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OK I solved the video issue on my arcade monitors, it turns out they left video ground (pin 14) unconnected on this PCB.

By running a wire from ground to the JAMMA edge this allows the game to function properly in my case.

CicxDaF.jpg
 
I've seen the two versions. The SOIC sound ROM I think is the sample memory.

There are spots for a few ceramic bypass caps, but still not enough...

It is nice that that later revision adds a keyed JAMMA edge.

Your PCB likely won't sync or work because most cabinets (rightfully) do not tie video ground to ground. Despite this PCB being a later revision, the problem is simply because video ground is floating. Tape off the actual JAMMA edge except the inwards tip of it, and solder a wire to ground. Video will be restored.

His talk about jamma pin 10 is nonsense, but I can say that this later revision has slightly distorted audio. Perhaps a preamp's gain is too high. I have one of these boards as well.

EDIT: Ack, didn't see the page jump - you've already solved it.
 
I suspect the audio issue is due to speaker + and - pins being switched on the JAMMA edge. It works fine on a cabinet, but there's no sound when using a supergun.

I'm going to try switching speaker + and - pins using a JNX Atlas adapter so I don't have to add any additional mods to the board to give it a try.

Will report back and confirm how that goes after this weekend. 8)
 
I confirmed that swapping the speaker + and - pins fixes audio when using a supergun.

To make this nice and easy I used a JNX Atlas from @XianXi:

8Zbw2Zb.jpg
 
Sounds like a supergun that uses the positive speaker terminal with reference to ground :/
 
I confirmed that swapping the speaker + and - pins fixes audio when using a supergun.

To make this nice and easy I used a JNX Atlas from @XianXi:
That's kind of what I suspected, the same thing is with the Asura Blade and Power Instinct, they have speaker + and - mixed up from the factory. The supergun only uses the speaker + (the speaker - is unused).
 
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OK I solved the video issue on my arcade monitors, it turns out they left video ground (pin 14) unconnected on this PCB.

By running a wire from ground to the JAMMA edge this allows the game to function properly in my case.
In case it is helpful for anyone, the orientation of the BASE and TEXT ROMs are as follows:
I just got one of these PCBs in, thanks for info on fixing these issues! I wonder if there's a clean way to invert the audio pins without using an external adapter. I also noticed the volume knob functions backward and the sound is kinda bad, there's a substantial hum and the audio overall seems muffled.

how bad was desoldering the text and base ROMs on this one?
 
I just got one of these PCBs in, thanks for info on fixing these issues! I wonder if there's a clean way to invert the audio pins without using an external adapter. I also noticed the volume knob functions backward and the sound is kinda bad, there's a substantial hum and the audio overall seems muffled.
how bad was desoldering the text and base ROMs on this one?
Sure thing! You could do the same audio mod by following the two audio pins, cutting tracks and swapping them around on the PCB with jumper wires without using an adapter. The audio/hum might sound better once you swap the audio pins around.

Just to be on the safe side, I cut the legs on the text and base ROMs first but desoldering actually wasn't bad in my case - though I seem to have a later revision and better built board than some others have received.
 
I have the newer "Red Sun" style PCB like you do. I added some fresh solder to the Text ROM pins and they all desoldered beautifully. removal was quick and the chip basically fell out on it's own. I think the paper-thin traces really helped my desoldering iron get heat all the way through the hole.

Those WinBond chips are re-writeable and quite nice so I just dumped the original text data and then wrote back over it.

Unfortunately the Program ROM that @Hatsune Mike posted back in post #3 isn't working for me. it boots to a static screen of garbage when running that ROM. swapping back to the original bootleg program Rom works fine.

Just for my sanity I should be replacing the 27c800 right next to CPU with "sys" silkscreened under it, correct?
 
Excellent. Let us know how the audio fix goes. My board also has a bad hum that's audible when the music stops.
 
I have a few of these that need minor repair that I'm accepting I am never going to find time fix; if anyone wants a smokin deal on three PCBs let me know.
PM sent, if these are the ones I can turn into BG easily.
 
I have created a hack that mitigates the hardware problems with this PCB, so that the original Battle Garegga game plays on it without issues (misaligned background layers, background updates lagging 1f behind the sprites)

github.com/mikejmoffitt/bgaregga-bl-fixes
any chance this patch will work on the Type-2 version ROMs?

I figure if both can be made to work I could throw a 27c160 on there and switch between the two.
 
What is the Type-2 version? Both PCB revisions are interchangable from a software perspective if that's what you mean.
 
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