Blast City Rewire

[notsonic]

This probably won't be that interesting since all I've done is make my Blast City back to original, but here we go.

I have a US Bass Fishing Blast City that was gutted and rewired by the previous owner. I also rewired it twice. In its most recent incarnation it was more or less like a US woody Naomi but with a Model 3 power supply, I redid the control panel area with Amp connectors, and added a new sound amp. I never really planned on going full original wiring. I had a power supply and IO board forever but never bothered to look for a cabinet harness. Then when I was going through my things I found a brand new OEM 001 loom and decided I had to go for so I could finally have another Jamma cabinet. Somehow out of 6 cabinets I've really only got one free for Jamma.

So here's the before:



Continued in next post for picture limit.

 

[notsonic]

First I removed just about everything. Then I realized to connect the coin meter I would have to split the cabinet. Split the cabinet might as well be step 1 if you're doing anything with a Blast City I swear. Getting to the coin meter is even worse since the front half has to be separated from the bottom, so the monitor had to come out too.



After that I put in the power supply. I'm still missing the bracket that holds the power supply connector.


And then the IO board:


Front panel area:


Almost done with the Naomi back in and 001 loom:


The best part of a US Blast:

 

[notsonic]

I'm basically done but there's still some loose ends.

I need the monitor connections bracket and the power supply harness bracket. I'm going to attempt to 3d model and print these but I haven't done cad since college and I don't have the originals to measure.

I need to make a monitor harness (600-6738-07), AC wiring harness (600-6738-10), and coin door harness (600-6738-09). I'm just waiting on the connectors for that. I also need the chassis half of the remote board harness.

Finally, I'm not sure if I've got everything routed 100% correctly, especially in the front panel area. If anyone has any pictures or feedback I'd appreciate it. Also if anyone has any suggestions for orienting a Naomi and the Jamma i/o better I'd appreciate that too. It's kinda a tight squeeze right now.

 

[notsonic]

I was able to model and 3d print a replacement mounting plate for the monitor connectors and made a harness based on pictures.


So far so good. JAMMA games look great, the monitor isn't shocking me, the sound amp even works.

The only problem I'm having is that VGA from Naomi, over a ~6ft Sega VGA cable, into the Sega JAMMA I/O, through the 001 loom, cabinet I/O, cabinet harness, and finally monitor harness is causing some ghosting and interference. I'm gonna try swapping the JAMMA I/O with another one. If that doesn't solve it I'll try a shorter VGA cable. And if that doesn't solve it, I'll just go VGA directly into the monitor like I used to. It's a little less convenient but it's better than interference. My JAMMA harness has a ferrite thing on the video, and I haven't seen any other kinds of shielding in pics, so I don't think I'm missing anything that's supposed to be there. I have the VGA port disconnected from the monitor chassis too.

Not sure if it shows up well in the pic but there's ghosting around the naomi logo and some shadowy vertical lines the height of the screen to the left of the N.

 

[kikaso]

Have you tried ferrite cores? I had a similar issue with a NAOMI and adding ferrite helped a bit but didn’t solve.

Slick mounting plate

 

[notsonic]

I tried a PC VGA cable with built in ferrite things on both ends, it didn't do anything. I also tried wiggling different parts of the wiring around and the pattern didn't move.

I also tried Atomiswave which puts out VGA on the JAMMA edge. Almost exactly the same pattern, so it's not the Naomi, VGA cable, or Sega JVS/JAMMA I/O.

Do any of the caps on the Blast City cabinet I/O board interact with the video? I could try to recap that thing. Otherwise I think I'll just go back to the VGA cable direct to the monitor.

 

[notsonic]

First try on the power supply bracket. Almost got it. I'm printing a new version now to fix the top hole spacing and to make it 2mm thick overall.

Also you can see the replacement I made for the 600-6738-10 harness. It's exactly the same as the door switch bypass.

 

[notsonic]

Got it right on the second try! I bumped the thickness to 2mm and fixed the screw holes. Harness fits nice in the square cut out and all the screws line up. Power supply docks nice and smooth, no binding. I'll post the stl in the 3d models section.



Also I messed with the video a little bit. It seemed like by doing nothing, some of the ghosting was gone but still noticeable on the boot screen. I ended up just going direct VGA again, no more ghosting. The vertical lines are still there but not as bad. Maybe they've always been there.
Also while you can use VGA without disconnecting the front input, it's a little dim. It's not too obvious until you disconnect the front video connector, then you realize it's night and day. I'm pretty sure it's switching impedance.

I also wired up the coin door.


Other than cosmetics, I think this thing is finally done.