Making a RGB SCART -> VGA cable for a JPAC

[bimm25i]

So I have been looking at making a "SCART Input" for my jamma arcade cabinet.

I already have a jpac, and I d like to use it to take the video in for it's built-in sync range failsafe as well as it's video signal amps. Also I have a 12v audio amp wired through the jpac so this will let me use a kvm with output hooked to the amp and jpac to jump between a pc and a plugged in console at a buttonpress

I have purchased an EL4583 IC and a female scart port and a female vga port and a breadboard

I am only interested in accepting RGB video through SCART, any consoles that would be attached would be rg b modded, or naturally able of sending rgb over scart.

I know where to hookup r,g,b,ground,c-vid,5 volts, hsync,vsync, but I dont know what circuit the el4583 requires besides these inputs. are there other requires components? Can someone give me a MS Paint diagram of what I need to do ? Any assistance is appreciated, pics will be posted upon success

[mvsfan]

I dont know much about that Sync seperator ic. You can always look up the Datasheet for it it should tell you how to set it up.

curious, why arent you using an Lm1881? its setup is well known and straightforward.

btw, it sounds like you have the right idea otherwise, about adding a scart input to your arcade cabinet.

about that VGA switch - Kramer probably makes one that can be switched by contact closure, that has a phoenix connector for it. that way you could switch to the scart, by pressing an arcade button on the outside your cabinet.

edit: Like this one. http://www.ebay.com/itm/KRAMER-TOOLS-VP ... SwPh5ZDQ1M

[bimm25i]

I dont know much about that Sync seperator ic. You can always look up the Datasheet for it it should tell you how to set it up.

I have pulled the datasheet, but I am unfortunately not well trained enough to turn that chip diagram into a properly grounded and terminated circuit
(or at least confident enough to try plugging it in it without a little bit of guidance)

curious, why arent you using an Lm1881? its setup is well known and straightforward.

I am trying to run the JPAC now sending c-Vid down the H-sync pin on the jpac vga input and it just doesn't accept it. I am wanting to send the JAPC a true h sync and v sync separated signal so it processes the image well for me. I am also kind of hoping that i can get a guncon working once everything is connected and that means I need me some good sync.

FWIW, I am making a LM1881 circuit for a direct scart->jamma adapter but i would rather use the JPAC for this particular application pretty much to make sure the dreamcast doesn't fry my monitor when i plug it in and accidentally send 31khz to the screen

and I am just going to use a generic KVM for the switching to the JPAC/audio amp. pretty straightforward + cheap+ self contained solution for the switching


there is a picture in the spoilers tab of what i've figured out so far, and I am aware that it looks like it was drawn by child,

Is it ok to bridge all the grounds like i have drawn in the awful picture? Are there any components I'm missing?

Spoiler

[bimm25i]

So if there are no objections to my crudely drawn circuit diagram, I am gonna make this circuit tonight. here's hoping I don't fry my chip!!

[bimm25i]

So I didn't make the el4583 circuit tonight, but I did make a lm1881 circuit and attach it to this
https://m.ebay.com/itm/PCB-Advance-JAMM ... 2243258281?

I took the cvid from scart and ran it through the lm1881 circuit and took the c-sync output from that and ran it to the jamma sync pin.

I jumped a headphone jack to the l/r audio pins on the scart socket and plugged it into a 12v amp, works like a charm. Only bummer is I found out my subwoofer is bad, it's showing infinite resistance on the multimeter.

[bimm25i]

FAILURE!

so I tried wiring my circuit as shown but I just get a screen.

Back to the lab..

[bimm25i]

I checked my soldering work and it looked ok, it matched my circuit doodle above, anyone know why I'm not getting a signal?

[bimm25i]

So I keep seeing this thing called a JNX EL4583 Sync Separator but they aren't available for sale. Anyone have the schematic? It looks simple enough