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Monitor not energizing on a 220v Blast City

Jokerbomb

Jokerbomb

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Hello everyone!

I recently picked up a 220v Blast City and I was told that the monitor didn't work. I didn't know it was a 220v at the time, but when I got it home I picked up a step up converter in hopes that the issue was merely 120v trying to kick this thing over. Well, after getting the converter the monitor still won't energize.

As I started poking at it, I noticed that the transformer in the cab isn't hooked up:

1792866623680.jpeg


I'm guessing this is likely part of my problem, but I cannot for the life of me figure out how it hooks up to anything. There are a couple of things with this cab that lead me to believe this thing was converted to be a MAME cab at some point (There's an IPAC hooked up to all the controls and they spliced a 3.5 mm jack into the audio lines on the JAMMA harness).. So I'm wondering if this is all part of the problem.. Any insight would be appreciated! Thank you!
 
What monitor chassis is actually in it? Personally I'd just start by converting it back to its original wiring configuration, no reason to use a step up when everything in it originally should be using 100V originally. If it's a 220V setup I'd guess it was imported from China at some point.
 
Yeh I’m in uk




Looks like you have the correct iso transformer.

Should be 110v-120v
Normally ..

Shame that transformer don’t have any indication for the input required .but sure looks like the original Japanese one to me
 
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I have a blast city which works perfectly fine with an transformer imported from china. I could give it a look if you need something specific.
 
AeroCity20XX said:
What monitor chassis is actually in it? Personally I'd just start by converting it back to its original wiring configuration, no reason to use a step up when everything in it originally should be using 100V originally. If it's a 220V setup I'd guess it was imported from China at some point.
Click to expand...
From my investigations, it looks like the original Nanao MS-2931 as it has VGA out. It's definitely a 220v setup as both the PS and the Sega labeling both show a 220v label:
1792874655965.png


@1credit - I realized now I should just free this the transformer from the cab itself and see but I think the wiring label is there. I think I'm just a little confused on where it gets connected to the chassis.. or if it gets connected to the chassis at all.
 
st3ncil said:
I have a blast city which works perfectly fine with an transformer imported from china. I could give it a look if you need something specific.
Click to expand...
Would you be able to show me where the iso transformer is connected to? My schematic skills are rusty these days as I'm not entirely able to parse it out from the Blast City schematics I've seen.
 
Jokerbomb said:
From my investigations, it looks like the original Nanao MS-2931 as it has VGA out. It's definitely a 220v setup as both the PS and the Sega labeling both show a 220v label:
1792874655965.png


@1credit - I realized now I should just free this the transformer from the cab itself and see but I think the wiring label is there. I think I'm just a little confused on where it gets connected to the chassis.. or if it gets connected to the chassis at all.
Click to expand...
Dam I would love to swap my 120v with that one !🤣

Buy the way ..
The sound amp is built in with the psu .

That looks well clean also
 
Jokerbomb said:
From my investigations, it looks like the original Nanao MS-2931 as it has VGA out. It's definitely a 220v setup as both the PS and the Sega labeling both show a 220v label:
1792874655965.png


@1credit - I realized now I should just free this the transformer from the cab itself and see but I think the wiring label is there. I think I'm just a little confused on where it gets connected to the chassis.. or if it gets connected to the chassis at all.
Click to expand...
On an original 220v setup, power in is 220v it goes to a 220v to 110v isolation transformer (pictured earlier) and power to the PSU and chassis is 110v.
 
IMG_1322.jpeg

This is transformer what we have in uk.

The Power connector to chassis will be a small 2 pin connector with black & white wires .
Left back corner of the chassis looking from back

Through that stupid little hatch ! 🤣🤣

The sega Naomi does have that advantage that the monitor is fully open once the separate rear cover is removed . No such innovation for blast I’m afraid .. so it’s either through the hatch or remove the whole monitor .

Blast has another
Extra power switch
Round front of the cab . Under the control panel .

Lift up the control panel and look for another power switch .

Here
IMG_1327.jpeg


Also

Safty cut off push switch top left of service door !
( normally tapped up to keep it held in ! )

Cab won’t power up without that switch pushed in .



You might have this door switch?
IMG_1328.jpeg
 
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