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I made a few discoveries this morning.

The jamma harnesses I have been using are not Jamma harnesses. They are 56 pin Mahjong harnesses and are wired completely different. How I was able to get sound and video is a miracle.




@Hatsune Mike was correct about the audio being hooked up to Speaker +- and not aduio/ground.

There is nothing plugged into the FG (Shouldn't there be a green wire?) in the psu.

My Tetris got fried and no longer works on my other cabs.

I noticed the color matching from the Seag 36 pin to the 56 pin were not all color matched and I think its because they were rerouted for mahjong.

I don't know what the better route is at this point: Either re color match the base to the 56 pin or route each wire to the JAMMA from its origin based on the standard JAMMA pinout.
 
The one in your first picture is certainly JAMMA. However, it is curious that it is missing -5V. The second picture looks messy, but also like it is JAMMA. Do you have a harness that is different than these two?

I recommend getting the G-pin for the HIrose connector, which slots into pin 7, so that you are not able to incorrectly insert pins in the future.
 
JAMMA harnesses aren’t always color coded with the wires, particularly if someone made/hacked one. That said, I don’t know if these are from the factory, so I’m generalizing.
 
The one in your first picture is certainly JAMMA. However, it is curious that it is missing -5V. The second picture looks messy, but also like it is JAMMA. Do you have a harness that is different than these two?

I recommend getting the G-pin for the HIrose connector, which slots into pin 7, so that you are not able to incorrectly insert pins in the future.
The top picture is definitely Jamma (from blast city cab) and after following the leads from the 56 pin connector I believe the second is too.

I had my multi meter on the 250DC setting so when I changed it to 20DC I got much better readings.

My volts were 5.12, -5.08 , and 12.08 but still wouldnt stay stable and went .03 variable constantly.

I foloowed each wire from the JAMMA edge to its appropriate Origin and found nothing wrong.

I did find an extra connector coming off the -+ speaker wires connected to nothing

and another 100 AC chopped line coming from the power connector to the monitor.

Also had one of two ground wire connectors going nowhere.




I couldn't test the AC voltage on the PSU for some reason.

I tried white com wires from above as my ground and couldn't get the x2 AC connectors to produce a reading.

There is nothing Plugged into

FG, NC, FG or NC, just x2 AC cords on the connector.

Now all I can see is rolling slanty lines over the CRT with nothing plugged into it?

 
Now all I can see is rolling slanty lines over the CRT with nothing plugged into it?
That's normal. You want to turn down SCREEN on the flyback until just the point where they disappear.
 
With no source plugged in the MS8 tends to do that even with a correct screen voltage. Are you sure you didn't just plug Tetris in backwards to the JAMMA edge?
 
I would be naive to think the problems are gone after this point.

I plugged in Gunforce and there was no buzz, bright visuals or resetting.





I played a much better round of Gunforce and took over both helicopter and jeep and kicked ass. I still died to the boss in 1 token.

I hope my gunforce doesn't go the way of the tetris and still have many questions about grounding the PSU and proper connections that should be followed.

Can anyone else confirm that owns an Aero, that the FG (Frame Ground) is not hooked on their psu or the NG Neutral Ground?

That would be very helpful and possibly stop frying my test PCB's.
 
The Tetris was a bootleg and the dotorikun only features a single color display and joystick control.

I also wasn’t plannning on frying anything.

After following each wire on the JAMMA edge to the source, I am confident I wired it correctly.

It’s the inputs on the PSU that are suspect to me because I want to make sure it’s properly grounded and hooked up.

I’ll take more voltage readings on dotorikun tommorrow
 
Im not saying use it to set the colors, but it's common practice to use a junk PCB on cabinets until you get them where you want... especially since you have fluctuating readings on your psus.
 
@hoagtech, .03v of voltage fluctuation is not really problematic, and at most means maybe it's time to replace the filter caps on the 5V line, after the switching regulator. You likely had such wild variance before because your meter was on a more coarse range. Manually ranged meters often have low-resolution ADCs, so the precision outside of the selected range is somewhat low. Bring it down to ~5.0v, using a less important game (like dottori-kun), and if you are really worried about it then recap the thing.

The lack of FG is not a real problem, and a lot of arcade cabinets do not have a field ground connected to the PSU nominally (e.g. Egret II).

What will feel really good is pulling everything out of the cab, and giving it a really good cleaning.

Edit: Since I have to mail you a PCB anyway, I'll toss in a few G-pin JAMMA keys for your Sega cabs.
 
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Personally I think you've been going about this all wrong. Chopping cords up, frying boards, doing tests before anyone has had a chance to reply. You have wasted so much time.

First order of business was testing it ran after shipping with a crap board like dottorikun.

Then a complete strip down, paint/restore, RECAPPING since they haven't been touched likely since 1988.

That thing is a fire hazard as it is with the dirt, dust, smoke, and feces build up.
 
Thanks for the feedback @Kavas. I’m looking forward to your and @8bitforlife ‘s Aero city arrivals.

I bought the bootleg Tetris for $30 and Dottori Kun sells for $70 as it’s a Sega collectible.

After initial testing. I had to wire in a 6b control harness and wanted to test with my crappiest PCB.
Kun does not have buttons tests.

In order to even look at these cabs I have to commute for 45 minutes to my hydroponic warehouse so my time to get anything done is small.

The board fried because of the Sega base. If you would breath on it, it would warp your picture and create loud buzzing sounds. After bridging it to the JAMMA. I can rule that out as part of the problem. I left 2” wire leads on all parts if I get the hankering for the Sega base repair.

I spent an hour following the 36 pins from the Jamma edge to its origin and feel more confident in fixing the other 3.

Here’s the status of the other 6 cabs

Aero 1 :Locked

Aero 2 : Locked

Aero 3 :No power

Aero 4 : Testing wiring

Blast 1 :Locked

Blast 2 : Super dim

Astro City : Dead on arrival
 
Dottori-Kun is not a $70 PCB. Nor is it a “collectible”. Yaton has had them up (and still for sale) at $20. I even found two for $10 a pop at Highway a few months ago.

That’s all.
 
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Weird. When I looked it up before. sellers were asking more for it but now I cant find it.

I understand your concern for people not breaking pcb's and that is not my intention.

Hopefully my noobness doesn't leave a wake of destruction moving forward.

I am the warehouse now. I will take another voltage reading with kun hooked up.

I would like to know a couple things.

Where is the volume control knob? my speakers very loud.

How do I test the AC voltages on the PSU. I know to place the red lead on the AC line but I cannot get a reading off the com ground like I can my DC voltages.

 
I hooked up the Kun and got the these voltage reading

+5.08
-5.02
12.02

Should I drive up the voltage a bit or are those good readings?



I left it on for 20 minutes and didnt observe any glitching, buzzing or whining and took another voltage reading and it was the exact same.

After feeling better I hooked up Radiant Silvergun on my Multi and beat the first boss.




I'm going to try my luck with my current detector on the dead Aero.
 
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