XRGB-3 with Japanese NeoGeo - some sync problem? how to solve?

Hello everyone!

I am a NeoGeo collector for more than 15 years and I am now trying to connect my AES system to an HDTV.

So lately I bought one XRGB-3 converter from Micomsoft which I just received a few days back. I am having some sync problems and hopefully someone could tell me how to fix these?

My setup:
-XRGB-3 with english firmware update
-NeoGeo AES with euro RGB cable and adaptor (jap->euro RGB) for GAME IN
-a SONY PC screen connected to the XRGB via VGA for B1 mode
-NeoGeo serial number is above 330.000

the image looks great, I love these scanlines and the only issue I have is that on the top of the screen the image is wavy. Also when I turn AFC mode on the XRGB-3 to 5 the screen is perfect, the edges and all are OK, but it blinks a lot and can hardly see anything. Only on AFC set to 0 the image is stable and sharp (no blinking), but then I see that the upper part of the screen the image is waving like in the photo I show below. When AFC is set up to 3 or 5 the image is OK.
So maybe it is something that has to do with AFC settings only?
Has anyone this similar setup, and have you experienced the same or is it only due to my monitor? I checked on PC monitors so far and all them had the same problem.

Does anyone know how can I correct this? Is this normal or simply my PC monitor is unable to handle the image properly? I plan to buy a LCD TV shortly hopefully I will not have the same problem there .

Also, are there any recommended settings for this setup?

I have attached a screenshot to see the problem:

http://www.flickr.com/photos/flamenquin2001/4910327010/#

I have been told to modify the Euro RGB cable to use a LM1881 video sync chip inside, but I do not have any soldering skills and do not know how to do this. Is there any easier way (ie rewire the RGB cable? use an original Japanese RGB cable instead?) If so what are the steps I should follow?

Hopefully someone can help me on this Thanks!

The XRGBs have sync problems when composite video is used instead of composite sync. See this thread, for instance:

http://www.neo-geo.com/forums/showthread.php?t=211322

Your Neo Geo doesn't output composite sync at all because it's revision 3-6:

http://gamesx.com/wiki/doku.php?id=av:neogeoav

Therefore, rewiring cables won't solve anything. You can either use a LM1881 to get sync from composite or modify your Neo Geo internally so it can output sync like the earlier revisions (the method I prefer). Both methods require soldering.

MKL, thanks so much for your tips and advise. I think I can give it a try on modding the AES, the modification in the link you posted seems simple, but I do not have much experience on it.
If you had some time and experience and could tell me exactly what should I remove/link, I will try it on in a few days and would really appreciate it. Also a process on how to unfix would help - just in case
I can post some pictures of the AES board if this would help to clarify as well.
I bought the XRGB-3 with the only purpose of plugging my AES to a better tv, so I will try as much as poosible to make this work.

I have taken some photos of the AES board that can be accessed here:

http://www.flickr.com/photos/flamenquin2001/sets/72157624779345790/

Revision is 3-6

I have reviewed the previous post mentioned but seems the previous board and mine are different revisions, is there any simple way I could mod my AES to get the desired sync?

I am also using this adapter to connect the RGB to the XRGB-3:

http://cgi.ebay.es/Micomsoft-XRGB-R...g-adaptor-/160463188589?pt=LH_DefaultDomain_3

Which option would be better? To mod the AES or add the LM1881 to this adaptor, if is this possible? If the mod is easy to do I think I will go for it straight away

The internal mod is easier as you don't need to buy any component and there's only one wire to solder. Also you want to mod the system anyway as the RGB output of your 3-6 revision is affected by a well-known issue, a vertical stripe pattern all over the picture. This is also very easy to sort out and doesn't require soldering. You need to unscrew the board and take a pic of the underside of this area:

http://farm5.static.flickr.com/4095/4915125713_bf4c52b499_o.jpg

I think the vertical stripe pattern is fixed already, since I sent my AES to fix the image quality to the same guy who installed the UNIBIOS.

Do I still need to take picture of the bottom part if I want to do only the sync mod?

yes

the board is solidly attached to the bottom cover, i removed all screws there but still attached. any hints how to lower the pressure, what about the controller plugs and memory card slot and so on need these to be removed as well?

The screws on the cart slot and memory card.

done, quick and easy

underside attached on the link below:

http://www.flickr.com/photos/flamenquin2001/4916124582/

First of all keep in mind that even if the XRGB will work fine with the csync, your monitor might not. If it were a euro HDTV I would suggest to hook up the Neo directly to its scart RGB input and see if it has sync problems. But of course you can't do that with a PC monitor.

Anyway, onto the mod.

Since you don't know whether pin 20 of your scart plug (on the cable) is wired to pin 3 or 7 of the A/V port, the safer method is to make both 3 and 7 csync. As a result, composite video will be lost on the A/V port. I don't think you want to use it anyway, do you?

1) Cut the trace highlighted. You can either scrape it somewhere (see how this was done to the RGB traces nearby to fix the RGB issue) or lift it (with a sharp blade, a cutter etc.) and pull it off in its entirety as if it were a hair (this is what I would do):

http://a.imageshack.us/img717/5994/16912726.jpg

2) Solder a wire as shown (tin both ends of the wire beforehand and add some fresh solder to the points on the board):

http://a.imageshack.us/img816/5060/71055244.jpg

That's it.

okay, I will try that later on today and post the results
With this mod, I will still be able to use the Neo plugged directly to to the TV using the 21 pin Euro RGB cable right? I mean in this way there will be no differences, this mod will just help to get rid of the sync problem I faced with the XRGB.
If on a newer tv this problem would not exist, the NeoGeo will not be affected and can still be used with the 21 pin Euro RGB cable directly. Correct?

Sorry I am a newbie I just want to make sure before going doctor with the Neo

PS. The NeoGeo hooked directly to a TV using the normal 21 pin RGB cable works fine all the time. It is just I connected the Neo with an XRGB and then via VGA to a PC monitor then I face the problem.
I had no time to test yet the XRGB via VGA to an HDTV, but will do soon though

Composite isn't needed at all in a RGBS connection.

Does it still have the same problem in B0 mode?

no problem on B0, it works perfectly

todosnk said:

no problem on B0, it works perfectly

Click to expand...

Ok, I did the modification and now I can switch between modes with no problems. The image quality seems to have increased as well and I am happy with the results

The only thing still left is that the image comes and goes sometimes, for about 1 second, then the screen is black until the image comes back again. I have tried with 2 different PC monitors (one of them is a monitor as well as TV), but I am still having the same results (all this on B1 mode. On B0 everything works fine). This flickering does not seem to have a pattern, it can happen once or twice every 10 seconds.

Maybe this has to do with the XRGB-3 settings or the monitor refresh? I am not sure what else I could tune on the XRGB settings. I have tried the recommended settings on wiki but even on low resolutions I still have the problem.
If I plug the Neo directly to the TV, everything works ok. Any ideas?

That sounds just like the issue I had on mine, with Pulstar for instance. I installed an LM1881 and that helped me with losing the signal when the screen went white.

http://shmups.system11.org/viewtopic.php?f=6&t=6987&start=510

I turn it off completely in systems that give no trouble though.

It seems that you couldn't fix the problem you previously had by changing AFC only, a shame.. that worked for my Neos either MVS or AES.

Thanks for the tips, I think I will go for the LM1881 and install it as a last attempt. A few questions to clarify:

1Are there any recommended model brand or installation recomendations (pictures on where to solder it?

2. Would it be better to solder it in the Neo itself, on the original 21 pin RGB cable or maybe in the RGB adapter I am using for the Euro scart to the GAME IN socket (since I have to use this adaptor all the time anyway)?

3. Will the LM1881 get rid of all the black screens or will the games still have a bit of flickering?

If anyone has installed it in a Neo board which is alike the model I have I would appreciate these pics to see how it goes .

Thanks a lot!

I would use the adapter you have. In my case I installed it inside my XRGB-3 as seen in teh pictures of the forum I linked to, with a switch to turn it off completely. This is, for soem uses like CPS-2 teh LM1881 made things worse since it was not needed at all .. hence I installed the switch.

It only helped me with flases to whit in Neo Geo games and on Sonic CD, during similar situations.

Here is a video I made:

http://www.youtube.com/watch?v=1OxmrN6BH0k

As you can see you don't want it to be in there permanently.

thanks Artemio, I suppose this is the way I should go then (and the only one).

Based on that I have done a previous modification in the NeoGeo following MKL instructions in the earlier post, which has helped to increase the quality, and also noting I do not have soldering skills nor understanding of the pins, could someone explain me which are the links I should solder from the LM1881 to the adapter to have this done? a graphical example would really help From my understanding I do not have composite anymore

this is the one I plan to buy:

http://cgi.ebay.es/LM1881-LM1881N-Video-Sync-Separator-PAL-DIP8-/310233726449?pt=Bauteile

ok, I just got 2 small LM1881 circuits and I am now ready to modify the scart cable.

I have this cable to connect my NeoGeo to the XRGB-3:

http://junkerhq.net/xrgb/index.php/XRGB-3#Important_:_about_GAME_IN_input_.28RGB-21.29

Based on that I modified the Neo from a previous post and seems I lost the composite, could anyone indicate me which pins should I solder to have the LM1881 installed on the scart adaptor?
As soon as I have the links I can start with it and report back if the issue is fixed

Thank you!

http://gamesx.com/wiki/doku.php?id=av:lm1881&s

As you can see on the diagram you only need to connect pins:

1 - Your output for sync
2 - Synch input, add the 0.1 uF cap
4 - GND
8 - VCC (5-12V)
6 - as indicated in diagram, 0.1 uF in parallel with 680 ohm resistor to ground.


That's all you'll need.