What's Wrong with my Sega Saturn's RGB output on my D32e1wu?

[crippling-ebay-debt]

My Setup

Low hour Sony BVM-D32e1wu unit, but can't speak to if the tube was ever replaced. RGB is provided to the monitor via RGB scart cables obtained from retrogamingcables.co.uk. All outputs including sync are now terminated with a 75 ohm cap per discussions in this thread, but my problem persists.

https://imgur.com/OBUlSqx

What's going on

Everything RGB I've been able to throw it at so far SNES, Super Famicom, Sega CD, and the Sega Megadrive look great for the most part (all CSYNC). OG Xbox, Gamecube, Wii U, PS2/PS3 all look flawless as well over YPbPr. Some examples...

Super Famicom
https://imgur.com/S2Lntj7
https://imgur.com/I3Gl2lT
https://imgur.com/c795tSt
https://imgur.com/ERsQSWJ

(Some strange artifacts are visible at times, but overall nothing too distracting)

SNES
https://imgur.com/f5FC0oM
https://imgur.com/aLXoBmU

Megadrive
https://imgur.com/dqhP1Wp
https://imgur.com/Gumq459
https://imgur.com/z7pIUQj

Sega CD
https://imgur.com/VngNZgu
https://imgur.com/LmVwgLJ
https://imgur.com/SOLBbxy

However, my NTSC Sega Saturn does not look well at all...

There are weird bands of color all over the image which is really distracting during gameplay especially on dark screens.

https://imgur.com/rGKn0th
https://imgur.com/rdiiAbC
https://imgur.com/f4L417E
https://imgur.com/3zTOYva

Conclusion

I'm at a loss here. The unit appears to be solid based on its performance with other RGB inputs (as well as YPbPr), but there is something with the Saturn it does not like. I've tried two different Saturn units while debugging (a model 1 and a model 2) with the same results. I have tried a Sync on Luma Saturn cable from retrogramingcables.co.uk and a CSYNC Saturn cable from insurrection industries as suggested in this thread as well to the same results. My previously unterminated sync cap does not seem to have yielded any results either as noted previously.

I'm pretty new to the RGB scene so any input you guys could give would be appreciated greatly! This is also my first post here on shmups so I apologize if the format of this post is low quality. I initially posted this to r/crtgaming and was given a suggestion to try here so here I am.

[RGB0b]

I'd try another Saturn cable first, just to make sure: https://insurrectionindustries.com/prod ... art-cable/

[fernan1234]

I'd also recommend trying another cable, specifically one wired for the Saturn's native CSYNC. Also, Saturn may be one of those systems where PAL vs NTSC makes a difference for cabling.

BTW, while it seems to not be required, I'd suggest terminating the sync line on the monitor as well.

[crippling-ebay-debt]

I'd try another Saturn cable first, just to make sure: https://insurrectionindustries.com/prod ... art-cable/

Thank you for your reply and for linking a specific cable! I was put off by the retrogamingcables Saturn rgb scart cable as a sync on luma cable as I would’ve preferred csync, but not knowing any other decent alternatives I decided to roll with it since my research indicated that my BVM shouldn’t have a problem with sync on luma. I guess we will find out if that’s the issue when the csync cable arrives. I’ll post an update at that time. Thanks again!

[crippling-ebay-debt]

I'd also recommend trying another cable, specifically one wired for the Saturn's native CSYNC. Also, Saturn may be one of those systems where PAL vs NTSC makes a difference for cabling.

BTW, while it seems to not be required, I'd suggest terminating the sync line on the monitor as well.

Yea I believe Saturn is one of those cases where the region matters. Retrogamingcables offered a sync on luma cable for the Saturn for compatibility with PAL systems, but claimed it should work with NTSC as well. They haven’t stocked csync cables for the Saturn in some time for whatever reason. I have a csync cable on the way from insurrection industries...hopefully that fixes it.

I also purchased a terminator cap for the sync output as you suggested. I’ve been putting it off since it didn’t seem to be causing me any issues this far, but you are right it should be terminated.

Thanks for the support on this!

[Fudoh]

You D32 doesn't usually require csync, does it? I don't think so.

PAL Saturn don't output CSYNC. If you use a NTSC CSync cable on a PAL Saturn, you're pumping 12V into the sync line. Not a good idea. Luma as sync should be fine.

Saturn cables tend to do weird things with ground though, so I would check which pins ground is connected to on your scart cable and then check if the same pins are picked up through your Scart to BNC adapter cable.

[crippling-ebay-debt]

You D32 doesn't usually require csync, does it? I don't think so.

PAL Saturn don't output CSYNC. If you use a NTSC CSync cable on a PAL Saturn, you're pumping 12V into the sync line. Not a good idea. Luma as sync should be fine.

Saturn cables tend to do weird things with ground though, so I would check which pins ground is connected to on your scart cable and then check if the same pins are picked up through your Scart to BNC adapter cable.

I can see how it could get confused since I started talking about PAL, but I’m dealing with an NTSC Saturn. It’s just that retrogamingcables.co.uk (where I got all of my other cables) only had a sync on luma cable for the Saturn since it’s supposed to work with NTSC with the added benefit that it gets around csync issues with PAL systems like you mentioned so that’s how PAL entered the discussion.

I’m in agreement that my D32 should not require csync based on what I’ve read but all of my other systems which use csync cables look great, and the one sync on luma (Saturn) is the one with the issue. Very well could be a red herring (probably is), but I’ll guess I’ll know for sure in a couple days when my csync cable gets in.

Checking the pin outs for ground is a good suggestion. I’ll give that a go Fudoh and post an update. Thanks for the input!

[NewSchoolBoxer]

I’m in agreement that my D32 should not require csync based on what I’ve read

I looked and searched through the manual: https://www.manualslib.com/manual/15938 ... 4e1wa.html

No mention of accepting RGB sync on green so not hard to assume it only has circuitry for external csync. Can pull sync from luma or composite video but rest of signal becomes interference. Other possibility is RetroRGB Saturn page shows horizontal bars from lack of 220 uF capacitor on sync line, meaning to say not all modern Saturn cables would include it: https://www.retrorgb.com/saturn.html

[SuperSpongo]

Little off-topic, but based on your username, did you buy the 7000 dollar one on ebay US?

To contribute a little to the topic: the D32 accepts Composite Video as sync just fine.

[fernan1234]

No mention of accepting RGB sync on green so not hard to assume it only has circuitry for external csync.

It can take RGsB. You just set it to internal sync instead of external sync. Can be done on the given channel settings or toggled with one of the buttons on the control unit. YpPbPr also uses internal sync obviously.

Little off-topic, but based on your username, did you buy the 7000 dollar one on ebay US?

lol I just noticed OP's username. Seems like a good guess.

[crippling-ebay-debt]

Little off-topic, but based on your username, did you buy the 7000 dollar one on ebay US?

To contribute a little to the topic: the D32 accepts Composite Video as sync just fine.

Aha no definitely too rich for my blood. I prefer to nickel and dime myself to death “with all the great deals that I will totally resale and make a profit from” and then just end up keeping haha...well that and collecting for Mega drive / Sega CD / Saturn / Dreamcast.

In regards to composite video sync if this CSYNC cable I have arriving on Saturday doesn’t shake out I can look into it, hoping that will solve my problems but we will see how my luck plays out.

[RGB0b]

Sorry, I'm just coming back to this - You'd DEFINITELY want to use a 75ohm terminator on the sync line, regardless of what sync method you're using. csync or luma as sync should be fine.

[crippling-ebay-debt]

You D32 doesn't usually require csync, does it? I don't think so.

PAL Saturn don't output CSYNC. If you use a NTSC CSync cable on a PAL Saturn, you're pumping 12V into the sync line. Not a good idea. Luma as sync should be fine.

Saturn cables tend to do weird things with ground though, so I would check which pins ground is connected to on your scart cable and then check if the same pins are picked up through your Scart to BNC adapter cable.

I can see how it could get confused since I started talking about PAL, but I’m dealing with an NTSC Saturn. It’s just that retrogamingcables.co.uk (where I got all of my other cables) only had a sync on luma cable for the Saturn since it’s supposed to work with NTSC with the added benefit that it gets around csync issues with PAL systems like you mentioned so that’s how PAL entered the discussion.

I’m in agreement that my D32 should not require csync based on what I’ve read but all of my other systems which use csync cables look great, and the one sync on luma (Saturn) is the one with the issue. Very well could be a red herring (probably is), but I’ll guess I’ll know for sure in a couple days when my csync cable gets in.

Checking the pin outs for ground is a good suggestion. I’ll give that a go Fudoh and post an update. Thanks for the input!

So as you may have already guessed, it doesn't look like my CSYNC cable did anything for me, unfortunately.

I did finally got around to taking a look at the innards of both my Saturn SCART cable and SCART to BNC adapter, however, and put a multimeter to it (continuity check) and everything appears properly grounded to me as far as I can tell on my Saturn SCART cable.

On the SCART to BNC Adapter Pin 14 (Data Signal Ground) doesn't appear to be passed through...would that be an issue?

Attached are some photos of the inner workings of my cables for reference.

SCART

https://i.imgur.com/fw0y4ko.jpg - Pins 2-20 (left to right)
https://i.imgur.com/vnn3Bxf.jpg - Pins 19-1 (left to right)

SCART to BNC

https://i.imgur.com/mPcCBLd.jpg - Pins 1-19 (left to right)
https://i.imgur.com/fncBCxG.jpg - Pins 20-2 (left to right)

The SCART to BNC cable is sort of a mess with all of the glue everywhere, but we basically have ground from all the cables on the BNC end twisted together and connected to Pin 18 (blanking signal ground) which then connects to Pin 21 (shell/chassis). We also have Pin 4 (Audio Ground), Pin 5 (RGB Blue Ground), Pin 9 (RGB Green Ground), Pin 13 (RGB Red Ground), and Pin 17 (Composite Video Ground) daisy chained in the order listed to Pin 21 (shell/chassis). Nothing connects to Pin 14 (Data Signal Ground) as mentioned previously.

I obtained my SCART to BNC adapter from retrogramingcables.co.uk is there an alternative anybody would recommend? I don't know if mine is of the highest quality.

[crippling-ebay-debt]

Sorry, I'm just coming back to this - You'd DEFINITELY want to use a 75ohm terminator on the sync line, regardless of what sync method you're using. csync or luma as sync should be fine.

I did obtain a 75 ohm terminator for the sync line (see updated pic in my initial post), but no dice, unfortunately. Maybe it will save me some headache with something else down the line though. I appreciate you calling attention to it!

[NewSchoolBoxer]

By process of elimination, issue stems from Saturn power supply, Saturn itself and/or Saturn RGBS cable right? Power supply least likely culprit. Assuming pin to pin wiring is correct, cable pictures look fine. I don't see capacitors but could be elsewhere in cable and maybe Saturn has them inside for RGB. If you have a multimeter that measures capacitance, can measure on cable input to output and check the sync line at least. My PS1 JP-21 cable uses pin 9 (pin 20 SCART) Composite video in for sync.

Maybe the issue is a bad capacitor in the Saturn. I say that after seeing Reddit post for stock NES that had similar bands from a 10 uF video line capacitor that had to be replaced: https://www.reddit.com/r/nes/comments/8 ... as_on_how/

That was a good call to add 75 ohm terminators. Says right in the manual to do that but I assumed was self-terminating or had manual switches. Great this forum is knowledgeable enough to verify the BVM takes all sync. I noticed the INT feature but I thought could be just for Component. My PVM manual is very specific in mentioning sync on green.

SCART to BNC Adapter Pin 14 not passed through, I don't see a single reference to pin 14 on any SCART diagram. I assume not used.

[crippling-ebay-debt]

By process of elimination, issue stems from Saturn power supply, Saturn itself and/or Saturn RGBS cable right? Power supply least likely culprit. Assuming pin to pin wiring is correct, cable pictures look fine. I don't see capacitors but could be elsewhere in cable and maybe Saturn has them inside for RGB. If you have a multimeter that measures capacitance, can measure on cable input to output and check the sync line at least. My PS1 JP-21 cable uses pin 9 (pin 20 SCART) Composite video in for sync.

Maybe the issue is a bad capacitor in the Saturn. I say that after seeing Reddit post for stock NES that had similar bands from a 10 uF video line capacitor that had to be replaced: https://www.reddit.com/r/nes/comments/8 ... as_on_how/

That was a good call to add 75 ohm terminators. Says right in the manual to do that but I assumed was self-terminating or had manual switches. Great this forum is knowledgeable enough to verify the BVM takes all sync. I noticed the INT feature but I thought could be just for Component. My PVM manual is very specific in mentioning sync on green.

SCART to BNC Adapter Pin 14 not passed through, I don't see a single reference to pin 14 on any SCART diagram. I assume not used.

Hey NewSchoolBoxer thanks for taking the time to put some considerable thought into debugging my issue!

So the fact that I’ve tried two different cables one cysnc and one on luma and checked the wiring and continuity I think we can rule out the cables at least in regards to sync or grounding. Also since the cable I showed was sync on luma, the capacitor and resistor called for on the csync line would not need to be present is my understanding. I also think we can rule out the SCART to BNC adapter since it appears to be grounded properly, works for all my other systems, and there is really nothing going on in there.

Furthermore, I recently had an opportunity to hook up my Saturn to a Sony PVM-1910 with the same cables and everything looks fine so you think that would leave my TV as the delta and not the capacitors in the Saturn since I’ve tried two to the same effect on my BVM and they look fine on the 1910...that is unless my BVM is overly sensitive to something that I haven’t realized yet.

Now the kicker is I have come to discover if I mess with the H adjust and V adjust and distort the image a bit I can make the rings of color go away which is somewhat a relief, but not ideal as I lose a fair amount of available screen real estate in the process and I think the aspect ratio is slightly off. On the bright side I’ve finally got something on the screen that doesn’t make my eyes bleed! Still drives me crazy though to not understand the root cause haha

[Kez]

Seems like maybe you could get results from playing with a particular setting on your BVM. It might be worth just moving some around and see what happens! (Write the initial value down first).

I had an issue with some signals that was fixed by changing the clamping settings, detail here.