SCART to a Wells Gardner K7200?

Started by cutty_sark, February 13, 2004, 06:23:18 PM

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cutty_sark

Hi,
I hope someone can help me out with this:
I have a Wells Gardner K7200 arcade monitor that I've been using with my jamma setup with no problems. Now I want to build an adapter to plug my consoles into the thing via SCART. So I bought a scart splitter off ebay, lopped off the male end, and soldered the appropriate wires to the appropriate pins for my monitor pinout.
And it doesn't work.

The R, G, and B are coming through but the sync's not. Tried it with PSX, DC, and Saturn with the same result. Here is how I've got it wired up:

Scart -> K7200
------------------------------
Red Out ->          Red
Green Out ->      Green
Blue Out->          Blue
Gnd ->               Gnd
C-Sync Out ->    - H-Sync

I must be forgetting something. What else do I need to hook up to make this thing work? Do I need to connect the SCART rgb returns or the c-sync return to something?

This is my monitor's input connector:

1 Red
2 Green
3 Blue
4 Gnd
5 + V-Sync
6 + H-Sync
7 *KEY*
8 Gnd
9 - V-Sync
10 - H-Sync

Thanks in advance for any help or ideas!
~cutty

benzaldehyde

Hi,

SCART cables usually carry composite video. You'll need to strip the sync from the video and then run that to the monitor. Use the LM1881; it works perfectly.

cutty_sark

Thanks benzaldehyde,

Boy do I feel like an idiot! I knew I'd need to use one of those chips sooner or later.
Cheers,
~cutty

cutty_sark

Ok, I used the LM1881 and it works fine for PSX, PS2 and DC. But other consoles won't sync up (tried SNES, CDX, SS). I'm using retail scart cables that all worked fine for me on my old Philips CM8833 monitor (which broke).

Anyone have any idea what's wrong?

Nightmare

Ok, dunno if im allowed to post links BUT go here

http://www.arcadecontrols.org/yabbse/index.php

The Wells Gardner K7200 is a arcade monitor right? That site is full of people who are into arcades...

benzaldehyde

#5
Hmmm... sounds tricky. On your non-working cables, are the +5V (blanking) signals connected on the peritel connectors? I had a Genesis cable I had all manner of trouble with; turns out it didn't have a power connection to run the circuit. Without power, the sync signal will be blocked by the LM1881 circuit. :blink: That may be it.

cutty_sark

Well, I think I've figured it out. The CDX is working now at least.

The CDX peritel only had the Audio Ground hooked up and I was getting the ground from the shield. So I hooked the Audio ground to the shield and it works fine. Thunderforce 4 looks amazing.  :)

Now to crack open the rest of my scart leads...
Thanks for the suggestions guys.

~cutty