Impossible setup: SNES>Sync Strike>Extron RGB>Sony BVM

[HelloComics]

Hello there guys. Long time lurker here.
This is hands down the most knowledgeable forum about rgb and crt gaming on the web so I wanted to share my issue with you.

This is my setup: PAL SNES (SuperCIC modded) > ArcadeForge Sync Strike > Extron RGB 203Rxi > Sony BVM G1E (sync set to EXT etc...)
Well, with this setup all I get is a rolling picture so I guess the sync is not working properly. The Extron RGB shows "No Input" on it's screen even though the BVM is displaying an image.
I also have a PC (with CRT_emudriver) connected to the Extron RGB and that displays perfectly on the Sony BVM, so those don't seem to be the problem.



Next is to suspect the Sync Strike. I use a 980mA power supply to power it (recommended over 0.5A). The light comes on it no problem.
It also works with SCART power as the light also comes on when I switch the toggle to SCART on the Sync Strike.
In either case there is no change in the rolling picture.

Then there's a weird behaviour between the Sync Strike snd the Extron RGB. When I connect the SNES to the Sync Strike I get the rolling image, but the Extron RGB still functions as normal and I can switch inputs on it etc...
But as soon as I give it power (either from the power supply or SCART) the image on the BVM doesn't change, but the Extron RGB kind of freezes.
I can no longer switch inputs and the image on screen turns black every few seconds as if it loses the input. It returns to normal after I switch off the Sync Strike and unpower/power the Extron again.

Well next is to suspect the console's SCART cable. So I purchased another one to see if that was the issue, but it had the same result.
The cables have the composite video on pin 20. I don't know if getting a cable with sync from Luma would make any difference as far as the Sync Strike is concerned.

I'm out of ideas. Has anyone connected the Sync Strike with an Extron RGB succesfully? Is this an impossible task? What do I try next?

[Syntax]

Using a cheap lm1881 stripper circuit on such an expensive monitor is your first mistake i'd say.

[HelloComics]

If the Sync Strike is not adequate, what do you need then?

[Guspaz]

The gscartsw-lite does a pretty high quality job at sync stripping. Does the BVM require csync? Why are you feeding it through an RGB interface?

[HelloComics]

Yes, the BVM requires CSYNC. I'm using the Extron unit for the input switching (it has 3 inputs) and more importantly for the horizontal and vertical centering options as every console has a slightly different positioning on the screen. The gscartsw looks awesome, but I don't need a switch and is too expensive for me at this time. Also forgot the Extron combines the H and V sync from the PC, so it serves a bunch of functions.

[AndehX]

I have a G1E and it definitely doesn't require csync....

[HelloComics]

Maybe I'm mistaken on the nomenclature, but it has only one sync input on the back card so the vertical and horizontal sync do need to be combined.

[theclaw]

Maybe I'm mistaken on the nomenclature, but it has only one sync input on the back card so the vertical and horizontal sync do need to be combined.

The monitor may support using composite video to sync.
What happens if you directly use the sync from a SNES RGB cable? That way you'll get the sync intended by Nintendo.

[AndehX]

Maybe I'm mistaken on the nomenclature, but it has only one sync input on the back card so the vertical and horizontal sync do need to be combined.

The SNES doesn't output seperate H and V sync though, so why are you trying to combine them? The sync strike shouldn't be needed at all. Just connect the SNES directly to the Extron.

[HelloComics]

There's no change in the image even when the Sync Strike is off.
You still need it though as the Extron input connectors are DE-15.
Also the Extron only admits clean sync and as I understand the PAL SNES combines the sync with the composite video signal. That's what the Sync Strike is for.

[AndehX]

can you post some photos of how you have everything connected?

[HelloComics]

I disconnected everything in fury Let me do it again and take some pictures for you.

[theclaw]

I disconnected everything in fury Let me do it again and take some pictures for you.

What I'm suggesting is to connect the sync from the SNES, right to the BVM.
Exactly as it would be done on a telly in Europe.

[HelloComics]

Here's the setup:


SCART from the SNES goes to the Sync Strike. DB15 out from the Sync Strike to the DB15 input on the Extron.


The Extron outputs R, G, B, HSync, VSync and Sync on BCN connectors.


R, G, B and Sync are connected to the BVM.

I don't have any SCART to BNC cables to test the SNES directly. And I want to connect the SNES to the Extron so I can use the centering controls and quickly switch between PC and Console.

[AndehX]

I see you have a cable connected to the H BNC terminal on the Extron. I would disconnect that as im sure the Extrons auto detect the appropriate sync signal based on whats connected to it. So if you only connect csync (S terminal) you should only get csync being output. I'd disconnect that yellow cable connected to H.

[HelloComics]

I already tried that and there's no change. I only leave it plugged there so that it doesn't get in the way.
Also note that the PC is also connected to the Extron and it works flawlessly.

[AndehX]

I know this may seem silly, but have you tried connecting Hsync to the BVM instead of S? I know it has S as a dedicated csync output, but on other models of Extron (like mine) there is no dedicated S output, so the Hsync terminal doubles as H and Csync depending on weather you have Vsync connected or not. Maybe try just connecting Hsync?

[HelloComics]

Yep, I tried all possible combinations with no luck
Again, the PC does work with the Extron. So the issue is most likely the SNES/Sync Strike situation.

[AndehX]

I'd definitely try to eliminate the sync strike from the chain and see what happens. The issue is with the sync signal, and thats what the sync strike is messing with.

[HelloComics]

I may need some type of SCART to DB15 cable then. Guess I'll do some research on that. But now that I think of it, the PAL SNES won't work either beacuse it doesn't output the clean sync the Extron is expecting. I may have to just get a Super Famicom and abandon my dream of using the PAL SNES with the Extron

[FinalBaton]

HelloComics, did you try SNES -> SyncStrike -> BVM ? as to see if the Extron is the problem and confirm if the SyncStrike works properly?

(I didn't see this setup mentionned in your OP)

[HelloComics]

That's a good idea. I already tried that but the sync doesn't work either. Thing is my DB15 to BNC cable has 5 wires I guess for H Sync and V sync. Maybe I could get a "T" BNC connector to combine those and see if there's any difference but don't have any of those on hand right now.

[FinalBaton]

That's a good idea. I already tried that but the sync doesn't work either. Thing is my DB15 to BNC cable has 5 wires I guess for H Sync and V sync. Maybe I could get a "T" BNC connector to combine those and see if there's any difference but don't have any of those on hand right now.

Normally just plugging the Hsync wire into the Sync line on your monitor should work. But yeah I guess you could try a 4 BNC to DSUB15 cable. Or a "T" connector I guess

[AndehX]

The Hsync line also carries the csync signal when you send RGBS down it.

[HelloComics]

Then the Sync Strike doesn't do it's job since I already tried the H Sync wire. The sync strike also has screw terminals, so I'll try a bare wire there as a last resort to see if it's the DB15 output that's faulty.

[HelloComics]

Ok, I tried outputting the CSYNC directly from the screw terminal on the Sync Strike. The result is the same. I even found out the image scrolls LESS without any sync signal cable connected to the BVM. So I think we can conclude the Sync Strike is not working properly.

[FinalBaton]

You should also try a straight SNES -> BVM connection

[FinalBaton]

So I think we can conclude the Sync Strike is not working properly.

Looks like you found the culprit

[HelloComics]

You should also try a straight SNES -> BVM connection

I don't have cables for that unfortunately. The SNES works perfectly connected to a regular TV and the BVM works perfectly with my PC and Extron, so I think I can rule those out as faulty. That leaves the Sync Strike as the most likely issue.

[DejahThoris]

I don't have cables for that unfortunately.

It's probably worth the $10 investment just to *know* rather than assume.