Okay, again, consoles on an arcade monitor...

GaijinPunch · Post by **GaijinPunch** » Sun Mar 09, 2008 5:38 am

I hope elvis reads this. I looked for his post, but can't find it.

Anyways:
I have a beautiful Trisynch arcade monitor. My supergun looks fine on it, as does my DC VGA box. I've not tried the AVGA but I'm sure there are no problems with it either (well, I'm 50/50). The issue comes in when using console games. Still pictures and FMV work fine, but when the screen moves, things go awry. Why is this again, and why do RGB TVs have no problem with either Supergun or console?

I recall having to add a circuit somewhere to something to sort it out, but I'm not so crafty w/ electronics. Modding a stick is the start and finish for me.

Oh, finally -- running things through the XRGB-2 in 15khz mode fixes the problem, so it's still playable with minimal signal loss (I can't tell the difference to be honest)

Any help is appreciated.

cutty_sark · Post by **cutty_sark** » Sun Mar 09, 2008 6:21 am

Which consoles are you trying to plug into it? Some consoles output sync, while others only output composite video. For those you need to use a sync separator circuit to strip a clean sync signal out of the composite video.

Look at the AV Port Pinouts here to see which consoles output composite video only:
http://www.gamesx.com/

Here's how to build the sync separator:
http://www.gamesx.com/misctech/lm1881.htm[/url]

GaijinPunch · Post by **GaijinPunch** » Sun Mar 09, 2008 7:30 am

I tried my Saturn, and a modded Famicom.
So basically in my RGB cable, I need to solder the Compositie Video lead to the LM1881 and viola? Now to let my wife let me use solder in the house. Young kid + paranoid mother = little fun.

D · Post by D » Sun Mar 09, 2008 11:24 am

Have you tried carefully adjusting vert. and hori sync on your tri sync monitor while the consoles are running? That might do the trick. Maybe indeed the signals are too much for the console and you need to 'tone' them down a bit. I have another problem on a rgb tv. When there is a lot of white onscreen, the screen starts rolling.
Try killercabs forum as well, they might know.
What does 'thing go awry' mean exactly? Is it the out of sync rolling I described?

it290 · Post by **it290** » Sun Mar 09, 2008 5:02 pm

If you're getting distortion/rolling when the screen is bright, you probably need to add some resistors to your RGB lines to tone them down, as you say. I had the exact same problem with my SNES's RGB output, and connecting some resistors solved it. You can play with the values to adjust the brightness of the output.

Post by **Dave_K.** » Sun Mar 09, 2008 6:50 pm

cutty_sark nailed it, lm1881 circuit needed to separate the sync.

cutty_sark · Post by **cutty_sark** » Sun Mar 09, 2008 7:53 pm

Hmm. For the Saturn you shouldn't need the sync separator since it outputs a proper sync signal. I have no idea about the modded FC.
It could be what it290 suggested - I had to do the same thing to get the SNES to work on my Wells Gardner. Are you using Japanese 21 pin SCART style RGB cables?

The LM1881 circuit isn't as simple as just soldering the chip to the comp video line. You'll also need a couple capacitors and a resistor in the mix.
This should help with how to read the schematic:
http://www.kpsec.freeuk.com/symbol.htm

indstr · Post by **indstr** » Sun Mar 09, 2008 10:17 pm

GaijinPunch wrote: Now to let my wife let me use solder in the house. Young kid + paranoid mother = little fun.

hey , i have that same problem

fuko · Post by **fuko** » Mon Mar 10, 2008 12:31 am

This site has a good walkthrough with better diagrams:
http://www.mameworld.net/pc2jamma/arc_sat1.html

The only problem with this setup, as has been pointed out, is the RGB levels that the Saturn puts out are lower than those your arcade monitor is used to, so it may end up looking a bit washed out. There was a fellow who posted a while back getting interest on an all-in-one board he designed, but I haven't seen anything since.

GaijinPunch · Post by **GaijinPunch** » Thu Mar 13, 2008 4:15 am

Hmm. For the Saturn you shouldn't need the sync separator since it outputs a proper sync signal.

Hmmm..

The LM1881 circuit isn't as simple as just soldering the chip to the comp video line. You'll also need a couple capacitors and a resistor in the mix.
This should help with how to read the schematic:
http://www.kpsec.freeuk.com/symbol.htm

Maybe I should continue to use my XRGB-2. I don't have even close to the time fuck w/ a modding cables right now. And it sounds like there's going to be some fidgeting going on to get it to work right, no?

fuko wrote:This site has a good walkthrough with better diagrams:
http://www.mameworld.net/pc2jamma/arc_sat1.html

The only problem with this setup, as has been pointed out, is the RGB levels that the Saturn puts out are lower than those your arcade monitor is used to, so it may end up looking a bit washed out. There was a fellow who posted a while back getting interest on an all-in-one board he designed, but I haven't seen anything since.

I've not really gotten to play the consoles on it yet, so don't know. I hooked up a modded PC-Engine (w/ an amp) and it was lovely. Thanks for the link!

I guess I'm a bit confused. I'll try adjusting controls on the monitor, but something tells me that's not it as my PCBs work like a champ. The colors on the Saturn don't seem off at all, for what it's worth.