Hantarex MTC 9110 Horizontal lines, Red pic. and black ghostlines (pic included)

[psyking]

Hey!

I just bought and rebuilt a Rene Pierre arcade and I'm having some disturbing problems with the picture.

The arcade has a Hantarex MTC 9110 monitor and it uses a Jamma connector. (it has no game pcb now, but the power supply is for both the monitor and game pcb)

Before I bought the arcade I played it's original games (3 NeoGeo games) and the picture on these was superb. The games were removed when I purchased it.

Now that I've installed a computer with a arcadevga card I experience some problems with the picture. I have tried adjusting the picture to resolve them using the controls inside the cabinet: horizontal & vertical sync, vertical & horizontal size & position, brightness (screen) and focus.

1. There are some horizontal lines at the top of the screen (static, not moving). These are displayed from bootup (dos) to windows and in mame games. The only difference is that in dos/windows mode they show across the entire top screen and in mame games on a smaller portion of the screen. At one point during bootup in dosmode the lines show up across the middle of the screen too, but just for a second or two, and then they disappear.

2. There is a slight red'dish color to the black parts of the screen, not visible at texts really, but if you look at the bombjack highscore picture and arkanoid one below you see what I mean.

3. There are black ghostlines on the windows screen, look at the right to the window that is open.

4. Last but not least there are the "rolling" static (lines) on the screen in mame games. These are also visible on windows, and even worse, but this is due to interlace I guess.

I've read about this last problem and that it might have to do with grounding of the monitor. From what I can see in my cabinet the monitor has a metalwire around it that has a groundwire soldered to it that goes to the card which has the light bulb attached to it.

Another ground is the one that goes to the monitor pcb and then to the jamma connector. Since the jamma isn't connected to any game pcb I wonder if this works as a groundpoint? Or should I desolder this and solder to some other place in the cabinet?

I haven't yet touched the rgb cutoff / gain since the picture was good with the original pcb games.. Is this something to mess with? Also I find it abit scary to poke around in those parts due to the risk of zapped.

Appreciate any input on these problems.

[psyking]

Some more pictures.. Btw the picture are somewhat out of focus, so that isn't due to the monitor display

[MonitorGuru]

These lines are "vertical foldover" caused by the fact that you are overscanning the screen so significantly.

Think of it like folding a newspaper over on the edge... the writing will bounce back and be printed backwards On a monitor this will also begin to stretch where it bounces back giving the separating in the lines.

To fix this you need to significantly reduce your vertical size. Either by adjusting the vertical size pot or moving jumpers on the monitor chassis, OR adjusting Mame video output. You didn't say what you are using... are you using an ARCADEVGA card or are you using AdvanceMame?

[psyking]

Thanks for all the help mate. I'll get right on it and see if I can fix these first three problems i'm having.

I did say that I had ArcadeVGA but I guess you must have missed it:

> Now that I've installed a computer with a arcadevga card.

About the "rolling" static (lines) in mame games, do you mean that even these can be affected by a interlaced resolution in windows? Since mame changes the resolution for each game I didn't think it would matter what resolution I used in windows..

[dabone]

The mame tearing is caused by not having triple buffering enabled.


Enable it and all should be well on that issue.


Later,
dabone

[psyking]

Now i have tried all of the above suggested solutions except the red cut-off which I will do later, my first priority is to solve the phantom lines.

When I reduced the screen size using both the pot inside the arcade and the settings for resolution in mame I got rid of the phantom lines at the top of the screen.

But there are still phantom lines near the bottom of the screen, and these are always running all the way across the screen. These are the same ones that I mention showing up for only a second during boot, when going from dos->windows.

I tried shrinking the display (with the pots) to a very small vertical size just to see if they would go away as the ones in the top did, but they just followed the screen along.

I've tested a bunch of games and I found one game that with specific settings didn't show any of these phantom lines and it was Ghost 'n Goblins. What I did was that I removed the "Stretch Using Hardware" setting in Mame. The reason this seems to work in Ghost 'n Goblins only and no other games that I've tested so far is that GNG's hz is H60 and not V60 as the rest.

Does anyone have any clue to what may be causing this? It seems as if as soon as the Vertical sync is involved it messes up

Btw: Enabling "triple buffering" didn't give me any change in the picture whatsoever.

I also included a picture of the inside of my arcade, showing where I soldered the ground from the RGB wire. I'd like to know if this is a suitable spot to do this?

[psyking]

more pictures...

[MonitorGuru]

Your red drive is up too high and you're seeing the red retrace lines now... different than the foldover lines. Turn down the red drive (and may need to play with the cutoff control) and it should help.

[psyking]

But how come I can get them to disappear when altering the Hardware Stretch option and only on games that has H60 in their resolution?

You are refering to the three thin (1 pixel in height) brighter red lines that are visible on the lower part of the screen right? (look at the first bombjack picture and just below the 1coin/ 1credits text). Just so that you did catch those and don't mean the big/wider ones that are located all over the screen.

Since these three lines looks exactly the same as the ones I used to have on the top of my screen with the same color, 1px height and leaning down abit.

Thanks for all the help so far mate, been really useful. I'm gonna try and adjust the red gain/cut-off's tomorrow. For these I can't use the pots right, I mean they don't fit in there? I need to use a screwdriver for them?

[psyking]

Now I have adjusted the red cut-off and gain pots and even though I lower the red cut-off to its absolute minimum the lines are still showing. If I lower the brightness pot very low too then I get rid of them but instead the entire display is very dark.

There supposedly should be two ways of adjusting the brightness, one is the brightness pot of which I've located and a screen pot which I can not find.. In the manual for the monitor there is a schematic of all the available pre-set adjustments and the one for screen points to a red cable and not a pot, so I'm guessing this isn't adjustable with this particular monitor then?

[MonitorGuru]

screen pot is on the flyback transformer next to the focus pot.

Only other thing i can think of is your video card is putting out wrong colors in certain modes. Connect it to a computer monitor and see what it looks like (the image will roll or shimmer but you should be able to tell if there is a red bias)

The 3 thin diagonal lines are indeed retrace lines, which means your screen control is generally set too high (specifically, it is high and the green and blue drive controls are probably lower than the red, thus you only see the red retrace). OR you could have a small heater-cathode short in the red gun, however that would appear on all images not just on certain ones. Therefore I would think that this red bias problem, if only in certain resolutions, is an issue with Mame/video card, not the monitor, but since I'm not there to mess around with the controls myself, I can't say for sure.

[psyking]

The pot located next to the focus on the flyback transformator is labeled as brightness in the manual, but then it is the correct one that I have been adjusting then.

I finally found a solution to get rid of the lines, I found a "brightness preset" adjustment which i set to it's maximum level and then I lowered the red gain somewhat and the lines are gone and screen is at a reasonable bright level.

Thanks for all the invaluable help MonitorGuru =). Now I'm gonna make sure all the groundings from the monitor is correct and most likely the display will be topnotch.

Btw, is there any good software out there (except NokiaTest) to make monitoradjustments easier and more precise? I tried using the NokiaTest software but I can't say that it helped me much really, especially when it comes to these rgb cut-off and gain stuff.