What's new
By:
Filters

MVS "big red" cabinet, demagnetizing control panel?

Kujako

Kujako

Grand Master
Joined
Jun 3, 2020
Messages
1,315
Reaction score
778
Location
USA, California
I've noticed a small area in one corner of my monitor, that has some minor "rainbowing". My plan was to use a degaussing coil on it, however as I was swapping some games I noticed that it is tied to the control panel and not the screen frame. In fact, closing the control panel causes some interference with some game carts as well... the effect is noticeable on the screen as closing it while powered on has a direct effect on the rainbowing. However, I can not find any part that is actually magnetized (tested using a compass). Anyone ever encounter this, and if so any tips on diagnostics and fixing it?
 
Is the cab grounded?

WHats your PSU voltage running at?

I would check your DC 12,5. It sounds like a grounding supercharge issue.
 
hoagtech said:
Is the cab grounded?

WHats your PSU voltage running at?

I would check your DC 12,5. It sounds like a grounding supercharge issue.
Click to expand...
I'm in the process of reconditioning the power support, not been able to check the voltage yet. Cab should be grounded, but I'll recheck the ground wiring. Any link or details on a "grounding supercharge" issue? That's a new one to me.
 
You just need to degauss the screen when the control panel is closed. The control panel not being magnetized doesn't mean it's not magnetic, all iron is magnetic. A large part made out of iron will have an affect on the magnetic field generated by the yoke.

I don't think grounding plays any part in it.
 
I have a Killer Instinct 2 cab that has this same issue. Control panel clearly messes with the monitor. Degaussing does not work and I'm still looking for solutions also.
 
And you've tried a proper, external coil?

The PTC on the monitor chassis that drives the coil around the tube can go bad and not give enough voltage to the coil to demagnetize the screen fully.
 
I think I have a gaussmeter around here someplace. It's an old cheap one, but may help me narrow down the source of the problem.
 
Did you try to star ground your entire cabinet ? You need to ground your control panel too and check if you don’t have a bad connection from the control wires to the metal of the panel
 
YaYaLanD said:
Did you try to star ground your entire cabinet ? You need to ground your control panel too and check if you don’t have a bad connection from the control wires to the metal of the panel
Click to expand...
Yeah, everything is grounded. But, I have not confirmed that it is a good solid connection. I'll be doing that shortly by checking the resistance from the various components (MVS-2F, console, monitor frame, JAMMA pins, power supply) and the ground lead.

Edit: @YaYaLanD correction, the panel itself is not grounded. Everything else is (confirmed to be a clean connection to the mains ground). Grounding the panel seems like a shocking hazard(?).
 
Last edited:
No, grounding your panel will prevent you from being shocked in case of a leakage...
I suggest you to ground your panel, degauss your screen and see if the panel stops interacting with the screen.
 
I know a buddy that solved a similar issue for another cab using a Faraday cloth. The thing that you put your credit cards, cell phone, and car keys inside of so you don't get hacked.
 
YaYaLanD said:
No, grounding your panel will prevent you from being shocked in case of a leakage...
I suggest you to ground your panel, degauss your screen and see if the panel stops interacting with the screen.
Click to expand...
Turns out I'm just an idiot. The panel IS grounded. I was just testing it on a painted part.

Using the gaussmeter, I do detect a higher reading in the corner of the panel under the effected corner of the monitor. I have no recollection how to translate the readings into milateslas, and the instructions are in german. But the reading is much lower in the other areas. Note that I only get a reading when the cabinet is powered, so it's not magnetized but an electro magnetic field...
 
Last edited:
Just to be sure, is the coin mech located under the control panel, right on the same side as the magnetic field ?

try removing the coin mech, the coil inside it can be your magnetic source
 
YaYaLanD said:
Just to be sure, is the coin mech located under the control panel, right on the same side as the magnetic field ?

try removing the coin mech, the coil inside it can be your magnetic source
Click to expand...
Coin mechanism is about a foot under the center of the console, not really inline with where the apparent problem is. Or are you referring to the coin counter LED?
 
It could be one or the other, maybe both...
Try removing, one then, the other, then both and see if it helps !
 
So... partial mystery solved. The main issue I'm having is that the wiring bundle for the panel is hitting the top of the game carts. I'll need to remove all of the zip ties and try to reposition things.
 
I restored completely a cabinet and i’ve put an MV1 inside. So i also grounded the metal frame to the star ground.
 
Kujako said:
So... partial mystery solved. The main issue I'm having is that the wiring bundle for the panel is hitting the top of the game carts.
Click to expand...
I don't get it. What's causing the magnetism? The wiring bundle?
 
nem said:
Kujako said:
So... partial mystery solved. The main issue I'm having is that the wiring bundle for the panel is hitting the top of the game carts.
Click to expand...
I don't get it. What's causing the magnetism? The wiring bundle?
Click to expand...
I think it's the monitor frame. I'll go about a standard degaussing this weekend. I think the panel was a red herring. When I close it, it moves through the magnetic field of the monitor frame causing a wobble in the picture. Then the wiring presses down on the carts, which was causing some game glitches. Using my gaussmeter I've confirmed that the field it detects is around the monitor not the panel.
 
You must log in or register to reply here.
Back
Top