JJAMMA to PCB questions

wxforecaster

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I have a stack of boards in need of repair and I'm sick of trying to work on them in game. So, using a bunch of spare buttons, lumber, a VGA adapter and a purchased JAMMA harness, I decided to wire up my own bench test rig. DONE!

Now I'm trying to create some JAMMA to PCB adapters to get this going. First up, Midway Bump n Jump.

Two questions:
1.) The JAMMA harness has a single sync wire. The BnJ PCB has a H/V sync. Do I just tie them together and call it good?

2.) The BnJ video edge connector also has a wire that the schematics label as -SENSE. What does this go to?

Thanks in advance!
 
I have a stack of boards in need of repair and I'm sick of trying to work on them in game. So, using a bunch of spare buttons, lumber, a VGA adapter and a purchased JAMMA harness, I decided to wire up my own bench test rig. DONE!

Now I'm trying to create some JAMMA to PCB adapters to get this going. First up, Midway Bump n Jump.

Two questions:
1.) The JAMMA harness has a single sync wire. The BnJ PCB has a H/V sync. Do I just tie them together and call it good?

2.) The BnJ video edge connector also has a wire that the schematics label as -SENSE. What does this go to?

Thanks in advance!

How are you going to work on them if you cant even get them to sync???? I would think if you can fix a pcb you can easily get them to sync.
 
Valid question, but it takes me a minute to type here, and a lot longer than that to have to solder/desolder/resolder again when I'm guessing. Sorry, I haven't used these VGA adapters before. Perhaps a proper response would be useful to multiple people who DON'T have PCB repair experience

Good grief, some people take more time to type snarky comments than to actually either be helpful or move on. Hopefully your life issues get resolved. Good gaming.
 
I don't have an answer for your VGA sync issue, but the best advice I can give for your test bench is do not use a VGA converter. You want to use a rgb monitor that will accept the 15k video signal from the game board directly.

Otherwise you will find yourself working on a board where you can't get an image/sync, but are not sure if the board is the problem, or the VGA converter.

A 19" arcade monitor does take up a lot of space, but you can also use a 13" cocktail monitor. Several KLOV'ers also use old Commodore rgb monitors, although they are getting harder to find.
 
I use a Sony PVM8045Q 8" RGB broadcast monitor, they are fairly cheap and take virtually no space.
 
I use a Sony PVM8045Q 8" RGB broadcast monitor, they are fairly cheap and take virtually no space.

That sounds like a perfect size for a test bench. I'm currently using a 13" Apple RGB monitor, I'll have to look for one of those Sony 8" units.
 
The only thing with the 8" ones is that minor graphics glitches (some pixels missing etc) are very hard to see. Other than that, they are perfect and (at least the one I have) has an audio jack ( I believe I have to use a line-in audio adapter)
 
JAMMA harness has a single sync wire. The BnJ PCB has a H/V sync. Do I just tie them together and call it good?

what I do is try it one way and if not then I try another way till I get it
same with the rgb converter

now I do it with it on instead of turning it off everytime I try a new wire configuration
 
Some great responses here, and valid points about using an original tube monitor. Thank you all.

Anyone able to answer my second question? On the bump n jump PCB there is a -SENSE line that runs from the video board back to the power supply. I cannot find anything in the schematics or discussions on what the -SENSE line is/does, and if it is necessary? There was a post above to a pre-made adapter, but since I had the parts and wire, I opted to solder my own. I'm just curious where to connect this input (?) to on a JAMMA harness if it's necessary.
 
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