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opm881
6th July 2008, 12:08 PM
OK! So thanks to serviceit, i finally have access to a transformer that has the proper specs to run the monitor. Ok, so here is whats happening. The screen is a blue when i start it up, even with the degause coil plugged into the monitor. Adjusting the pots doesnt seem to change the colour but one problem at a time. The main problem is that when I start up the monitor with a game board attached that has power going to it(used that home made supergun tut to hook it up to pc power) the thing flips the house saftey. Now, on the chassis the 2A fuse blows when this happens.

So, what are peoples ideas on how to resolve this issue. I might just have to get an arcade power supply but i would like to avoid that if possible. Mainly because if i do that i would need to get a new jamma harness aswell with wiring because the wiring on this one is all soldered to the board and doesnt look very good at all.

David_AVD
6th July 2008, 02:40 PM
To be honest I think you're in over your head and risking the hardware and yourself. It sounds like there is a fairly serious problem if fuses are blowing. When you said safety switch I think we were all thinking earth leakage, but by the sound of it it's really a circuit breaker tripping and that's not good.

Please don't think I'm just trying to put you off so someone can make money from you. You're in a potentially dangerous situation now and we'd hate to see you fry! :059:

opm881
6th July 2008, 02:48 PM
So in other words probably just best to flog it off as is

serviceit
6th July 2008, 03:04 PM
Are you able to take some pic's of this set up?

David_AVD
6th July 2008, 03:07 PM
Not necessarily. I do think it needs someone more experienced to look over it. There's obviously something not right with your setup and by the sounds of it you've reached your (current) knowledge limit with it. In due course you'll be able to solve problems like this but it takes time and more experience. It's a catch 22 situation in some ways! :(

opm881
6th July 2008, 03:16 PM
yep i can put some pics up. Ill pick up some batterys soon for teh digital camera. I dont actually need it david, just wanting to get rid of it and didnt see the point in someone getting a broken monitor. But yea, catch 22 deffinatly :(

shooter
6th July 2008, 03:17 PM
yeah. pay some to come and fix it/have a look at it. I did this with my pinball machine and now im fixing the problems as they come up (all good now). Its just a learning curve. having ap rofessional come in is all part of the learning curve.

narf_
6th July 2008, 03:20 PM
id agree

get the chassis looked at try joey. theres no point getting fried to save a few bucks

or just write it off. better to be safe than sorry

spacies
6th July 2008, 03:24 PM
http://www.thebizofknowledge.com/uploads/electrocution.jpg

serviceit
6th July 2008, 03:47 PM
These are the common Jamma connections you can check to make sure that they have been soldered correctly onto the board. Especially the voltages.


SOLDER SIDE PIN PIN PARTS SIDE
GND A 1 GND
GND B 2 GND
+ 5V C 3 + 5V
+ 5V D 4 + 5V
- 5V E 5 - 5V
+12V F 6 +12V
KEY H 7 KEY
COIN COUNTER 2 J 8 COIN COUNTER 1
K 9
SPEAKER (-) L 10 SPEAKER (+)
AUDIO (GND) M 11 AUDIO (+)
VIDEO GREEN N 12 VIDEO RED
VIDEO SYNC P 13 VIDEO BLUE
SERVICE SWITCH R 14 VIDEO GND
S 15 TEST SWITCH
COIN SWITCH 2 T 16 COIN SWITCH 1
START SWITCH 2 U 17 START SWITCH 1
2P UP V 18 1P UP
2P DOWN W 19 1P DOWN
2P LEFT X 20 1P LEFT
2P RIGHT Y 21 1P RIGHT
2P PUSH 1 Z 22 1P PUSH 1
2P PUSH 2 a 23 1P PUSH 2
2P PUSH 3 b 24 1P PUSH 3
c 25
d 26
GND e 27 GND
GND f 28 GND

opm881
6th July 2008, 03:51 PM
yea, that info was on the homemade super gun site. Good to know it was correct.

GameDude
6th July 2008, 05:58 PM
I would say that you probably have the GND from your PCB power supply and the GND from the monitor RGB tied together with the chassis GND, if either are live then that would explain blowing fuses and tripping breakers.
RGB GND is almost always hard wired to common PSU GND by the PCB. But on your chassis if somehow the RGB GND is attached to the live parts of the chassis or there is a leak on the chassis to GND then that would explain it all.
I am betting when the PCB is attached you give the live chassis a direct path to earth or offer little resistance thus blowing your breakers.
you may have stray wires, or unknowingly earthed or have stray solder touching what should not be touched.... I think its the wiring but NOT the JAMMA harness itself..
Oh and a quick test with a multimeter on continuity will almost always prevent high voltage wiring mistakes... But I cant tell you how to do it....

opm881
6th July 2008, 07:47 PM
ok ok, i will try and interperet what you said xD Not your fault, i just dont work well with this stuff without examples/pictures :P

Ok, so the ground for the video output on the harness is connected to the ground that the pcb uses and so is using the same ground as the board itself. Now, what ground on the chassis i have no idea what your talking about. The chassis uses an american plug

serviceit
7th July 2008, 07:29 PM
Just to help in the process of elimantion, i can lend you a proper P.S.U if you want, but you will have to come over and pick it up. Do you own a meter?

opm881
7th July 2008, 08:11 PM
No I dont own a meter, but thanks for the offer any way service. I just want to be rid of it. I have a couple of assignments that I need to do before I go away next week, and then when i get back I have more assignments to do so yea