Connecting RGB systems without using SCART

I recently got a Sony PVM 20L5 with the proper BNC to RCA adapters.
I have noticed that the vast majority of people buy a console to SCART cable, and if they have a SCART ready display, they are pretty much all set; if you have more than one system, then you can buy a SCART switcher; if you have a PVM you need a SCART to BNC cable.

So now lets pretend that I have the tools, skills, time and knowledge/experience to make and test any gaming video cable I want (as well as modify any video game console).

My questions is this, why can't I make an RGB cable (lets say a Sega Genesis) that ends in an RCA connector rather than SCART so I can connect that to my PVM that now has RCA connectors. Why do I need to use SCART and then another cable to change it to BNC?

Even more, if I can just make my own cable, with RCA connectors (proper cable, correct impedance and shielding) why can't I use a component switch box? (and use the composite connector for sync).

Thanks!

 

You can make these cables without SCART. It's just that most people who use RGB use the SCART/JP-21 connector as that's what most of the common upscalers and European TVs use. A PS2 RCA Component cable will output RGB on the PS1, PS2 (in RGB mode), and PS3 (in RGB mode) and can be ran to your PVM with RCA connectors. BNC is better than RCA so use that when possible.

Depending on the console and sync type you use, you will need 6 connectors for RGBS (R, G, B, S, LA, RA), 7 connectors for RGBHV (VGA; R, G, B, HS, VS, LA, RA), or 5 for RGsB (Sync on Green; R, Gs, B, LA, RA). This includes audio. You will also need to refer to a game console RGB SCART diagram to see what components the signals need. When possible, use C-Sync rather than Luma or Composite Video as sync. For mono only game consoles, just send mono audio down both audio plugs. If you can't get the plugs for some AV Multi-Outs, drill some holes on the console and run RGBS or RGBHV to RCA connectors or BNC connectors (if you have room to).

 

By looking at the cable schematics you linked, I can see that all the SCART cables have some resistors and capacitors build into them, so if I drill my consoles and install RCA plugs for RGB out, then I would have to connect those components to the connectors as well as making sure the impedance matches.
As far as sync, the monitor I will be using (PVM 20L5) does have a sync input, but from what you are saying I need to use the composite sync signal to get sync and not all the consoles will be the same so in some I might need to strip it.

 

I you don't want to drill the holes for a non-standard connector like the Nintendo multiout, you can cannibalize existing composite cables and re-purpose the connector. I floated surface mounted caps (with heat shrink) inside my NTSC SNES multiout cable that I made. I went the route of using VGA and running it to a 16 port switch. The VGA output of it runs via another custom cable to 8 pin minidin at a framemeister. If I wanted to hook up my Sony PVM to the whole network, I can just use VGA to BNC from the switch output.

 

That's clever, since VGA switch boxes are not hard to find and I can buy VGA connectors to solder them, but like you said also VGA to BNC cables are also easy to find and I could just adopt BNC for all my systems and (provided that I drill all the cases), but this will give me a common cable I can use with ANY other console I mod in the future.

 

For certain consoles like PAL GCs and any system that doesn't have C-Sync or Luma, then you will need to use a sync stripper on composite video. If C-Sync is not available but the system has Luma like the PS1, then you can just use Luma instead. I'm not familiar with your PVM so it may or may not like Luma or Composite Video as sync.

Many of the third party cables for these systems don't have all of the pins needed for RGB. Some of them break once opened. In the case of the PS1/2/3 and SNES/N64/GC, Helder sells the plugs in the marketplace and they have all pins connected. For something like the Atari 2600 and the 2600RGB mod board 9and the NES equivalent), just use RCA jacks or BNC jacks.

Btw, I like your VGA setup idea.

 

So to summarize things in simpler terms:

-We know each SCART cable is slightly different from console to console.

-The number of components in the SCART cables are so few that you could get away by directly soldering them inside the respective console (as long as you shrink wrap/ isolate them), no PCB needed.

-You could buy BNC plugs that you could mount to your console via drilling and soldering (taking into consideration the proper signals you could be drilling more or less holes depending of each system).

- Once you have a system modded properly you have 3 options:

1- Buy VGA to BNC cables, again in some cases you might need ones with H-Sync, V-Sync, Csync, depending of your monitor, but these cables are cheaper and more readily available ($5 vs $20 for SCART).
2- Connect the console directly from BNC to BNC to the Sony PVM or compatible RGB computer monitor.
3-You can use existing VGA switch-boxes such as KVM's to connect multiple consoles or if you stick to BNC only, you can get an Extron BNC matrix and directly connect the consoles via BNC to BNC cables to it, and then it's output to the desired display. This last method will also ensure that you meet proper impedance.

Thoughts?

 

Due to the size of the BNC connectors, I recommend installing RCA connectors and use RCA to BNC adapters or cables for systems where space is limited. Whichever connector you choose, make sure to solder the correct components on the jacks you install.

Seeing that BNC switchboxes with enough connectors for RGBHV and audio are not common and/or expensive, I have a workaround idea. Use a YPbPr Component Video switchbox, connect your consoles to it using RCA cables (R to Pr, G to Y, B to Pb, HS or CS to LA, and VS to RA), then run it to the PVM using RCA to BNC cables. Run audio to a separate switchbox in the same configuration. This way, every signal is on it's own separate cable to prevent crosstalk and it will be much cheaper too. If automatic switchboxes hate RGBHV and RGBS, use a manual switchbox. When using a mono audio source, run mono to both audio connectors.

Some consoles support RGBHV but need a mod to output it. The PS1 is easy (depending on mobo revision) and just requires wiring to a connector (use RCA on a PS1, not enough room for BNC). For the PS1, you can do what I'm doing: cut S-Video and Composite video from the multi-out then wire C-Sync to the Composite Video pin, H-Sync to Luma pin, and V-Sync to the Chroma pin. Consoles like the Atari Jaguar just need a custom cable.

If you go the VGA route, you can send C-Sync over the H-Sync pin. Run audio separately.

 

If it was me, I'd stick to normal scart cables. Buy a scart switch box, or build one like I did:




Then buy this for the output: http://www.ebay.com/itm/y/201435381594

To me doesn't make sense to install bnc connectors on the back of a genesis when it already outputs rgb through the din connector.

 

That's a great idea but about the Genesis thing, we meant for systems where the plugs aren't common. You can buy 8 pin DIN and 9 pin miniDIN connectors for cheap on eBay and not mod the console. It's the stuff like the Dreamcast where the plugs aren't easy to get a hold of.

 

Precisely, too many different connectors and the Dreamcast is a great example, the I am trying to find a more cost effective solution like what I originally asked and you suggested with the component switch box.

 

The Genesis was just an example, trying to figure out the best scenario, but if I use the existing DIN out then I will be stuck with Scart, I am new on this area, but maybe you can get a Genesis DIN plug to BNC or RCA for RGB out?

I could build a Scart switch box, (BTW yours looks pretty nice, good job there) but I have currently 26 consoles, 6 will stay on composite (modded from RF) the rest will be RGB when reasonably possible($$), a couple will be component and a couple more S-video. I just think that we are adding Scart to the mix for no good reason, I get it for the folks who lack the skills.

 

You have to make a DIN/miniDIN to BNC/RCA cable. I'm not sure anyone sells them. If the demand is there, I'll take a look into making and selling some or a box that has the jacks on it. The other day I made a custom RGBS to Component cable for the Genesis using a VGA cable. It didn't work too well.

When it comes to analog video, you can send the signal down whatever connector you want. Heck, you can even send RGBS and RGBHV down the molex connectors used to power older PC parts. To use certain connectors (in this case BNC), you have to make your own cable. Digital is where things get tricky...

 

I wonder if your cable didn't work well because it needs to be shielded, so for my experiment I will be using a computer printer cable (parallel) that has shield already and see how it works, maybe I can use the 240P test suite and my scope to see if there is signal loss on RGB from one end of the cable to the other.

 

My cable failed because of stupid design choices on my part. I used a good shielded VGA cable but it connected to a VGA female connector that was soldered to the Genesis RGB to Component board. The board end is where it wasn't shielded and interference occurred, causing severe ghosting and a purple tint to the screen.

I'm thinking about making some game console to BNC cables. I'll have to make one for the Genesis and see how it turns out. I don't have a PVM or a monitor that accepts BNC so I'll have to make a BNC female and 12V PSU input to SCART adapter to test it out. Any idea what type of BNC connector PVMs and BVMs use?

 

The 2 PVM's I have use BNC but you can get the standard BNC to RCA adapters

 

How about something like this?
http://www.ebay.ca/itm/Female-RGB-E...ny-PVM-Sega-Genesis-SNES-Neo-Geo/201435381594

Way simpler than trying to make a cable for each console, no?

 

That's scart, unless I am missing something. What I am trying to do is not to use scart at all.

 

I already mentioned that adapter in a post above. But the op rather hack up consoles or make custom cables

 

Excuse me but if you read the title, this was all about not using scart, please think about what you are saying before you write; if somebody is trying to go vegan you wouldn't suggest to go an eat a hotdog because is not really meat or to give up because it's easier to just eat regular food since it's more readily available.
The fact that you can't figure out ANY other way of doing this make you unqualified to come here and give an opinion in this matter, right? otherwise you would be sharing a picture of that instead.
There is nothing wrong with "hacking" a console or making a cable; I can make any cable just as good as any of those YOU have bought.