Hantarex Polo/Jpac screen wobbling issue??

[teartray]

I have mentioned this issue in a previous post amongst other issues but haven't been able to solve this one. The screen has a slight, vertical wobble that's in motion. It is more prominent on the left side of the screen. I am running windows XP with an Arcade VGA.

It is only preseent when using non-interlaced resolutions: 640x288; 384x288; 352x288. Most other resolutions I have tried result in a severely flickering image but minus the wobbling.

The native resolution of the arcade cabinet is 320(321)x240 and if I set it to this, the screen does not wobble but does moderately flicker and again, it is more prominent on the left side.

There is no flicker or wobbling present when I connect the original Jamma PCB.

I suspected it might be that the VGA cable wasn't shielded, so I replaced it with a high quality shielded VGA cable but the problem still persists. I then thought it might be a an issue with the Arcade VGA card so I installed an unmodified graphics card and ran Soft15khz but yet, the problem was still present.

I have spent hours adjusting the h-sync, v-sync pots etc but it still won't disappear. I even bought a new remote PCB but it's still present.

Due to this only being present when the PC is connected, it is obviously something to do with this and not with the actual monitor.

Could this maybe have anything to do with power still being supplied through the Jamma harness? I understand power was supplied to the original Jamma PCB through the Jamma harness, could this problem be due to this power still being connected?

I have researched the problem on here and google and can't find anyone experiencing the same problem.

Does anybody have any ideas? I'd appreciate any help you can offer. My cab will be pretty much perfect if I can resolve this issue.

[teartray]

I have been away at University and so haven't worked on this for some time, I have been playing around with it and I still cannot get rid of the problem.

I am also having a problem with connecting an external monitor to the DVI port as I have mentioned here - http://forum.arcadecontrols.com/index.php?topic=111621.msg1184958#msg1184958

I also can't get games to work at their native resolutions. I have tried using th Arcade Res utility and used both the "closest x y" setting and the the "proportional" setting and the result is the same: some games such as Donkey Kong, the image seems to be cut off at the top and kind of rolled behind itself and other games like Street Fighter II do not fill the screen. See pictures below.

 

The only way I can get all the games to fill the screen correctly is by deleting individual ini files and by using very minimal settings in the mame.ini file (as shown below) instead of the more comprehensive settings, but the graphics are not as defined using these settings as I believe this may be using hardware stretching.

#
# PER-WINDOW VIDEO OPTIONS
#
screen                    auto
aspect                    4:3
resolution                352x288
view                      auto
screen0                   auto
aspect0                   auto
resolution0               auto
view0                     auto
screen1                   auto
aspect1                   auto
resolution1               auto
view1                     auto
screen2                   auto
aspect2                   auto
resolution2               auto
view2                     auto
screen3                   auto
aspect3                   auto
resolution3               auto
view3                     auto

#
# FULL SCREEN OPTIONS
#
triplebuffer              0
switchres                 0
full_screen_brightness    1.0
full_screen_contrast      1.0
full_screen_gamma         1.0

You can also see the weird wave on the left side of the street fighter image and that is actually in motion, rippling up the screen like a Scooby Doo dream sequence!

I simply can't enjoy this machine with these problems and I would be happy if I could just get rid of the wavey picturte effect as this is my main concern.

I would appreciate any help anybody can offer.

[krick]

You really should disconnect the cabinet DC power supply and see if the problem goes away.
I strongly suspect it's somehow related to your issue.


For making games run at their native resolution, check out GroovyMAME.  It's awesome.
It automatically picks the best resolution for most games without the need to create game-specific ini files.

http://forum.arcadecontrols.com/index.php?topic=110905.0


You'll probably need to adjust your monitor's vertical height a bit so that vertical games like Pac-Man don't get cut off at the top and/or bottom, but once you've done that, everything should look pretty damn good.

I enabled "soundsync" after generating a new mame.ini file from GroovyMAME.  This helps prevent tearing by adjusting the emulation speeds of some games when the refresh rates don't match.

[teartray]

You really should disconnect the cabinet DC power supply and see if the problem goes away.
I strongly suspect it's somehow related to your issue.


For making games run at their native resolution, check out GroovyMAME.  It's awesome.
It automatically picks the best resolution for most games without the need to create game-specific ini files.

http://forum.arcadecontrols.com/index.php?topic=110905.

You'll probably need to adjust your monitor's vertical height a bit so that vertical games like Pac-Man don't get cut off at the top and/or bottom, but once you've done that, everything should look pretty damn good.

I enabled "soundsync" after generating a new mame.ini file from GroovyMAME.  This helps prevent tearing by adjusting the emulation speeds of some games when the refresh rates don't match.

Thanks for your reply.

I have adjusted the vertical height and the other pots many times to try and rectify some of the issues but it never works. I shall definitely try GroovyMAME tomorrow 

With regards to disconnecting the DC power, I have read that the waving image may be some kind of power interference whilst googling the problem, but was still not sure how to go about fixing it. I'm afraid I am very clueless when it comes to the electrical wiring of the cabinet so am unsure what I need to disconnect. I assume it would be one of the connections in the photo I have taken, shown below?

[teartray]

This is from the cabinet instruction manual.

[krick]

I can't see any of your pictures.  I don't think you can link them directly from your mail account.  You'll have to attach them to the posts, or stick them up on imageshack and link to them.

Disconnecting the DC power supply in your cabinet should be fairly easy, depending on your specific cabinet.

This page on Bob Robert's site explains JAMMA cabinet A/C wiring pretty well...

http://www.therealbobroberts.net/acwiring.html


Below is a picture with a red X showing the two wires that should be disconnected.  You want to make sure that everything is unplugged when you unhook them so you don't get shocked and then make sure that you cap any resulting loose hot wires with wire-nuts.  We don't want you burning your house down.

[teartray]

I can't see any of your pictures.  I don't think you can link them directly from your mail account.  You'll have to attach them to the posts, or stick them up on imageshack and link to them.

Disconnecting the DC power supply in your cabinet should be fairly easy, depending on your specific cabinet.

This page on Bob Robert's site explains JAMMA cabinet A/C wiring pretty well...

http://www.therealbobroberts.net/acwiring.html


Below is a picture with a red X showing the two wires that should be disconnected.  You want to make sure that everything is unplugged when you unhook them so you don't get shocked and then make sure that you cap any resulting loose hot wires with wire-nuts.  We don't want you burning your house down.

Thanks. I've added all the images to Imageshack and relinked to them, so you should hopefully be able to see them now.

I have located the wires you have shown in the image you provided, I think it is the 2 wires on the far left as shown in the image below, the two purple ones going in to the switching power supply, with the two black ones going out toward the jamma harness.



Do I just need to disconnect the black wires and leave the purple ones connected, and will doing it this way still require me capping the black wires as they won't be live will they? Or do I need to disconnect the black ones and the purple ones?

[krick]

You shouldn't need to disconnect any wiring in the JAMMA harness itself (the "JAMMA Chart" picture).

I think the two purpley wires on the left are the 120V wires feeding your DC power supply.
Check the labels on the DC power supply itself where the wires attach.  I think they say "AC".

You should be able to disconnect those two wires.  That will remove the power from the DC power supply.

Where are the two black wires going?  I suspect they're going either to your monitor, or the marquee lighting.  If that's the case, you'll need to disconnect those wires from the DC power supply and connect them to the hot wires again.

The bottom line is that you want NOTHING connected to the 120V AC screws on the DC power supply. 

I'm not sure about the greenish wire next to the purple ones.  That should be an earth ground, and leaving it connected shouldn't hurt anything.  HOWEVER, that is honestly the worst wiring job I've ever seen, and there appears to be a ground loop between the AC side and the DC side, that might be where the noise was coming from all along.  See if disconnecting the two purple wires does the trick.  If not, we'll go from there.

Here's how the wiring should look (minus the earth grounds).  Just disconnect the AC from the Power Supply.

[teartray]

I have disconnected the two purple wires but the problem is still there.

The black wires were going to the fan that cooled the Jamma board, which I had previously disconnected at the fan anyway.

[teartray]

I've disconnected the green wire also, but the problem still persists. This surely has something to do with Jpac as the problem is not there when the original jamma board is connected?

[krick]

The JPAC is powered by your computer's power supply.  Maybe it's getting noise from there.  Do you have access to a different computer or power supply for testing purposes?

[teartray]

The JPAC is powered by your computer's power supply.  Maybe it's getting noise from there.  Do you have access to a different computer or power supply for testing purposes?

Thanks for the suggestion. Just connected a power supply from another computer but it didn't resolve the issue 

[teartray]

I'm not sure about the greenish wire next to the purple ones.  That should be an earth ground, and leaving it connected shouldn't hurt anything.  HOWEVER, that is honestly the worst wiring job I've ever seen, and there appears to be a ground loop between the AC side and the DC side, that might be where the noise was coming from all along.

Is it possible for this ground loop to cause the interference, even with the purple wires disconnected? Or maybe the caps that are linking some of the terminals are causing it, as I have never seen these caps on wiring diagrams?

[krick]

You can safely disconnect EVERY wire from the DC Power supply.   Just make sure the loose wires are taped off with electrical tape to make sure nothing shorts out.

Do you have a fluorescent marquee light?  Maybe the JPAC is picking that up.

[teartray]

You can safely disconnect EVERY wire from the DC Power supply.   Just make sure the loose wires are taped off with electrical tape to make sure nothing shorts out.

Do you have a fluorescent marquee light?  Maybe the JPAC is picking that up.

I have disconnected every wire from the DC power supply and disconnected the fluorescent light but sadly the problem is still there     

This problem is so frustrating as it is really preventing me from enjoying this cab.

I have had a look around the back of the monitor and noticed some more potentiometers that I haven't noticed before.



There are two on the small vertically orientated board and one, without a knob, on the main board. There are also some more on the neck board which are a bit awkward to get to and also have no knobs.

I am a little apprehensive about messing around back there, do you know what these are and if adjusting any of them would solve my issue?

Thanks.

[krick]

I'm not sure that the problem is in your monitor and I wouldn't go fiddling pots just yet.

Like you said earlier, when you connect a JAMMA board, the problem is not present.

Is your PC close to your monitor in your cabinet?
Are there any AC power wires running near any of the signal wires going into your monitor?
Is your cabinet's AC cord properly grounded?
Is your PC AC cord properly grounded?
Do you have any kind of amplified speakers in your cabinet?

You might want to get a helper to move wires around in the back of your cabinet while you watch the screen to see if anything affects it.

You could also try physically moving your PC as far from the cabinet as possible to see if it makes any difference.

Also, you could try plugging the PC into a different circuit in your house to see if that helps.

I'm really at a loss at this point and you pretty much have to try everything until you isolate what's causing the problem.

Do you have access to any other JAMMA boards that you could use for testing?

[teartray]

The PC components are now mounted inside the cab, but the problem was present back when the PC was still in its original casing and placed as far as possible from the cab.

The only AC wire running near the signal wire is the AC wire for the monitor itself. A power cable was running near the JPAC to the coin-slot bulb, so I disconnected that.

All of the ground wires for the cabinet seem to be routed to the the bottom; because it works with the original JAMMA board, I doubt that would be the issue.

I have tried different PC power cords but still no luck.

I do have amplified speakers but I have disconnected the amplifier.

I tried plugging the PC into a different circuit using an extension cable but it had no effect.

I've tried moving the wires about however, most of the power wires are on the opposite side to the JPAC.

One thing to note is, while doing all of this, I pulled the PS/2 cable from out of the JPAC, thus disconnecting it's power. I was expecting there to be no image on the screen, however, the image was still present but a lot darker and vertically scrolling. It took some time to keep the image still and I turned up the the brightness to compensate for the dark image so I could see the picture and I found that the wavy interference, while still present, was quite reduced. I am wondering if there is some unnecessary voltage travelling down the VGA cable and the JPAC is amplifying it? I noticed my VGA cable has pin 9 missing, though this is the cable that came with the JPAC so I presume this is normal.

[krick]

The JPAC has an amplifier in it, so any noise in the video from your PC will be amplified.

It appears that your PC is generating the noise, or your video card is picking up interference from something and transmitting it.

Some possible causes of RF noise in a PC:

1) insufficient shielding (case)
2) faulty power supply
3) fans or pumps (water cooling)
4) overclocking

[teartray]

The JPAC has an amplifier in it, so any noise in the video from your PC will be amplified.

It appears that your PC is generating the noise, or your video card is picking up interference from something and transmitting it.

Some possible causes of RF noise in a PC:

1) insufficient shielding (case)
2) faulty power supply
3) fans or pumps (water cooling)
4) overclocking

After all of this, I was so convinced that this would be the problem as I had never actually thought of hooking up a completely different PC. However, I have just connected one and the wobble is still on the screen! It must be something to do with the JPAC. I know the problem was still there when the JPAC wasn't powered but maybe because the signal was still travelling through the JPAC, it was somehow still effecting it? It can't be the monitor because of the original JAMMA board working perfectly. I am going to connect the original JAMMA board up again just to confirm again that it works without the screen wobble. Other than that, I don't know what else I can do.
I suppose I can email Andy from Ultimarc to see if he can be of any help.

[krick]

I suppose I can email Andy from Ultimarc to see if he can be of any help.

I'd do that.  It can't hurt.  Andy has been doing this for a long time and has seen a lot of stuff over the years, so maybe he'll have some ideas.

I have one last thought...   try unplugging the fan on your ArcadeVGA to see if the wobble goes away.  Don't run it for a long time without the fan though.  You don't want to damage it.  You might also want to rig up another fan to blow on the card during the test, just to be safe.   As long as you're not putting the card under heavy load for a long time, I think it should be OK.

[teartray]

I have one last thought...   try unplugging the fan on your ArcadeVGA to see if the wobble goes away.  Don't run it for a long time without the fan though.  You don't want to damage it.  You might also want to rig up another fan to blow on the card during the test, just to be safe.   As long as you're not putting the card under heavy load for a long time, I think it should be OK.
[/quote]

I haven't tried that but I have tried using two different graphics cards with Soft15khz.

Here is a video of my problem, the wobbling is most prominent on the lower left side of the screen:



It looks worse with the naked eye. The lines at the top disappear if I adjust the brightness, but will reappear in bright scenes of certain games. I assume this could be fixed permanently with a capkit?

[teartray]

I also found this:



Someone in the main forum said this is a grounding wire that should be attached to the monitor frame. It seems to be connected to somewhere underneath the coin counter at the bottom of the cabinet. Any idea where about it should be connected on the monitor frame? Maybe this could solve the issue?

[RedPainter]

Have you solved your problem?
My problem seems very similar to yours.

If I use my DIY VGA to Arcade Monitor it works very well, but with J-Pac the picture has a strange image, like ig there is some problem with interlacing.
Also Jamma PCB games have perfect image.

[teartray]

Have you solved your problem?
My problem seems very similar to yours.

If I use my DIY VGA to Arcade Monitor it works very well, but with J-Pac the picture has a strange image, like ig there is some problem with interlacing.
Also Jamma PCB games have perfect image.

No, I still haven't been able to solve it. I was thinking of just getting a new monitor but if your DIY connection works, maybe it is a JPac issue. Can you explain how you connected through your DIY method?

[teartray]

It's been some time since I have been playing with my arcade cabinet but I'm now back on it again and still having this issue, among other issues. Does anybody know how I can resolve this or did I get a faulty JPAC/ArcadeVGA? Any help would be hugely appreciated.

[adder]

connect that wire to the monitor frame yea (anywhere on the metal frame, as long as it is then making the ground connection.. do u use a multimeter, if not get one and learn the continuity test eg. youtube video etc)
regarding the wobbling, try moving the jpac away from the isolation transformer if it is close to it

[mgb]

Not sure I'm missing something here but I didn't see any video showing the wobble you're talking about, but on arcade monitors, a bad b+ power filter cap will cause a wobble.
It's the large cap (or two) on the monitors chassis board.