General upscaler thread

[Greg2600]

2 hours ago, newtmonkey said:

I'm still paranoid about using the SCART input as you aren't supposed to use TTL CSYNC cables with the RT5X, and I have no way of telling if any of my SCART cables are TTL.  My first RT5X was either defective out of the box, damaged in shipping, or destroyed by a bad cable (Mike Chi did replace at it no cost, for which I am eternally grateful), so I don't want to risk it, but I also don't want to go spend hundreds on all new cables just to be sure.  So for now, I will keep using the OSSC for SCART RGB, and the RT5X for composite/S-video/component.

---

In other news, I've been using the OSSC with my dedicated DOS gaming PC.  It looks absolutely fantastic, and now I can turn on the scanline filter for EGA games and pretend I'm playing them on an actual EGA card and EGA monitor :).  One issue I've run into is that the monitor drops the signal when switching from text mode (DOS prompt) to graphics mode (nearly all DOS games).  A quick press of the input button fixes it, but it's a little annoying.  I'll have to fool around with the sync settings and see if I can resolve it.  Does anyone have any advice on specific sync settings on which I should focus in troubleshooting this?

So many systems natively or via RGB boards may output TTL C-Sync; however, I believe most readily produced SCART cables usually have a voltage step down resistor on them.  If you have been using AV1 (RGB-SCART) on your OSSC, that also has a 75 ohm termination, so if you haven't blown it out, you'd be safe with the RetroTink 5X.

[Steven Pendleton]

2 hours ago, newtmonkey said:

I'm still paranoid about using the SCART input as you aren't supposed to use TTL CSYNC cables with the RT5X, and I have no way of telling if any of my SCART cables are TTL.  My first RT5X was either defective out of the box, damaged in shipping, or destroyed by a bad cable (Mike Chi did replace at it no cost, for which I am eternally grateful), so I don't want to risk it, but I also don't want to go spend hundreds on all new cables just to be sure.  So for now, I will keep using the OSSC for SCART RGB, and the RT5X for composite/S-video/component.

This is part of why I refuse to use SCART.

[+KylJoy]

I still don't have a 5x.  I can't get past the backward SCART port.  That drives me crazy.

[DJ Clae]

3 hours ago, newtmonkey said:

I'm still paranoid about using the SCART input as you aren't supposed to use TTL CSYNC cables with the RT5X, and I have no way of telling if any of my SCART cables are TTL.  My first RT5X was either defective out of the box, damaged in shipping, or destroyed by a bad cable (Mike Chi did replace at it no cost, for which I am eternally grateful), so I don't want to risk it, but I also don't want to go spend hundreds on all new cables just to be sure.  So for now, I will keep using the OSSC for SCART RGB, and the RT5X for composite/S-video/component.

I'm sorry, but someone has to defend shart, because this is nonsense. How do you not know what cables you own? If you buy from a reputable seller instead of randos on ebay this won't happen. If a scart cable is outputting TTL sync, that cable is improperly made.

 

If you're not sure, at least opening scart cables to check is an option. If you're not sure what you're looking for, open both ends and post photos.

Edited December 23, 2021 by DJ Clae

[newtmonkey]

1 hour ago, DJ Clae said:

I'm sorry, but someone has to defend shart, because this is nonsense. How do you not know what cables you own? If you buy from a reputable seller instead of randos on ebay this won't happen. If a scart cable is outputting TTL sync, that cable is improperly made.

 

1) I have a cable from Retro Gaming Cables, which is an otherwise reputable seller, that is marked "TTL csync."  Is that improperly made?  Mike Chi advised me to throw it away so that I would never mistakenly connect it to anything.

2) The labels on SCART cables from reputable sellers typically just say "cysnc" or "sync on luma." Is it safe to assume that these are properly made?

3) All of my SCART cables are from Retro Gaming Cables and Retro Access, and were made years ago when I first started getting into this.  How can I tell they are properly made?  I assume it's a matter of opening the cable up and checking for the appropriate resistor.  Is that it?

Edited December 23, 2021 by newtmonkey

[mikesk8]

Good morning, 

I have recently started with N64 and RetroTink Pro (PAL via composite cable) and wanted to get your input on something  Basically, the picture on my LCD is always 720x576 (LCD native 1920 x 1080 set to aspect ratio mode) with RetroTink, which is correct for PAL. However, the actual game size (the area the game occupies) is dramatically different between games. In the attached examples, the area is just different, but there are examples like Wave Racer that the area is from top to bottom occupied (with black borders on left/right sides). 

 

I do not know, but I was expecting the same game area across the screen. I think it was the case in the CRT times. 

Edited December 23, 2021 by mikesk8

[DJ Clae]

8 hours ago, newtmonkey said:

1) I have a cable from Retro Gaming Cables, which is an otherwise reputable seller, that is marked "TTL csync."  Is that improperly made?  Mike Chi advised me to throw it away so that I would never mistakenly connect it to anything.

2) The labels on SCART cables from reputable sellers typically just say "cysnc" or "sync on luma." Is it safe to assume that these are properly made?

3) All of my SCART cables are from Retro Gaming Cables and Retro Access, and were made years ago when I first started getting into this.  How can I tell they are properly made?  I assume it's a matter of opening the cable up and checking for the appropriate resistor.  Is that it?

1. It's good they labeled it. I buy from them and i don't see any TTL sync cables currently for sale on their site. TTL sync is not for consumer TV's, so yes, that cable isn't within normal scart spec.

 

2. Yes, if you trust the sellers. Sounds like they were careful about sync and labeled what they are.

 

3. Yes.

 

Sorry about what happened to your first RT5X. Mike Chi is really nice. If your cables are working with the OSSC they're probably okay.

[Greg2600]

I will defend @newtmonkey here, because the RGB/SCART world is not something most of us get into with any background, especially if you're a Yank like me who did not grow up with it.  Originally, the only thing you had to "worry" about was NTSC vs. PAL, and then whether your 21-pin was being fed the European pin set or Japanese.  The XRGB stuff obviously needing an NTSC-J cable, while the rest of the NTSC world actually used the PAL pin set.  Confusing! 

Eventually I began seeing reference to syncing, and while I'm still not sure of anything that would require sync on luma over chroma, again I was able to verify that CSYNC were the cables I needed.  So I bought ones labeled as such.  There were also different grades in shielding and such, where I could notice how thinner cabling, which still worked, produced crap over the better stuff.  But there were NO mention of 75 Ohm vs. TTL within the CSYNC category.  This only became a "thing" recently I presume with devices like OSSC and RetroTink offerings.  I'm not sure if you could even buy a TTL CSYNC unimpeded cable these days, certainly not for gaming.  I've read some of the old OEM Nintendo SCART cables could be an issue, but honestly why would you use those now?

 

Now, some sites like https://retro-access.com go out of their way to detail every last thing, including that the cables are 75 Ohm and not TTL.  https://www.retrogamingcables.co.uk still just signifies CSYNC or sync on luma, nothing much about TTL.  My cables were mostly purchased from retro access' old ebay account 7-8 years ago, and they were well labeled, but back then, as I said, they made no mention of TTL as it was not a "thing" anyone ever made mention of.  They put resistors on their cables even back then simply to eliminate interference.

 

I do not believe your SCART cables KO'd the RetroTink because they may have been unimpeded.  That was likely just a defect, which Mike rightly replaced.

Edited December 23, 2021 by Greg2600

[DJ Clae]

I'm curious what anyone would have been selling cables that output TTL sync for. What device takes TTL sync? Seems like it would have had to be someone's custom setup or a special case like that. Not something to be normally considered.

[newtmonkey]

4 hours ago, Greg2600 said:

Eventually I began seeing reference to syncing, and while I'm still not sure of anything that would require sync on luma over chroma, again I was able to verify that CSYNC were the cables I needed.  So I bought ones labeled as such.  There were also different grades in shielding and such, where I could notice how thinner cabling, which still worked, produced crap over the better stuff.  But there were NO mention of 75 Ohm vs. TTL within the CSYNC category.  This only became a "thing" recently I presume with devices like OSSC and RetroTink offerings.  I'm not sure if you could even buy a TTL CSYNC unimpeded cable these days, certainly not for gaming.  I've read some of the old OEM Nintendo SCART cables could be an issue, but honestly why would you use those now?

Thanks, that has been my experience 100%.

[Greg2600]

3 hours ago, DJ Clae said:

I'm curious what anyone would have been selling cables that output TTL sync for. What device takes TTL sync? Seems like it would have had to be someone's custom setup or a special case like that. Not something to be normally considered.

Well TTL voltage I believe is what you find in VGA, hence why the AV3 input on the OSSC is fine with it.  Nothing consumer that would use RGBS, component, S-video, composite, etc. could handle that voltage, so the resistor was put on the cables themselves.  Why not on the console?  Maybe they figured it was cheaper just to put them on cables alone, especially given that much lower % of customers would have even used a SCART cable on 8/16-bit systems out of the total sold.

[newtmonkey]

Here's an example of an SCART cable sold by a reputable seller (which happens to also be the PS1 SCART cable I own):

 

https://www.retrogamingcables.co.uk/sony-av-accessories/PlayStation-1-RGB-SCART-CABLES/sony-playstation-1-2-3-ps1-ps2-rgb-scart-cable-composite-sync-CSYNC

 

It is listed as compatible with Framemeister and OSSC, which is why I bought it a few months back for use with my OSSC.

 

Here's Mike Chi telling a user on reddit to NOT use this cable on the RT5x (likely due to it containing a sync separator), but to get the sync on luma cable instead:

 

https://www.reddit.com/r/retrogaming/comments/q5r8i5/retrotink_5x_scart_compatibility/

 

Now, Mike indicated while troubleshooting my unit that plugging in an out-of-spec SCART cable shouldn't immediately destroy the SCART input (unless something is seriously wrong with the cable), but instead would result in damage over time.  Still, it's a very confusing situation imo.  When the manufacturer of the device is telling you not to use cables that have been "fine" for the FM and OSSC for years, it's only natural to become paranoid about what cables you plug into the device.

Edited December 24, 2021 by newtmonkey

[DJ Clae]

I'm curious why he said not to use the CSYNC one. That's the PS1 cable that I own.

[phoenixdownita]

Some details on the whole TTL CSYNC vs 75ohm:

https://ianstedman.wordpress.com/2016/07/06/synchronise-your-video-engines/

some details on some Scart cables:

http://members.optusnet.com.au/eviltim/gamescart/gamescart.htm

 

and the LM 1881 sync stripper doc here:

https://www.ti.com/lit/ds/symlink/lm1881.pdf

the way I understand it it was used quite often being cheap and plentiful and it's the one I used in my own mods (one is in the Framemeister Scart to JP21 adapter and one in a Scart-Scart connector just so I could add the Sync Stripper to be used against a single/lonely Scart TV I have around) .

If you do not have PAL consoles (from the above list on the Scart cables, not in general), sync strippers are powered by 5V (there just isn't 12V available at the connector and I've never seen Scart cables with Sync Strippers and the need of a separate 5V power source, but they may exist).

In that case let's take the mentioned LM1881, at 5V its TTL CSYNC output can be as high as 4.5V (at 40uA) or also 3.6V (at 1.6mA), which means depending on how much current the LM1881 has to send out the CSYNC its voltage drops.

Only Mike can tell how much the Tink5X drains, but assuming the component pin at the Tink5X has a 75ohm equivalent load it means 4.5V/75ohm= 60mA ... but we already know that at 1.6mA the LM1881 would drop to 3.6V which gives 3.6V/75ohm= 48mA ... and as we know 48mA != 1.6mA and it seems the LM1881 can source max 10mA from the doc, aka a 75ohm equivalent load could only see 750mV of drop ... 

 

Attention that PAL consoles Scart cables in some cases (SNES but there are others) have access to 12V and if that is used to power the LM1881 then it can output all the way to 11V ... but again can only source 12mA ...

 

In short if you read Ian Steadman doc it tells you how by using even just a voltage divider (he suggests 330ohm for CSYNC 75) by virtue of cutting the signal amplitude by 80% (with the suggested 330ohm) makes it so a 5V signal is now a 1V signal on the downstream input pin (Tink5X in our case).

The math above already tells you it is not gonna be a 5V to begin with, if really an LM1881 can only source 10mA you already only have 750mV of possible drop over a 75ohm equivalent load.

 

Does the above mean all sync stripper circuits are "safe"? Not really, but I'd like Mike to at least bench test the classic LM1881 configuration over a 75ohm load and measure voltage drop to put this to rest (for other sync strippers the output may be much higher but they also are limited by the max current they can source, as shown at 48mA over a 75ohm load the voltage drop is 3.6V).

I used naked LM1881 CSYNC against the FrameMeister and even direct to Scart TV (a Samsung 19" LCD of 2005-ish) mostly to "fix" the NeoGeo AES (it just wouldn't sync) and a temperamental SMS, I installed it through a switch so I can use the console composite signal or the sync stripped as needed, I only recently added a series resistor following Ian write-up but had not had the time to test it (I went for a 100/150 ohm instead of 330, I figured if 75ohm is already at the destination, just adding another 75ohm series already cuts in half the voltage downstream, and if the story is really about 5V vs 3.3V that'll do already as the new max would be 2.5V at most, I sense there's more to it given the current limitations anyway). 

 

Granted if you already have a 75ohm compatible CSYNC all the above is moot, but it is possible that if really Sync Strippers can source more than 10-20mA, it means that anything that is equivalent to a 75ohm load can only see 750-1500mV drop, it also mean the Sync Strippers are supplying max current and that may not be too good for the Sync Stripper, still the downstream system should not see anywhere near 5V based on the the above data.

 

 

[Steven Pendleton]

^ and that's the main reason that I only use YPbPr except on Dreamcast.

[phoenixdownita]

15 minutes ago, Steven Pendleton said:

^ and that's the main reason that I only use YPbPr except on Dreamcast.

well also std Scart RGB+composite when it works it's just fine.

 

The issue is that some console composite output is "bad" ... or if you will enough out of spec/noisy that trips the sync detection stages of the FM, but likely others upscalers even the Tink5X seems to have some issue with some SMS and some AES, it's literally on the advisory notices:

 

"Known Issues that are Under Investigation

Sega Master System may have sync problems.

NEOGEO AES systems may have sync problems, although the latest firmware has improved this in many some cases, especially when paired with the HD Retrovision cables. For dedicated NEOGEO use, we still recommend a MVS-1C based setup as those have no problems."

And to be frank about the Tink5X even mentioning SyncOnLuma aka Y of the Y/C signal (SVideo) is a little misleading as it is not that common on consoles to begin with, either composite or CSYNC are really the only ones around when RGB is involved (and a rare SyncOnGreen that I've seen exactly once on the PS2 Linux for its VGA mode, so again not exactly Scart RGB).

[Steven Pendleton]

32 minutes ago, phoenixdownita said:

well also std Scart RGB+composite when it works it's just fine.

 

The issue is that some console composite output is "bad" ... or if you will enough out of spec/noisy that trips the sync detection stages of the FM, but likely others upscalers even the Tink5X seems to have some issue with some SMS and some AES, it's literally on the advisory notices:

 

"Known Issues that are Under Investigation

Sega Master System may have sync problems.

NEOGEO AES systems may have sync problems, although the latest firmware has improved this in many some cases, especially when paired with the HD Retrovision cables. For dedicated NEOGEO use, we still recommend a MVS-1C based setup as those have no problems."

And to be frank about the Tink5X even mentioning SyncOnLuma aka Y of the Y/C signal (SVideo) is a little misleading as it is not that common on consoles to begin with, either composite or CSYNC are really the only ones around when RGB is involved (and a rare SyncOnGreen that I've seen exactly once on the PS2 Linux for its VGA mode, so again not exactly Scart RGB).

Yeah no I literally only use HD Retrovision except on Dreamcast, where I use the Sega VGA box. SCART = do not want, and since I have the SSDS3, I also use HD Retrovision on my SuperGrafx. I have no other systems that don't have native RGB output aside from my Intellivision, but that doesn't work here anyway since apparently Japanese CRTs don't like US RF signals.

[DJ Clae]

5 hours ago, Steven Pendleton said:

^ and that's the main reason that I only use YPbPr except on Dreamcast.

You're assuming that your component cables are built correctly, and don't have any of the signals too strong or weak. You're trusting HD Retrovision like I trust Retrogamingcables.

[Steven Pendleton]

31 minutes ago, DJ Clae said:

You're assuming that your component cables are built correctly, and don't have any of the signals too strong or weak. You're trusting HD Retrovision like I trust Retrogamingcables.

The difference is that improperly built RCA cables can't damage your equipment like SCART can. Just buy new ones and it's good. I also have some PowerA garbage that I can use if I need to.

Edited December 24, 2021 by Steven Pendleton

[DJ Clae]

1 hour ago, Steven Pendleton said:

The difference is that improperly built RCA cables can't damage your equipment like SCART can. Just buy new ones and it's good. I also have some PowerA garbage that I can use if I need to.

I'd rather send pure RGB to the upscaler. With YPbPr there's a conversion step.

 

If only General Upscaler himself would show up to his own thread and straighten this out.

Edited December 24, 2021 by DJ Clae

[Greg2600]

If you mean Mike, he's normally on the shmups forum, where the clientele is often way above my head.

 

https://shmups.system11.org/viewtopic.php?f=6&t=67984

 

As for sync on luma, I don't have a great technical explanation for newt but again, I purchased from Retro Access and they've only sold NTSC with sync on luma for Saturn, PS1, and a few other systems while some like the Genesis are CSYNC.  So that's what I've gotten already. 

Edited December 24, 2021 by Greg2600

[Steven Pendleton]

10 hours ago, DJ Clae said:

I'd rather send pure RGB to the upscaler. With YPbPr there's a conversion step.

 

If only General Upscaler himself would show up to his own thread and straighten this out.

Converters are the other part of the reason that I don't use SCART. I want a single cable that works on my NTSC CRT, my OSSC, and now the RT5X. Since we don't have SCART in NTSC countries, or it's so rare here that I never heard of it until 2019, and the best input on my CRT is YCbCr, component is the best option for me, as it works on everything I have aside from the Framemeister, but that thing is kind of pointless now that the RT5X exists.

[phoenixdownita]

13 hours ago, Greg2600 said:

If you mean Mike, he's normally on the shmups forum, where the clientele is often way above my head.

 

https://shmups.system11.org/viewtopic.php?f=6&t=67984

 

As for sync on luma, I don't have a great technical explanation for newt but again, I purchased from Retro Access and they've only sold NTSC with sync on luma for Saturn, PS1, and a few other systems while some like the Genesis are CSYNC.  So that's what I've gotten already. 

Saturn and PS1 and a few other systems that do support Svideo (Y/C) output simultaneously with RGB (yeah Nintendo made a mess on that front)  have Y available and given Composite=Y+C using Y alone for the sync can give an improved picture (depending on how bad the Composite is to begin with).

Here https://gamesx.com/wiki/doku.php?id=av:playstationav even mentions wrt PlayStation that using Composite as sync may create cross-hatching so either put a Sync Stripper (LM1881) or just use the available Y.
Note that even if Y is better than Composite, a properly attenuated CSYNC is technically even better as it drops all info except sync.

Wrt Nintendo peruse https://gamesx.com/wiki/doku.php?id=av:nintendomultiav for their mess.

 

 

And just to close the loop note that Y is literally the old B/W signal before color was added in (minus a small adjustment in frequency).
Many consoles do not support SVideo as such there's no Y to tap from, only Composite (SMS, Genesis, AES are in that boat for their RGB).

I have never checked an official PS1 Scart cable to see if it uses Composite or Y as both are available, I know I used Scart on a Commodore 1084 with no issues whatsoever bitd but it could have been either and I would have not known.

 

6 hours ago, Steven Pendleton said:

Converters are the other part of the reason that I don't use SCART. I want a single cable that works on my NTSC CRT, my OSSC, and now the RT5X. Since we don't have SCART in NTSC countries, or it's so rare here that I never heard of it until 2019, and the best input on my CRT is YCbCr, component is the best option for me, as it works on everything I have aside from the Framemeister, but that thing is kind of pointless now that the RT5X exists.

YCbCr/YPbPr was really a thing once HiDef started to make the rounds (starting with 480p but compelling only after HDTV was out imho), and the Framemeister can handle it just fine via its D-terminal at the back (and you can easily find component-to-Dterm cables), I used it with a PS2 and 480 i/p worked but going from memory PS1 games did not fare as well as they are at 240p (been a while to be frank so can't recollect the details), I think the D-terminal input has support for 720p and 1080i but don't quote me on that as I have not tried them, all of my TVs at the time supported native Component so the D-terminal experiments were more for fun, there's only 1 PS2 game that supports 1080i [GT4 which I was able to try direct to TV] and none at 720p, GCN/Wii are 480p, so that leaves really only the XBOX OG with quite a few 720p and a dozens or so 1080i and again the few I had I tested direct to TV.

[Steven Pendleton]

2 hours ago, phoenixdownita said:

YCbCr/YPbPr was really a thing once HiDef started to make the rounds (starting with 480p but compelling only after HDTV was out imho), and the Framemeister can handle it just fine via its D-terminal at the back (and you can easily find component-to-Dterm cables), I used it with a PS2 and 480 i/p worked but going from memory PS1 games did not fare as well as they are at 240p (been a while to be frank so can't recollect the details), I think the D-terminal input has support for 720p and 1080i but don't quote me on that as I have not tried them, all of my TVs at the time supported native Component so the D-terminal experiments were more for fun, there's only 1 PS2 game that supports 1080i [GT4 which I was able to try direct to TV] and none at 720p, GCN/Wii are 480p, so that leaves really only the XBOX OG with quite a few 720p and a dozens or so 1080i and again the few I had I tested direct to TV.

Yeah, I thought about getting the converter for the d-terminal input for PS2, but I decided to be boring and cheap and I ended up just connecting the PS2 to the OSSC and then connecting the Framemeister to the OSSC using the Framemeister's HDMI input to deinterlace it. Then a week later I got a Japanese 60GB PS3 from the same dude I bought my Framemeister from, so it got relegated to just Dreamcast S-video. Then I got the RT5X and the Framemeister went back in its box. Then I got the VGA box a few months ago and the OSSC came back into regular service.

 

I do have d-terminal on my Trinitron, but I've never used it. My Trinitron was made in 1999 (or maybe it was 2000. I kind of forgot lol), which puts it at just the right timing to have an optional widescreen mode (which is admittedly almost completely useless now, although I suppose I can play Panzer Dragoon Zwei on it in anamorphic widescreen if I really wanted to), YCbCr, S-video, d-terminal, composite, RF, and completely lack RGB. Apparently finding JP21 on older Japanese consumer sets is not completely unheard of, but I guess they started dropping them and I'm not sure when.

 

Eventually I plan to move away from scalers and line multipliers entirely and just use the CRT, but given my current setup at this point, it's much easier to just sit at my desk and use my monitor + OSSC/RT5X than it is to sit on the fake wood floor awkwardly to use my 100% definitely not calibrated CRT.

 

aaaaaaaaaaaaaaaaand I totally just realized that I have no idea what I will do for Dreamcast once I get everything set up. Maybe just continue to use VGA + OSSC if the HD Retrovision Dreamcast cable doesn't exist yet. They are apparently focusing on keeping everything in stock during the parts shortage instead of working a lot on the Dreamcast cable, which is a very logical financial decision. I could just use S-video, though, since Dreamcast has pretty good S-video and I have the cable for it already.

Edited December 25, 2021 by Steven Pendleton

[phoenixdownita]

On 12/25/2021 at 1:51 AM, Steven Pendleton said:

....

 

aaaaaaaaaaaaaaaaand I totally just realized that I have no idea what I will do for Dreamcast once I get everything set up. Maybe just continue to use VGA + OSSC if the HD Retrovision Dreamcast cable doesn't exist yet. They are apparently focusing on keeping everything in stock during the parts shortage instead of working a lot on the Dreamcast cable, which is a very logical financial decision. I could just use S-video, though, since Dreamcast has pretty good S-video and I have the cable for it already.

Wonder if this can be convinced/coerced to work:

https://www.retrotink.com/product-page/rgb2comp

 

I have one, I bought it with my RetroTink2x-Multi to have Scart input support (I have no modded consoles or fancy cables with YPbPr output, unless it was supported originally by the console like the Wii, OG Xbox, PS2) but the data states that it accepts 240p/480i/288p/576i/480p/720p/1080i and custom resolutions (the manual even mentions an 1080p ... https://www.dropbox.com/s/rnoxcaxaqljq018/Transcoder Manual.pdf?dl=0 [link directly from RetroTink website, not mine]) .

 

Here, the "mated" 2x-M + RGB2COMP:

I was planning on keeping it (the RGB2COMP) and use it as a "second" Scart input over the RetroTink5x YPbPr section which I have no use for otherwise (again the Wii/OG Xbox are the exception there [my 360 was always HDMI enabled]).

 

Once more the output of the RGB2COMP and the input of the Tink5X line up, but yeah it's a little bit unneeded.
(BTW minor nitpick but I think the SVideo input on the Tink5X should have been put on the other side of the audio, right after R and shift down all the rest one RCA connector down) 

I am sure that for the Dreamcast VGA to "work" it'll require you to combine the H/V sync into 75ohm CSYNC but maybe Mike can weigh in on that front  

 

https://www.retrorgb.com/building-a-passive-sync-combiner.html

(whether the above AND version work, or even the XNOR variation, depends on what the full chain does)

QQ: why do people think the Scart connector is upside down? If you have the console with Scart output in front of the Tink5X it works perfectly. I guess if you want a Scart switch N-in-1 then you'd likely want the cable to go towards the back of the Tink5X so the N input would be either on top or at the bottom, is that it?