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So I bought this PCB and I trust that the seller sent it working, as he sent me a youtube of it, however it's dead now, so either he's really being dishonest (not likely b/c of the video and his really good eBay feedback), or something happened during shipping, or maybe the caps are just old and it was time?

So first, I plugged into HAS v4 with proper 5v power to a CRT TV. Game worked, but image was very faded. It looked like the contrast was up too high. I adjusted the HAS color knob, to no avail, so I turned it off to test again later.

Next, plugged into my Dynamo JAMMA cab which runs a few of my shooters right now. Image came up for a second, then dead, no screen, no music.

Finally, I used the HAS and an OSSC to my LCD TV. Nothing. I push the voltage up to 5.1v, and it comes up briefly before freezing and when I powered down then back up again, it's giving "no sync" on the OSSC.

I've then tried on two other JAMMA cabs, with nothing.

So, the seller, wants me to up the voltage to 5.2 and 5.3. This seems very hight to me, as most games work fine at 4.95 (where I usually keep my HAS). I don't think increasing voltage is a good idea. If I do go down that route, what is too high?

Second, it has two photometers on the PCB. Usually I don't mess with these unless I know they are volume, but I don't see a clear marking on the PCB. Could these be used to adjust anything?

Could it just be a bad series of caps? The JAMMA edge connecter isn't the best looking, but I cleaned it pretty good and it seems to be ok.

Thanks guys. The seller is in another country and I'd like to avoid shipping back.
 
Hello,

Bad news for your game :(

First, look the pcb for see if bad trace, or other visual problem...
Try to look the connectors AB board and look the eprom ( deconnect / remove and reconnect / replace ).
Look the P-rom or other components on socket (if legs black, clean them).
Dump your ep-roms /Mask-roms and look if crc match the dump on mame.

After that the pcb need more investigations with shematics....

Good game and music funny ;) Hope you can save it :)
 
Thanks! Any idea about the two photometers and what they do?
 
Generaly, one for music and the other for sample.
 
Potentiometers, not photometers :)

You can find the manual for Rabbit Punch on KLOV. VR2 controls background music, VR3 sound effects.

Anyway, try reseating the roms, then upping the voltage to 5.2 and finally looking for any obvious damage on the board. Not a whole lot more you can do with a basic skill set after that. Then it's either a case of sending it to someone or to start learning the ropes of PCB repair.
 
D'oh, autocorrect b/c I don't know how to spell potentiometer LOL!

OK, I'll try upping the juice after I re-seat everything.

I assumed (probably incorrectly) that the old looking caps are a culprit, but we shall see. I will have to buy some nice tools and start learning nem!
 
Just looking at pics of the board, it looks like the caps are there mostly for audio.

It's a double board PCB, right? Make sure the connectors are firmly seated. That's a likely culprit.
 
OK, so I took off ALL socketed chips and ribbon cables. Cleaned everything and plugged it back up... and nothing.

5.2v Nothing.
5.1v Nothing.
5.0v Nothing.
4.9v WORKS GREAT!!
4.95v Nothing.
4.85 WORKS GREAT
4.8v Nothing.

WTH? This is the first game that has been THIS picky about power and underpowered at that. Is this normal or does this indicate a problem I should be looking for?

Also, with the HAS, the screen is still very washed out. On my JAMMA cabinet, I'm able to adjust the monitor to make it darker and make it look OK, but the video output seems very different. The HAS knob adjust darker, but cannot dial it in on my CRT TV.

Anyway to fix this to work with my HAS or is this just an unusual PCB? Or is something still wrong with it?
 
IMG_7386.jpeg
 

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You can see in the image above, the background should be black like the edge of the monitor, but instead it is grey.

Any ideas?
 
I'd recommend replacing the capacitors. That may resolve both the issues of the dark display and the pickiness over the power. I've had boards that displayed dark and then a cap replacement brightened them right up.

If the new caps don't make a difference, you can at least cross them off the list of potential culprits - it's never a bad idea to replace old caps IMHO.
 
I wonder if there is some common fault with this PCB, or is it the supergun compatibility issue, because I googled and found pictures that look washed out, too - https://www.worthpoint.com/worthopedia/rabbit-punch-rabio-lepus-jamma-pcb-161492357 (notice the black edges of the monitor).

Do I understand it correctly that it's the same on the cab and you just "fix" it by darkening the monitor?
Correct @RGB even on my JAMMA cab, it is too bright and I darken the monitor to make it look correct.

I'd recommend replacing the capacitors. That may resolve both the issues of the dark display and the pickiness over the power. I've had boards that displayed dark and then a cap replacement brightened them right up.

If the new caps don't make a difference, you can at least cross them off the list of potential culprits - it's never a bad idea to replace old caps IMHO.
Thanks @ShootTheCore, but the screen isn't too dark, it's too bright, as if the PCB is getting too MUCH power, even when I turn the PS down to 4.85v.

Of course, it could be a cap (or something else), but I guess for now it works. I'm going to play through it (at least as far as my skills take me on a $2) and see if the board freezes up. On power more than 4.95v it seems to freeze pretty quickly (just running the demo).
 
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