Video unstable on consolized MV-2F

Hello

I'm having an issue with crazy jumpy video signal vertically, so it moves from bottom to top.
There is no sound issue, it's clean
There is no horizontal issue, colors are crisp and correct, and the bios/games just boot up fine.

I bought this consolized slot from a guy here about 5 years ago, and yadi yadi yada for the last year and a half it has been sitting in a cardboard box (so protected from dust). Since i had some alone time this summer i got it out of the box.

So far, i've opened it and tried to use some air can, look at the soldering in case something was loose, but can't notice anything... It has always been taken care of, no smoking and dust protected after use, so the board is still quite clean.

The unibios in it is v2.1 (it's written v1.3 on marker with a 2.1 sticker on top), is there any chance that the bios has gone bad?

Of course i checked on 2 TVs (one is old CRT, and the other is a panasonic 32" lcd) and the effect is the same. The RGB cart and some parts of the motherboard have been 'cleaned' with a special product (Kontakt LR) and no change.


Any interested guess would be severely appreciated
Best regards.

Have you tried a sync cleaner?

I made a video with the iphone:

http://www.youtube.com/watch?v=5cPZAhAqr4U

---
Is that a proper sync cleaner?



Not sure i would know what to do with it

Yeah probably worth a try.
You could also try a cap on the sync line... but might be worth just getting one of the jrok sync cleaners (like on JNX).
It will come with a wiring diagram, but essentially you hook up +5V and GND to it and then feed in the sync from the mvs board into the input, and then take the output sync to your encoder/etc.

How are you running video? Through an encoder or just RGB?

Hi,

xiao_haozi said:

You could also try a cap on the sync line... but might be worth just getting one of the jrok sync cleaners (like on JNX).

Click to expand...

You can also try, to change or put a resitor in the SYNC line, change it for a 3k resistor, the resitor must be put before the cap in the line like this scheme.

SYNC----->Resitor------> +Cap- ----->to TV

Saludos

Well, i'm back with board pics, this might help you to understand more of this...

Why are the signals tapped there? There's barely anything to solder to. Check the sync wire if it's even soldered on.

Sefer Halilović (Xian Xi --if you refuse to deal with him over a name change a mod will stab*;3046785 said:

Why are the signals tapped there? There's barely anything to solder to. Check the sync wire if it's even soldered on.

Click to expand...

Maybe they like a challenge...

Sefer Halilović (Xian Xi --if you refuse to deal with him over a name change a mod will stab*;3046785 said:

Why are the signals tapped there? There's barely anything to solder to. Check the sync wire if it's even soldered on.

Click to expand...

I've checked against the tutorial on jamma nation for a 2 slot:
http://www.jamma-nation-x.com/jammax/cmvs2slot.html

And for the sync point (purple) indicated in the tutorial, there is nothing soldered on my board.
But this board has worked fine on the same TV that it now has a problem with (the CRT one), so it has to be something else.

Izsomean said:

I've checked against the tutorial on jamma nation for a 2 slot:
http://www.jamma-nation-x.com/jammax/cmvs2slot.html

And for the sync point (purple) indicated in the tutorial, there is nothing soldered on my board.
But this board has worked fine on the same TV that it now has a problem with (the CRT one), so it has to be something else.

Click to expand...

Well if sync isn't soldered anymore, maybe it was before and has just come off....
Reattach and see what you get.

Treating MVS differently from AES makes no sense.

Izsomean said:

I've checked against the tutorial on jamma nation for a 2 slot:
http://www.jamma-nation-x.com/jammax/cmvs2slot.html

And for the sync point (purple) indicated in the tutorial, there is nothing soldered on my board.
But this board has worked fine on the same TV that it now has a problem with (the CRT one), so it has to be something else.

Click to expand...

The sync on your CMVS is soldered right after the connector edge instead of the 470ohm resistor. It's the same signal BUT the small plate-through on the connector edge has barely anything to solder to so the wire might have come loose. Check if it has. If it has I would solder it to the leg of the 470ohm resistor instead. In fact if you have the time resolder all the video signals to the resistors instead.

Sefer Halilović (Xian Xi --if you refuse to deal with him over a name change a mod will stab*;3046874 said:

The sync on your CMVS is soldered right after the connector edge instead of the 470ohm resistor.

Click to expand...

or instead of a more appropriate place...

LOL, yes. In simpler terms.

are you sure you got what I mean?

MKL said:

are you sure you got what I mean?

Click to expand...

I'm guessing you prefer the source?

Sefer Halilović (Xian Xi --if you refuse to deal with him over a name change a mod will stab*;3046889 said:

I'm guessing you prefer the source?

Click to expand...

I prefer to treat MVS and AES the same way and where do you tap sync from on the AES? Definitely not from a 470ohm resistor.

Sefer Halilović (Xian Xi --if you refuse to deal with him over a name change a mod will stab*;3046785 said:

Why are the signals tapped there?

Click to expand...

those spots were there and albeit a bit small looked as if they were made for being soldered to. they were useable and the result looked much cleaner than soldering directly to the jamma edge. there's no other reason, really. keep in mind that consolized mvs boards weren't nearly as common as they are now when i built this thing many, many years ago. might have been in late 2003 or 2004. i was shocked to see how clean it is, actually.
also, i didn't just solder the wire to that spot. i filled that tiny hole with solder first and the connection seemed plenty strong.

picture looked perfect on my old sony crt tv, which unfortunately died back in 2007.

fun fact:
i bought (ebay) my first mvs board back in late 2001, because i couldn't afford metal slug and turf masters for my ngh. in fact, i couldn't really afford anything at the time. i didn't have a jamma connector to build a supergun. didn't even know where i could have gotten one from, so i soldered right to the jamma edge and mounted the needed sockets as well as the power switch to the metal cover of the 2 slot instead of a separate box. when i got to the point that the cover was painted and everything was stuffed underneath it, i decided to post a picture. now i don't know what others might have done before i joined but judging by Tonk's reaction it might have been the first of it's kind that was mentioned around here. since then i tried different things and what you see in these pictures is part of the progression. i was never even taught how to solder.

MKL said:

I prefer to treat MVS and AES the same way and where do you tap sync from on the AES? Definitely not from a 470ohm resistor.

Click to expand...

On the MVS I do it at the 470ohm resistor and on AES from the sync input pin on the CXA.

Which would be the better place on both? Straight from the LSPC2?

Sefer Halilović (Xian Xi --if you refuse to deal with him over a name change a mod will stab*;3047068 said:

On the MVS I do it at the 470ohm resistor and on AES from the sync input pin on the CXA.

Which would be the better place on both? Straight from the LSPC2?

Click to expand...

Sync input of the encoder = straight from the LSPC2, yes.

Got it buddy. Thanks again.

xiao_haozi said:

Well if sync isn't soldered anymore, maybe it was before and has just come off....
Reattach and see what you get.

Click to expand...

Sefer Halilović (Xian Xi --if you refuse to deal with him over a name change a mod will stab*;3046874 said:

The sync on your CMVS is soldered right after the connector edge instead of the 470ohm resistor. It's the same signal BUT the small plate-through on the connector edge has barely anything to solder to so the wire might have come loose. Check if it has. If it has I would solder it to the leg of the 470ohm resistor instead. In fact if you have the time resolder all the video signals to the resistors instead.

Click to expand...

I've pulled on all the wires but no, the solder is still strong and nothing seems loose.

Another pic of the jamma pins:



So the sync pin are the blue/white wires, right?

@ Supergoose: looks like i'm lucky that you're back

I actually do have a multimeter (simple one, like from school) , if you could tell where to check that'd be fantastic =)

MKL said:

Sync input of the encoder = straight from the LSPC2, yes.

Click to expand...

I've taken a pic of the LSPC2, where would the soldering go please?



( i hope it's not directly on the chip pin, cause i can't do that, wya too tiny for my skill)

BTW, thanks for the help guys!

My posts were directed to Xian Xi and his guide, not to you and your issue. Anyway, this is a shot of my consolized 2-slot that shows where sync (orange wire) is tapped from:

http://a.imageshack.us/img38/3525/2slotsync2.jpg

And here you can follow the path of the sync signal (point 2 is where I take it):

http://a.imageshack.us/img691/9643/2slotsync.jpg

What you should do is check continuity between point 6 and pin 20 of your scart connector (with the cable plugged into the system of course). If there's no continuity, there is your problem. If there is, then it could be that the OR gate in the NEO-IO (points 3 and 4) has gone bad. Here's a couple of threads where the problem was discussed:

http://www.neo-geo.com/forums/showthread.php?t=121136
http://www.neo-geo.com/forums/showthread.php?t=206567

If that's the case, tapping sync from point 2 (i.e. before it's fed into the NEO-IO) is the next thing to do. However, soldering to those vias isn't easy and straightforward, it requires some preparation: the solder mask needs to be scraped off around the hole on both sides, then you need to tin it, then suck the solder out and finally you can put a tinned 28AWG wire through the hole and solder. Problem is your wires are way too thick for this, not to mention that having moving wires soldered to tiny points on the PCB isn't a good thing.

Izsomean said:

I actually do have a multimeter (simple one, like from school) , if you could tell where to check that'd be fantastic =)

Click to expand...

should be good enough.
i would try to check, if all the soldered connections are fine. test the rgb cable, too. maybe it's a problem with the scart plug or the socket in the back of the system.

if it sat for 5 years and wasn't used then there might be a chance that one of the pins is slightly corroded. not sure how likely that is, but i would check that too just to make sure.

MKL said:

My posts were directed to Xian Xi and his guide, not to you and your issue. Anyway, this is a shot of my consolized 2-slot that shows where sync (orange wire) is tapped from:

http://a.imageshack.us/img38/3525/2slotsync2.jpg

And here you can follow the path of the sync signal (point 2 is where I take it):

http://a.imageshack.us/img691/9643/2slotsync.jpg

What you should do is check continuity between point 6 and pin 20 of your scart connector (with the cable plugged into the system of course). If there's no continuity, there is your problem. If there is, then it could be that the OR gate in the NEO-IO (points 3 and 4) has gone bad. Here's a couple of threads where the problem was discussed:

http://www.neo-geo.com/forums/showthread.php?t=121136
http://www.neo-geo.com/forums/showthread.php?t=206567

If that's the case, tapping sync from point 2 (i.e. before it's fed into the NEO-IO) is the next thing to do. However, soldering to those vias isn't easy and straightforward, it requires some preparation: the solder mask needs to be scraped off around the hole on both sides, then you need to tin it, then suck the solder out and finally you can put a tinned 28AWG wire through the hole and solder. Problem is your wires are way too thick for this, not to mention that having moving wires soldered to tiny points on the PCB isn't a good thing.

Click to expand...

Thanks, so i checked for continuity between point 6 and pin 20 and it's there.
But if decide to solder on point 2, i still don't know which wire i should unsolder to put it there, the white or blue one?
An attempt to solder there feels like a dice throw but as a last resort...

About the scart cable, there is some very tiny bit of rust on the scart pins.
i also found this thread with a similar problem: http://www.neo-geo.com/forums/showthread.php?t=175257

Can't find any similar cable on the web, i guess they need to be custom made :/