MVS 25" Monitor issue, can you help?

Capt. Lurker

There's a post count?What the fuck isThat All abou
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Okay, got my cab upstairs and what a chore that was.

Here is the issue that after looking at the cab more closely, I noticed something odd and I don't know how to fix it or even what it is.

At the top of the screen, there is about a 2-3 inch space where the graphis are real sharp. Anything below that appears to have tiny black lines from left to right, again all the way down to the bottom. It appears as if you can see each individual row of graphis.
Now let me state, the entire screen looks pretty darn good, but that top 2-3 worth looks as if the rest of the screen was like that, it would be absolute bliss/perfect because it so crisp.

What's going on here? Is my screen on the way out the door? I messed around with the 6 screen adjusments but it still has the same issue. Not sure if there are other ways to fix this? When playing Shock Troopers, while scrolling up, in that 2-3 space the graphics get waving as you progress in the game. however when things go horizontal, that issue doesn't exist even with Slug 5 or Blazing star. It only happens when the screen is progressing in vertical motion.


Side issue now that I think of it.
With the 4 mini marqs at the top, number 2 and 4 light up fine when the games are selected. However 1 and 3 appear to be attempting to light up (you can barely see it) and they make this super annoying high pitched ring noise. What gives with this? I unpluged it because it was only happening when 1 and 3 would light up. Very strange.
Sorry for all the questions, wish I knew more about this stuff.

Fixed my 2nd player controller issue also, that was easier than I thought it would be. I just took the c-clip off and placed another washer and clipped it all back. Works like a champ now. thanks for the tips from my other post.

I promise to get pics up too. I took them but it got late and I didn't get time to post them. Thanks in advance for any help.
 

Lashujin

Ghost of Captain Kidd
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Dec 2, 2002
Posts
1,654
On the flyback tx (follow the wire from the suction cup to a little box) of your monitor there is a focus and master brightness dial (most of the time these are unlabled), play around with these two and it will likely fix the issue.

BE CAREFUL, as there are lethal amounts of electricity contained in the caps when the monitor is off.
 

Capt. Lurker

There's a post count?What the fuck isThat All abou
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Lashujin said:
On the flyback tx (follow the wire from the suction cup to a little box) of your monitor there is a focus and master brightness dial (most of the time these are unlabled), play around with these two and it will likely fix the issue.

BE CAREFUL, as there are lethal amounts of electricity contained in the caps when the monitor is off.


These dials you speak of are completely different from the 6 dials that are in front of the 4 slot board?

I have played with the 6 dials that are on a small chip board. That chip board lives right in front of my 4 slot board.

The six dials basically control side to side, up and down adjustments and the others control what appears to be brightness and contrast. Also there is one dial that (when you turn it either way) makes the screen start srcrolling very rapidly up or down. Waving is prolly better word to use for that. Then the other dial expand left and right and expand up and down.

So if there is other dials, then I am not sure where else to look? Plus how does one actually get to the back of the monitor without cooking themselves into a tasty BBQ human?
 

Lashujin

Ghost of Captain Kidd
Joined
Dec 2, 2002
Posts
1,654
GT40PWR said:
These dials you speak of are completely different from the 6 dials that are in front of the 4 slot board?

I have played with the 6 dials that are on a small chip board. That chip board lives right in front of my 4 slot board.

The six dials basically control side to side, up and down adjustments and the others control what appears to be brightness and contrast. Also there is one dial that (when you turn it either way) makes the screen start srcrolling very rapidly up or down. Waving is prolly better word to use for that. Then the other dial expand left and right and expand up and down.

So if there is other dials, then I am not sure where else to look? Plus how does one actually get to the back of the monitor without cooking themselves into a tasty BBQ human?

Yes, these are different dials then the ones on the front. I don't know how you access the monitor on you cab, mine has a panel on the rear that opens up.

To find the dials follow the wire that comes out of the suction cup on the back of the monitor and the little plastic housing it goes into is the flyback transformer, the dials are on the side of this.
 

ttooddddyy

PNG FTW,
Joined
Nov 29, 2001
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8,335
We are talking about the screen voltage adjustment on the flyback transformer. Its the lower of the two pots (the top one being the focus pot)

Turning it anti clock slightly will reduce the screen voltage and possibly fix the problem.
 
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