gscartsw: automatic 8:1 SCART-RGB switch

There's a competition going on right now so I won't be sharing it for obvious reasons. I was willing to share everything when it was under development but nobody really was interested. Now when it got profitable all kind of people are asking about schematics and other technical stuff . There is this guy "lotharek" who initially wanted to manufacture my switch in Europe, we talked a bit by mail and I was interested to offload some work to him but he didn't reply since, was waiting for him for a month.
Recently I've found out that he's building his own switch (with blackjack and hookers obviously ). Initially he wanted to do something different (manual switching, 2 configurable outputs some displays etc.) but according to his latest update now it's a total ripoff of my switch (automatic 8:1).
Anyways it wasn't very nice from his side just to disappear and waste my time and quietly building his own project, but well, I'm up for the competition
Although if you need technical advice and basic idea how the switching works you can send me a PM. Obviously I won't be able to guide you through everything but I can explain a basic idea and main IC's you'll want to use.

JP21 is very different, don't forget about the GND & audio pins. It was around 6 pins to interconnect, won't work.

 

Thanks for the response, and I totally get your position. It's a shame that someone could be such a turd about it to you like that. And I'll take you up on the knowledge tidbits though, which is very very appreciated, so expect a PM later today.

I'l didn't realize that the audio and ground pins would be a problem, and I'll look into that. Not personally interested in that aspect since everything I link up is euroscart, but was just generally curious.

 

I was one of the few lucky ones to get one of the leftover gscartsw's.

Just prepping for when I receive mine... Ok so based on reading other posts, it seems to Tomee Genesis 1 Power Adapter is recommended, but as far as the male scart to male scart cables goes, can I use this cable to setup the output port and XRGB Mini port?

http://www.ebay.com/itm/4-FT-Premiu...106704?hash=item1c55797210:g:l2sAAOSwMmBVk~xc

 

I have one question. I'll be home in a week and finally setting these up. I bought 2 to daisy chain. Will I need to run power to both or just the one? I have the genesis adapters for both ready but figured I should ask since I've never powered these sorts of things.

 

That should work. You may also be able to get a male SCART to XRGB cable directly from retrogamingcables.co.uk/

You'd have to power both.

 

EDIT: sorry for the confusion: As RetroRGB pointed out - you'll have to power those separately. However you can use only one power supply and this:
http://www.ebay.com/itm/311600807604

 

@superg , I'm running into an issue that I'm not sure how to solve.

With my old setup, I have my PC-Engine getting split between a PVM and going through an XSync-1 into an XCapture-1. The picture is pretty good quality. However, when I run the PC-Engine through your switch, going to the PVM from your SCART out and straight to the XCapture-1 on the VGA, I'm getting a blurred picture. On your switch, I have it set to do HV and CS, and changing these does not affect the picture. I'm attaching comparison images.

Through XSync-1:


Through your switch:


EDIT: Same results if I put the SCART out from your switch into the XSync-1, but I kinda expected that.

 

Do you experience this blur issue on both outputs (SCART/VGA)?
Is it only PC-Engine?

 

Yes. The capture device was just a more reliable source to grab an image from. Same on the PVM.

Yes. It does not affect my Saturn, Genesis, or SNES (haven't tried the Neo Geo or Jaguar yet).

To be clearer: this is a US Turbo Duo that was modded for RGB. Kept the same Duo pinout but put in a DIN-8 (the new three pins are R, G, B). There is a switch mod on the Duo to toggle what goes out on Pin 1 (composite sync or composite video). The picture always looked essentially the same in my previous setup with the toggle in either position, but with your switch it will only show an image in one of the two positions (I'm not sure which is csync and which is comp video, as I was stupid and didn't label them). I don't know if the SCART cable had a stripper installed in it or not.

Previous setup had the following:
SCART cables to a rebranded (Hama?) 3-input, manual button, non-powered switch. Output of switch -> Shinybow distributor.
Distributor path 1: BNC breakout of RGBs -> PVM
Distributor path 2: XSYNC-1 -> XCAPTURE-1

With your switch:
SCART cables to your device.
SCART output: BNC breakout of RGBs -> PVM
VGA output: XCAPTURE-1

 

I also use XCAPTURE to check the quality issues. However I don't own PC Engine and other RGB-modded stuff. Surely I wanna look into it after I'll be done with JP21 and the distribution. If you already send clean sync from your console you don't want to clean it twice (adds a bit to latency). VGA output always gets clean sync.
In general if you see more blurred picture it means that signal is weak. A good check would be to measure RGB level using oscilloscope. A lot of mods doesn't properly set a level, there is nice topic about SNES here with all the details.
P.S. Jaguar is fine, it doesn't require mods, just a cable.

 

I'd be happy to send mine over to you for testing.

What I'm curious about is why the signal was strong enough in the old setup (which had a switch and distributor), but not on yours?

 

Thanks but I don't think I'll be able to look into every "potential incorrect mod" case. When time will come I'll get that console for myself and then I may investigate what kind of mods are available and if they are properly implemented.
In the switch case the signal goes through more elements than directly, that's why.
That's only a speculation, I can't say for sure without looking into it.

 

That's fair enough. I installed the same amp that @retrorgb recommends on his site, so I'm curious as to which other methods I could use to boost the signal?
And before I go on a wild goose chase, what are the odds that the issue here is in the cable rather than the generator?

 

Which one, exactly?

The cable is always the first place I check with these things. I'll do some testing this afternoon.

 

The amp came from here: http://www.otakus-store.net/en/home/11-rgb-nec-modding-kit-for-pc-engine.html
Following the instructions here: http://www.otakus-store.net/en/content/6-guide-nec-rgb

Any advice for any testing I can do on my own? Also, and this may be a stupid question, but I'm not sure if this SCART cable was wired for csync or not. When one gets a cable that is specifically built for csync, that just means they added a stripper chip into the package, right?

 

I don't link to that one, but it looks like it uses a basic THS7314 amp, which should work perfect through the switch.

It depends. In cases like SNES and Genesis, it just means that they wired a cable to the csync output of the output port.

Let me test a few of my THS7314 modded consoles and report back...

 

Yes, I knew I had seen that specific chip on your site.

Thank you sir. Like I said, I have a toggle on the console to go between csync and comp video out on pin 1. If I use my old switch setup, flipping that doesn't seem to make any difference in image quality, but on the gscartsw8 it goes blank for one of the two positions.

 

I just tried all the consoles I own which have a THS7314 amp (including my TG-16) and all seemed to work fine.

Does the problem occur on the PVM, the XCAPTURE, or both?

 

Both. Only when run through the new switch.

 

Wow, I'm stumped. I tried the TG-mod by Low Budget (THS7314-based) and I know people who have tested the db Grafx Booster (CXA1165-based) and the one sold by mickcris and all are working fine. I'm really not sure what could be happening.