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neohunter
01-04-2001, 11:41 PM
Hey Guys, I hope someone can help me out. I have a 4 slot neo geo cabinet, and the monitor seems to bounce a little whenever the game has a quick flash or fast animation. Especially when flashing insert coins. The screen bounces up and down a little in unison with the animation. I am not sure if I have a damaged monitor or just a loose conection from the board to the monitor. If anyone has a suggestion keep in mind that I am new to the MVS system and do not know too much about it's inner workings. So walk me through anything technical if you don't mind.

neohunter
01-05-2001, 12:32 AM
Just to update, I have opened my cabinet and noticed that green wires seem to be ground, as they all go to a srew or something metal on the cabinet. There are two green cables that have round metal connectors in my cabinet that aren't connected to anything. Should these also be grounded? Or is there a reason they aren't connected? Anyone with any knowledge about the MVS system please respond. Thanks.

buttonsmash
02-28-2014, 10:26 AM
Just to update, I have opened my cabinet and noticed that green wires seem to be ground, as they all go to a srew or something metal on the cabinet. There are two green cables that have round metal connectors in my cabinet that aren't connected to anything. Should these also be grounded? Or is there a reason they aren't connected? Anyone with any knowledge about the MVS system please respond. Thanks.

Just wondering if you found any resolution to this issue, or if anyone else has some insight. I am experiencing the same issue, where a bright flash on the screen will cause the image to "bounce".

ChuChu Flamingo
02-28-2014, 10:53 AM
It is blooming. It can be caused from too high of contrast and rgb gains (which are affected by your cutoffs).

On the other hand, it can be caused by caps not being able to regulate high voltage effectively. The usual culprit is the flyback HV cap from what i've read. I have this problem a little bit on my Egret II. I reckon it just needs a capacitor replacement since it is nearing 15+ years old now.

Ninja1660811
03-05-2014, 11:04 PM
I have a slight screen problem with my cab as well but not the jumping flicker. I have what seems to be color bleed almost like stereoscopic but not to the point where you can't play. It seems the red is off a bit from the position its supposed to be in. At first i thought it might be the adjustment knobs on the monitor so I proceeded to mess with them a bit and it did move the red a bit closer to where it should be but not fully in place yet. Could this be a cap problem also (my second thought), or could it be something more expensive like flyback or worse? any help on this would be awesome and please don't tell me to replace with led/lcd monitor, Im kind of a purist when it comes to my cabs and consoles (no mods). I loike to play the way they were meant to be played :-)

Thanks for any info in advance

SNKorSWM
03-06-2014, 03:07 AM
If tuning doesn't work, you might need some convergence strips.

Ninja1660811
03-06-2014, 12:18 PM
Im a pretty good geek when it comes to this sort of thing but i have never worked on TV's/monitors. (tube style) but PCB's and the like i have no troubles with. In terms of replacing on a 1 - 10 scale how hard and expensive would this fix be?

Ninja1660811
03-07-2014, 03:55 PM
Bump

Anyone know anything about this?

ChuChu Flamingo
03-07-2014, 05:52 PM
I would head over to http://www.arcade-museum.com/ and register on their forums. They have a tech thread for monitors and are more familiar with American monitors. It would be best to show them pictures of a dot cross hatch pattern to see how aligned (or mis-aligned) your RGB guns are.

Is the red like this all across the screen? Or only on the corners? If it is all across the screen, convergence strips probably wont help. You will need to adjust the red ring manually for that.

Here is the pattern im talking about. Neo geo has built in cross hatch in the bios you can use.

12076

If the guns are misaligned, you will see that the white lines going vertical will be split into whatever color is off or not white at all.

Ninja1660811
03-10-2014, 12:49 AM
Yes I ran that and thought about adjusting the rings(years ago) but as I said before I haven't really tinkered with tube monitors much, so I came here and started poking around the forums and stumbled on a few posts about how the damn thing can fry you :-( So in a way you can say that reading them before messing with shit is a good idea. I ran the cross hatch back then and the red lines were just out of "sync" with the whole grid, so I did some research and heard about the rings. After poking around on the net and finding what I believed to be the solution go and try to fix it. Well, I fire it up, run the cross hatch, pull the panel off and look inside, only to see this pretty amber glow. Not thinking to much about it but knowing that something that glows is hot and probably chock full of electricity in this setting. Gently moving closer to the rings I notice they have some glue on them, so I think ok they must be glued for a reason. That's probably it though, I think the monitors good just needs adjusting because its been that way for years and never got any worse and messing with the pots on board only made the image worse.

Thanks for the tip on where to look.

SSS
03-10-2014, 04:20 AM
I'm assuming this is a Wells Gardner k70000000 whatever series? Unfortunately a good majority of these are beyond their service life. Last ones I messed with changing cap kits, flybacks didn't make a difference. If you get it hooked up to a rejuvenator you can see the condition of the guns. Chances are they are out, and a rejuve may not take. Especially with blue. these monitors are just toasted. Start looking at an LCD alternative. or even easier MAME

the glow is the heater. better yet stop poking around in there with power on make sure you discharge the monitor before service

Ninja1660811
03-10-2014, 10:49 AM
Yeah tell me about it, the blue seems fine its the red that out of whack and yes it is the WG k7 series. Where would I take it to get it hooked up? Tv repair shop? I think I have seen a few cap kits around will try that first.

daskrabs
03-10-2014, 03:28 PM
Regarding your jumping issue, dial back your brightness and contrast, including the sub-bright on the flyback. If that has no effect, I'd sell it as broken and buy a refurb chassis of the same model. If yours is a Wells K7000, these are plentiful and not expensive. If dialing back even partially alleviates the jump, you'll have to play with the brightness, contrast, and maybe the color drive and cutoff to get a decent stable image. This is symptomatic of your tube's color guns (R,G,B) being worn out, which is not fixable, unless you replace the tube.