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Main => Monitor/Video Forum => Topic started by: mann0mann on January 20, 2014, 03:13:42 am

Title: WG 7000 Neo Geo MVS-4-25 (ver 1) Cab - Black Level Bouncing
Post by: mann0mann on January 20, 2014, 03:13:42 am
I just recently picked up my first arcade cabinet, a Neo Geo MVS-4-25 version 1 cabinet.  The monitor appears to be in good shape, there is no burn-in and I've been able to use the TEST menu and screens to adjust the colors, position, etc pretty well.  My problem seems to be with the contrast setting though.

I've adjusted the rear neck board pots first.  There's not much you can I could do with the Focus and Screen adjustments, the amount I adjustment was minute before the picture would not be agreeable.  My setup uses a 6 pot remote board for the remainder of adjustments other than color.  It's a P802 remote board.

I've got the contrast all the way down, if I turn it up I begin to see ghosting on the images.   And with my board the BLACK LEVEL is turned all the way up. 

The cabinet is in the garage.  I am in Northern California, but it's still relatively cold.  When I turn on the machine, at start the monitor is almost too dark.  The darker details of Metal Slug and Aero Fighters for example cannot be seen.  However after about 30 minutes of being on, the BLACK LEVEL will begin to bounce and flicker occasionally and then for the most part settling at a LEVEL that is almost perfect, maybe just a little too light.  I obviously could adjust it down on the remote board then, but then on the next startup it would be completely unplayable.

I'd also say that even though it basically "stabilizes" it does seem to occasionally bounce a little even after being on for hours.

I'm kinda at a loss at what is causing it.  The wiring harness to the remote board doesn't seem to have any breaks or shorts in it.

Could it be that my pots are bad on the remote board and they need to be replaced?

or Do monitors just need this long to "warm" up and I need to live with this?

Any ideas?
Title: Re: WG 7000 Neo Geo MVS-4-25 (ver 1) Cab - Black Level Bouncing
Post by: buffett on January 22, 2014, 01:38:48 am
has the chassis had a cap kit and new flyback installed.

if not now is the time to do it.

the Neo Geo is hard on a K7000 because of all the contract changes from black to wite constantly.

this is a natural thing but if your monitor has never had a good rebuild it will be worse and get worse.

if you need your monitor fixed you are welcome to send it in.
email me from my website.

thearcadebuffett.com

Peace
Buffett
Title: Re: WG 7000 Neo Geo MVS-4-25 (ver 1) Cab - Black Level Bouncing
Post by: mann0mann on January 23, 2014, 08:06:41 pm
I did do some more work on calbrating it and it's definitely an issue coming from the Flyback.  The Flyback Coarse screen adjustment is not right,  if you even barely adjust it, it's the cause of the issue. 

Curious, not to talk business here on the forum.  But I see you sell working chassis replacements for the same price as a repair.  How do you handle a trade-in?
Title: Re: WG 7000 Neo Geo MVS-4-25 (ver 1) Cab - Black Level Bouncing
Post by: buffett on January 24, 2014, 01:46:32 am
if you cannot adjust the screen brightness the you need a rebuild ASAP because the fly is getting ready to fail.

i do not talk money or prices in the open that is not how i do things.

for the trade in you send me the chassis and i will let you know what i give for it.
each chassis can be a different value depending on condition.
i then take the value off the repair or refurbished chassis.

Peace
Buffett