6 slot MVS troubleshooting (was No sound in Aero Fighters 2)

[driph]

Hey all, fairly new to the Neo-Geo world so I'm just starting to learn the ropes... got a 6 slot in a mini cabinet up and running, and while pretty much everything plays well (after a good cleaning), I can't get the audio to work on my Aero Fighters 2 cart. Is there something in particular I should look for? Would images of the cart boards help?

 

[Jag-Master]

Post some pics and clean the board again and don't forget to clean the slots as well. Does audio work for any of your other games?

 

[driph]

Yep, cleaned both the board and slots, and audio works with other games just fine. My 6 slot is a bit finicky, but I can't get audio working with this title no matter what slot it's sitting in. Here's a pic of the boards:

 

[chris1]

What kind of cleaning method are you using..?

Sometimes you have to go into the deep cleaning methods..

how does the game feel when sliding into the mobo..Real tight or does it slide in smooth..

Whenever games I get are dirty they slide in too tight and I know I'm going to have issues as I always do..
Once I clean the game real well it slides in smooth..

Also if the carts boards are being pressed on too hard by the shell warping them you can have sound issues

Not sure if clearing the back up ram cart memory
will help..

 

[driph]

I cleaned it based on the guides on hardmvs, just went over the contacts with an eraser and tested the cart again... everything plays well enough, just no sound.

 

[Xian Xi]

On the CHA board check the soldering on both the S1 and M1 chips and make sure there are no cracked solder joints.

 

[driph]

They look fine, would it be worthwhile to reheat the joints and see what happens?

 

[Xian Xi]

Yes reheat them, sometimes those joints crack and you can't really tell. If the joints aren't shiny I would desolder them and apply new solder.

Also make sure you play the game in case the sound is turned off in attract mode.

 

[driph]

Hmm, reflowed the joints, and still not getting any sound (although I did have a particularly good game while testing it).

Is one particular chip responsible for sound on these boards?

 

[Xian Xi]

I believe it's the M1 and the S1 is for SFX but I could be wrong. Make sure you check the pins that they don't have a broken trace.

 

[driph]

Aside from those scratches you can see in the left side on the photo above, everything looks to be in great shape, potential suspect areas have continuity, etc. I wish I had a schematic of this thing or something, so I'd know exactly where to look, or which chips to replace.

Hmm, I'll keep digging into it.

 

[Xian Xi]

make sure there are no cracked solder joints on everything

 

[driph]

From http://www.tiptonium.com/neogeo/projects_chipdefinitions.htm:

The chips that begin with C are the chips used to store the graphics or sprites.

Chips that begin with V store the various sound samples.

The P chips contain the actual game code.

The M1 chip is the controller for the sound chip.

The S1 chip is used to store fonts, the game logo health bars and other game details.

 

[Xian Xi]

So I hope you used that info and checked the V chips.

 

[driph]

Aye, and reflowed the joints just to be sure. Game plays beautifully, just without sound.

I wonder if it's possible that I've got a bad chip? Does anyone burn replacements?

 

[driph]

Interesting update.

One of the local Neo-Geo guys (thanks, Dinodoedoe!) was nice enough to let me test it out with his machines, and the cart works just fine, with audio. We exchanged Aerofighters 2 carts, I gave him my US version and took home his JPN Aerofighters 2 to see if there'd be any difference... unfortunately, the difference was that my 6 slot doesnt even boot up his Aerofighters 2 cart, it just sits at the crosshatch (I'll dig more into it tomorrow).

The rest of my games play fine, although I only have 5-6 carts to test on it. Is there something that Aerofighters is doing that my mobo just doesn't like?

 

[Xian Xi]

Looks like your 6 slot mobo is picky. This is a common problem with 6 slots. Put a cart in only slot 1 and boot it, if it plays properly then add a cart to slot 2, if they both play fine then keep adding until you either encounter a problem of they all play fine. You may need to switch some around if one doesn't boot. Find a combination that will.

 

[chris1]

also

Try clearing the back up ram cart memory..
Also your power supply might be a little too low in voltage..Maybe the Aero Fighters 2 games are making the mobo work harder..

 

[driph]

Also your power supply might be a little too low in voltage..Maybe the Aero Fighters 2 games are making the mobo work harder..

Yup, at channelmagic's suggestion I tested the voltage, and it's a bit low under load (4.86).. as the PSU isnt the sort that can be adjusted, I'm on the lookout for a replacement to swap in.

 

[driph]

Just to update everyone here (I've got two tech threads going, one here and one at klov), here's the latest:

Okay, new power supply, and after bumping up the 5v a bit I can get the additional JPN Aerofighters2 I borrowed from a friend to boot up (unlike my US cart, I couldnt even get this one to get beyond crosshatch before). Still the same problem, no sound.

Where do I measure the voltage at the top board?

And additionally, what is the JP1 pin for? It has a connector on the top board, but is blank on the bottom.

 

[driph]

Okay, for anyone in the future that comes across this, JP1 is the voltage connection between the top and bottom board. As far as I know, it's only on the 6 slot.

Unfortunately, connecting the two didn't resolve things, so I'm at a loss as far as what to do next.

 

[chris1]

I'd take the carts boards out of the carts shell and put them in the mobo ..making sure that they put in facing the right direction etc..
This way you know the two carts boards are making contact in the mobo and not being forced into a position by the carts shell

Also,you could position the two carts boards at different heights to find different contact points..

Other..Pull the cart up out of the mobo slightly before powering up to make the carts connectors touch at a different spot..

Have you cleared the back up ram memory as it can cause all kinds of issues..


For cleaning:
I use red industrial SCOTCH BRITE and 91% alcohol..going over only the connectors gently to make them shine and cleaning off the crap with the alcohol..I've been using this method for many years..I've fixed numberous MVS carts sold to me with no sound or graphic issues using this cleaning method.
If a carts connectors look yellow it's no good for me..they have to shine..otherwise I have issues with my MVS,..or NES,SNES etc.

 

[driph]

I'd take the carts boards out of the carts shell and put them in the mobo ..making sure that they put in facing the right direction etc..
This way you know the two carts boards are making contact in the mobo and not being forced into a position by the carts shell

Also,you could position the two carts boards at different heights to find different contact points..

Other..Pull the cart up out of the mobo slightly before powering up to make the carts connectors touch at a different spot..

Have you cleared the back up ram memory as it can cause all kinds of issues..


For cleaning:
I use red industrial SCOTCH BRITE and 91% alcohol..going over only the connectors gently to make them shine and cleaning off the crap with the alcohol..I've been using this method for many years..I've fixed numberous MVS carts sold to me with no sound or graphic issues using this cleaning method.
If a carts connectors look yellow it's no good for me..they have to shine..otherwise I have issues with my MVS,..or NES,SNES etc.

Did all of those, cleaned the hell out of the carts and slots, put the cart in bare, etc etc... even tried two different Aerofighters2 carts, one of which worked fine just hours before in a 4 slot.

Unless it works when I plug the board into another cab, I'm chalking it up as personal issues between the 6slot and Aerofighters2. :/

 

[Dinodoedoe]

Okay, I traded Driph his 6 lot board for my 4-slot. Traded one headache for another. The only issue i have with this cab is that the forth slot will not display clearly. I have green vertical lines through out the monitor BUT ONLY on that slot. I've cleaned my carts and use contact cleaner for that slot. Is there anything else I can do to fix this problem??? What can cause just the one slot to go bad?

 

[chris1]

Okay, I traded Driph his 6 lot board for my 4-slot. Traded one headache for another. The only issue i have with this cab is that the forth slot will not display clearly. I have green vertical lines through out the monitor BUT ONLY on that slot. I've cleaned my carts and use contact cleaner for that slot. Is there anything else I can do to fix this problem??? What can cause just the one slot to go bad?

I think a Broken Trace..