Problems with a Mega33 Cab

[Domino]

Hellows

I've finaly had the time to start my Mega33 Cab, sadly though all i get on startup is this



Each time I boot up, a different set of pixels is shown.

Anyone has any idea of where to start looking to solve the problem?
According to the previous owner its supposed to run Metal Slug 2.

Here's a pic of the cab itself



Thankful for any help i can get  

[bkenobi]

Looks like the board has a (or multiple I suppose) bad or badly seated rom chip.  It also needs to have the tube adjusted for pincushion.

[Domino]

Would that be the monitorboard or the PCB you're referring to?
Adjusting for pincushion isn't a term I'm familiar with either I'm afraid  

Thanks for helping out  
//N00b on troubleshooting Arcadecabinets  

EDIT: Found out what pincushion ment, however that seems like a small problem compared to the "pixelissue".

[Domino]

Additional info:

I was able to drill the lock today, here's what was inside. MV-1FZ Motherboard?


Any ideas what this is for?


Jumper settings, on boot the little red LED lights up, but no sound what so ever is heard from the speakers



I wasn't able to get any good shots at the monitor, but maybe these will help a little

[Domino]

no one who has a single clue to where the problem might be?

Should i try to get my hands on a Jamma PCB to test?
Maybe another MVS casette?

Any ideas welcome

[Domino]

In need of help here... pretty please 

I pulled out the MVS motherboard and mounted it in my TV Game cab.
After checking that the Compugam -> jamma wiring was correct i booted it up.

In this cabinet the monitor displayed multiple transparent images och metal slug 2 running. (blury transparent in layers on top of eachother, will post pic later)

The game at least seems to boot up fine.

Seems like the big problem is in the monitor then :/
Where do i start with the troubleshooting?

Note: On bootup in the TV Game cab, it displayed Mega33 system, so it seems like the motherboard is the one that came with the cab.


Thankful for any help provided

[Domino]

Here's what i get when the TV Game cab is booted up with the MVS from the Mega33 cab

[mrclean]

The other cables on that harness Red Green Blue (Black for ground) and yellow / White sometimes grey (sync) cables that are connected together are your video cables that go into the monitor, looks like you have a sync issue.


I would read this to identify your wiring being that it's JAMMA :

http://www.jammaboards.com/jcenter_jamma_pinout.html


it could also be a pot on the monitor, such as v.hold / h.hold .. try to tweak with them . That should stop line scrolling and messed up graphics. V.size , Brightness, H.Size, Contrast shouldn't have anything to do with it. They look like little white knobs on the monitors chasi.

[Domino]

Thanks a lot mrclean

Great when someone confirms your suspicions, it makes it a whole lot easier.

I've already spent about an hour checking all the wiring so its correct for Jamma & NeoGeo.
the source of information is hardmvs.com (http://hardmvs.com/manuals/Jamma2NeoGeo4SlotPinout.pdf)

The signal wiring (RGB) is correct, if I'm not completely mistaken the H.sync & V.sync is connected to the same pin.

I'll open up and try to find the monitor pots and see if I can get a correct picture that way first

My memory isn't the best, but I'm quite sure that my sync cables were grey/yellow.

Once again, thanks a lot for the help

[Forces21]

The original problem you reported in the first post, judging by the pictures you show, may be down to the power supply to the NEO-GEO board. I'd connect it back up to the original cabinet and then test the voltages coming from the Harness on the NEO-GEO board. I would suspect an incorrect +5v feed. If this is the case then there is usually a pot on the powersupply to allow you to increase or decrease the voltage. You should aim to get this as near 5.0v as possible. Some boards require a little more (not more that 5.2v normally).

Hope this may point to the right answer for getting your original cab working. Just thought I'd mention this as when you go altering things on your working cabinet you could end up making it not work for any other boards you have (if there is a problem with the NEO-GEO board).

Regards

Forces21

[Domino]

Forces21 Thanks man, that's a real helper

Always a lot easier when you know where to start the troubleshooting.
Mega33 Here i come

[Domino]

Checking the +5 voltage was the key to unlocking this quest

Checking it with the multimeter revealed that when i powered it up there was only 4,03 Volt.
Adjusting the +5v on the board didn't effect the output voltage though

But about a minute later the voltage had increased to 4,30, waiting a couple of minutes seemed to highten the output voltage.
When it reached 4,51volts the Wonderful NEOGEO screen was shown correct

But the joy was temporary, pretty soon a beeping noise started coming from the PSU and shortly thereafter it shut down by itself.

Unplugging and replugging the cab repeated the previous happending.

Seems like my PSU is fairly unstable   Checked all soldering on the PSU board, some damage was found and repaired.
Unfortunately this didn't help med with my problem :/ Which component should i attack first? Capacitors?

[Forces21]

In all honestly the PSU should just be a standard swithching type. I'd probably just say buy a new one.

I'm from the UK and new these cost just about £20~£35 So I'd say about $50.00 max.

Here's one on a German site (Does yours look like this? or is it totally different?)

http://www.arcadeshop.de/Power-Supply-Power-Supply-110W-5/12/-5V_1013.html

If you can take a picture that would sure help.

Cheers

Forces21

[Domino]

I've already taken photos of the PSU and the rest...

Unfortunately those pics are still in the SD-card at home :/
I'll throw up some pictures here as soon as i get home.

It's a simmiliar type that you linked to, there's a swedish onlineshop who offers new PSUs to a affordable price (the same kind you linked to)
http://www.arcadegames.se/prod/A_PWR_S.htm I was hoping to go with (5306) but it doesn't seem to supply -5v.
Therefore i'll probably order (5305), I just want to check the Ampere required by the Mega 33 first.

Will post the pics later on today, Thanks for all help so far

[Domino]

Open up the casket


The PSU from the Mega33 cab


Soldered cables on the underside :/


Proof that it worked briefly



I had another PSU lying from a slaughtered cab, unfortunately it didn't fit the connections of the Mega33

But I've located a regulator that doesn't seem to be factorymounted.
I'll see if a have a spare to replace it with.

[Jack Burton]

That is such a nice cabinet.  Just about perfect for 2p versus play in a fighting game. 

I hope you get it working. 

[Domino]

The PSU had its final nail in the coffin yesterday.

Next up, another arcade PSU.

I'll probably unsolder the connection from the current PSU, then run wires to connect it to the new PSU.
That way i can keep the original connection in the cabinet.

[Domino]

The cabinet is now working perfect

Changed the PSU, pics coming up later

[Domino]

Homemade adapter to enable remounting of original PSU


It's alive (But the Babe playing it isn't ^^)



Thanks to all people who helped me with the troubleshooting

Next up is resoldering the speakercables...