Christ, your soldering iron looks like something you found by the side of the road. You should treat yourself to a new soldering station mate. Thanks a lot for your interesting videos!

[@GadgetUK164]

Haha :o) Don't worry - it WAS swapped out (not sure if its in part 2 or part 3 - I spotted when I swapped it yesterday when trying to do some editing. So don't worry, it has been swapped a number of weeks ago. This is just old footage.

[@leandroovermind5553]

Nice Video ! hey my board (snk mvs hard) appear (Work rco vgsv) would you know how to solve this problem? )=

[@GadgetUK164]

What is the fault or error - how does it behave?

[@bl1gh7y]

Where would you look if you was having problems with larger games with bank switching only?

[@GadgetUK164]

On which model MVS?

[@bl1gh7y]

@@GadgetUK164 it’s a aes 3-4

[@jeromepader8940]

Hi. Can you help me I have the same problem as you my mvs2 card makes me a click of death even with a bios diag

[@GadgetUK164]

2 slot? It's going to be something on the main databus causing the problem, more than likely. Are there any neo-buff ICs on that rev board?

[@michaellowery1559]

Wheres your duratool desoldering station! Or is this a old video ?

[@GadgetUK164]

Hehe =D This is old footage! The duratool is still here and working super well!

[@Heru3005]

Film this before the new desolder station? 4:30

[@GadgetUK164]

Yeah =D I started these repairs a while back!

[@josuearana8756]

Could You please share us your dia bios the think si the Neo Geo page doesnt work .bin

[@GadgetUK164]

smkdan.eludevisibility.org/neo/diag/#download The link at the top of that page works!

[@josuearana8756]

@@GadgetUK164 I have another question I use only one bin sp1 Buy when I try to check doesnt made anything. I hold D and start and doesnt work. O need to use both baile de MI in the card? Or Game? Regards

[@ericsalidbar1693]

Do you still do mvs board repairs?

[@GadgetUK164]

I have a 2 slot repair video coming up in the next week or two, and I have a few 1 slot related videos coming up too. I cannot do customer repairs though!

[@gibbo9089]

Suffering with a cold?

[@GadgetUK164]

I suffer from immune system problems, so almost every other day I can sound like I am coming down with a cold lol =D

[@jeromepader8940]

Can you help me i have the same problem

[@GadgetUK164]

I cannot do customer repairs sorry!

[@bl1gh7y]

Can you recommend anyone in UK that would look at a AES that won’t run a Terraonion sd pro? All original carts work perfectly and I know the sd pro works perfectly in other systems, just not mine anymore. It used to work until about a month ago. I’ve cleaned all the cart pins bought a beefier psu, changed the big cap by the power switch and the regulator, still no difference. I see no trace rot anywhere either, can I use a diagnostic bios on a aes? It self tests with a blue screen without a cart in it.

[@tongshan8054]

Hello! I follow all your videos! I recently got an AES and got corrupted graphics. Several zeros on the screen including in the diagnostic bios. I'm trying to post on the forum www.neo-geo.com but I'm still not allowed.

[@GadgetUK164]

I cannot help with the forum, but if you can upload some photos of the screen somewhere (or a video on YT), I can take a look to see what I think?

[@tongshan8054]

Thank you very much! 1º - Corrupted graphic using KOF94: kzbin.info/www/bejne/eZXde56khMmFi7s 2º - Using the diagnostic bios: kzbin.info/www/bejne/pKmZYXaXh72GoJI

[@GadgetUK164]

That's quite a failure you have there! Considering the system boots in the 1st video leads me to believe the backbone of the 68K is OK - ie. CPU is booting from ROM, able to run code, use RAM etc. Do you get sound out of interest? The graphical issue could be LSPC or B1 related - have you inspected for broken traces around those chips? The other possibility in relation to those chips is perhaps a missing clock from the D0. But I think its safe to assume that you don't have a problem on the 68K side.

[@tongshan8054]

@@GadgetUK164 Thanks for the answer! I fixed that, it was a broken trace near the cartridge slot.

[@StRoRo]

You need to take a break now.

[@GadgetUK164]

LOL! I've been telling myself that all year lol!