K7000 - Vertical hold problem

[darryldale]

I'm looking for some help guys. When it comes to electronics (wiring, etc...) I'm a noob but pretty tech savvy. Here are three posts I made over on a smaller canadian forum and I'm looking for some feedback:

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POST 1:

OK, so I picked up a MK2 cab that I've been working on.

The guy I bought it off of said he wasn't sure if the original board worked (it's still inside) but had converted it to a mame box using an ArcadeVGA 3000 and a J-PAC.

Seemed to work ok but it was an incredibly slow computer he used so I bought a faster one and installed an ATI 4350 running the crt_emudrivers.

Everything worked great and I fired up the cabinet and then turned on the machine. The boot screen / windows logo are garbled because the computer is not spitting out a 15 hz signal at boot until windows starts.

Windows starts up and I can see the desktop and all is good EXCEPT the vertical hold just does not stick.

This cab has a vertical hold pot on the front under the control panel and although I can tweak it it won't "stick" and the best I can do is get it to do a really slow roll.

I unplugged the new machine and plugged the old one in and same issue. A very slow roll.

Any ideas?

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POST 2:

I have come across a couple of threads online that talk about confirming that the synch wires are hooked up correctly. The problem is I'm such a noob that I have no ideas where the hell those wires even are lol.

http://forums.arcade-museum.com/showthread.php?t=309878
http://forums.arcade-museum.com/showthread.php?t=110851

Anybody point me in the right direction?

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POST 3:

OK, I'm making progress (I think) and hoping for some feedback.

According to the j-pac documentation I see the following:

red = pin 12 component side
blue = pin 13 component side
video ground = pin 14 component side
green = pin 12 solder side
composite sync = pin 13 solder side

I can see five wires going into those spots in a bundle that then go up into the monitor. On the monitor chassis I see the following pins according to the docs as follows:

red - wire from red on jpac goes here
green - wire from green on jpac goes here
blue - wire from blue on jpac goes here
ground - wire from video ground on jpac goes here
+v sync - EMPTY
+h sync - EMPTY
ground - EMPTY
-v sync - EMPTY
-h sync - wire from composite sync on jpac goes here

Everything looks good based on what I found at this link:

http://arcadecontrols.com/BBBB/sync.html

It had the following paragraph:

There are exceptions to everything & the Wells-Gardner K7000... along with some Hantarex monitors & quite a few of the newer imports... only require one feed of a composite sync output bd such as the Pac-Man, hooked up to the negative horizontal input post with no signal at all on the vertical sync post! In fact, hooking up the composite sync to the vertical post will nearly always cause your pic to jump, jiggle or otherwise mess up!

So basically I'm assuming that I need to check all the connections from the composite sync on the jpac to the -h sync on the monitor.

That sound about right?

[big10p]

Someone in the GroovyMAME forum would probably be able to help you sort this.