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Neorebel
01-27-2015, 02:07 AM
When I plug in and switch on my cab I don't hear that big 'snap' of it coming on and I get a blank screen on the monitor. I noticed the red light on the power supply blinks for a moment but doesn't stay on as it usually would. I'm assuming I need a new power supply... anyone know where I can get one of these? I guess I can always go back to the original Op that sold me this back when for help too. This is a Jamma cab with a MV-1F motherboard.

Also, anything I should check on my own as far as something easy like a fuse, reset, or busted capacitor? Should I take it apart? Any safety concerns? Thanks in advance!!

Pics:

2234722348

Neorebel
01-27-2015, 08:49 PM
Do you guys think this will be a compatible replacement?

Power Supplies: 15 Amp PowertecUSA Switching Power Supply
Features:
Full 2 year warranty
Built in EMI filter
85% typical efficiency
Short circuit protection / all outputs
Overload protection
100% burn in tested
Computer grade quality
Green L.E.D. "Power on"
Compact size (7" x 1 15/16" x 4 3/8")
Electrical Specifications:
Voltage Power
+5 Volts 15 Amp
+12 Volts 4 Amp
-5 Volts 1 Amp

*115W of continuous power
*115V/230V AC selectable
*U.L. listed

Build Your Order SKU# Name Description Pricing

01-1010 15 Amp Powertec USA Switching Power Supply $23.95 (Each) $22.95 (L/6) $20.95 (L/20)
From http://www.competitiveproducts.com/list_children.php?id=5

Kid Panda
01-27-2015, 08:59 PM
Yep, that will work fine.

Neorebel
01-27-2015, 11:06 PM
Thanks man! Any idea about installing it properly? Have you done this before? I found this guide online and I was just wondering if there were any concerns regarding electrocuting myself or frying the board or monitor chassis I should be wary of, haha...

http://www.aceamusements.us/arcade-video-game-switching-power-supply-installation.html

madman
01-28-2015, 01:40 AM
120V won't fry you. Just make sure the cable is unplugged when hooking it up. Pretty simple stuff, you'll be fine.

Neorebel
01-28-2015, 02:51 AM
Exactly what I wanted to hear, thanks. I'm sure it's not the transformer because the monitor turns on, just there's no startup of the neo geo board.

grendelrt
01-28-2015, 09:05 AM
I would check the 5v voltage at the jamma edge to the mvs board using a multimeter. Even if you replace the PSU you are going to need to do so when you hook up the PSU, don't trust what it's set at when it arrives. You should check it at the harness and jamma edge when hooking up so you don't send over 5v.

Atro
01-28-2015, 09:46 AM
I would check the 5v voltage at the jamma edge to the mvs board using a multimeter. Even if you replace the PSU you are going to need to do so when you hook up the PSU, don't trust what it's set at when it arrives. You should check it at the harness and jamma edge when hooking up so you don't send over 5v.

This.

And you should add up a small voltmeter on that line too while you're at it.
They're dirt cheap at ebay. Easy to install as well.

That'll save you from bad surprises.

Neorebel
01-29-2015, 03:55 AM
Thanks very much gentlemen!

Neorebel
02-03-2015, 10:46 PM
I got the new PSU in there and everything is working fine. Only one oddity - I tested the +5V at the jamma board connector on pins 1 and 3, negative on the ground, positive on +5v (position 3 on the jamma edge) The voltmeter was reading around 2.6v with the dial on the PSU for +5V cranked as far as it goes.

What I ended up doing to be safe is lowering the dial to the minimum point in which the board comes on. I played a few rounds of KOF 98 without any resets or freezing, so I am assuming an adequate amount of power is coming through.

Any thoughts or comments? I figure I'm alright with it as it is...

Xian Xi
02-03-2015, 10:58 PM
Test the +5v level on the chip furthest from the JAMMA edge on the board.

Neorebel
02-03-2015, 11:24 PM
Thanks Xian Xi - where should I place the leads? Should I put the positive lead on the +5V pin on the PSU and the negative lead anywhere on the chip? Sorry, I have no idea...

Xian Xi
02-04-2015, 04:42 AM
Thanks Xian Xi - where should I place the leads? Should I put the positive lead on the +5V pin on the PSU and the negative lead anywhere on the chip? Sorry, I have no idea...

Negative lead on the ground pin of the chip and positive lead on the VCC(+5v) pin on the chip.

Neorebel
02-04-2015, 12:24 PM
I'm having trouble reading these pinouts - GND is obviously ground, but which would be +5V? Sorry to be a pain, and thanks for your time.

https://wiki.neogeodev.org/index.php?title=Category:Chips

bustedstr8
02-04-2015, 02:48 PM
You check voltage on any 74XXX chip. Put ground on the jamma edge ground and the red on the last pin of the chip (Vcc)

http://electronics-diy.com/schematics/74LS74.jpg

Neorebel
02-04-2015, 03:20 PM
Would you mind circling what those chips might be on this image? I feel so inept

22582

bustedstr8
02-05-2015, 12:22 PM
Right behind the edge connector and resistor row are two 74LS273. You can test voltage on pins 10 and 20

Neorebel
02-05-2015, 02:45 PM
Ok, now I got it, thanks!