Vertical lines on Saturn and N64 RGB

[Corredor X]

I have a model 2 USA Saturn that shows thin vertical lines on some colors (mostly red and light blue) when used with RGB cable, on a CRT TV/monitor and even on LCD screens with the GBS-8200 scaler and a sync cleaner. I've read on a site - RetroRGB, I think - that it happens when the c-sync is used, but I tried both it and composite video lines as the sync and nothing changes. I've soldered all grounds together on the scart end, originally it had only the audio and composite ones wired, and nothing change also. The scart also has no eletronic components on it, so I tried a 220uf capacitor and a 75 ohns resistor on the sync line, alone and together, and even so no change at all. Is there anything I can do to get rid of those lines? They are barely noticiable, but it's a pity such a nice image be plagued by them. I once get rid of the first Mega Drive ones by cutting a leg on the video chip as a online tutorial described, is there a similar operation for the Saturn?

I also have a similar problem with my USA N64. Some years ago I bought a RGB cable for it that had the THS7314 mod inside of it. It worked well at the time, image was nice but it had some thicker vertical lines/jailbars at some colors - that MK4 background that has flames on a window looked awful, for example, and some Majora's Mask textures were also affected. Messing today with the Saturn, I remembered it (haven't touched the N64 in years, sadly) and opened the cable plug to try to change the composite video to c-sync or even the luma(?) signal like someone suggested online, thinking it could be the problem, but only got a blue tinted screen with it... That's when I discovered that the *&%@# THS7314 chip that was inside the scart - soldered "leg to leg" with the resistors and wires, without any board - broke the three video legs ¬¬ I ordered a new chip and this time I'll mount inside the console with a proper board and such, to avoid future complications. But until there, what could be causing those thick vertical lines, a sync problem? Thanks in advance, guys!

[Corredor X]

Bump, any thoughts of what could be causing it?

[Fudoh]

The NTSC Saturn units output clean sync already, just standard RGB cables just don't use it. If you exchange the two pins (composite video and sync) inside the Saturn, you should be able to clear this up. Likely the same thing on the N64, but here it depends on the mod what's available on the output.

[Corredor X]

If you exchange the two pins (composite video and sync) inside the Saturn, you should be able to clear this up.

I already did it, Fudoh, not inside the Saturn but within the cable. It's all wired, so I can connect the correspondent wires of pins 1 or 8 of the console port to the pin 20 of the SCART plug. The lines appear using either one of them. Is there anything else that could be causing the vertical lines?

And I got my new N64 RGB mod board on the mail today, I'll try it later and see if the vertical lines are still there.

[Fudoh]

hmm, seems weird. The Saturn usually has a pretty good RGB picture. I have both model 1 and model 2 units and never noticed any jailbar effects on either of them.

[RGB32E]

hmm, seems weird. The Saturn usually has a pretty good RGB picture. I have both model 1 and model 2 units and never noticed any jailbar effects on either of them.

Depends upon the Saturn revision. While the XRGB-mini seems to be impervious to Saturn JBs, they are clearly visible via RGB on CRTs and the XRGB-3. Turning on the XRGB-3's LPF eliminates them at the cost of picture sharpness. The cause being that on some revisions of the Saturn the subcarrier signal trace from the VDP is too close to the RGB lines. If skilled enough, you could lift the VDP pin that outputs the SC signal, but then you'd loose chroma encoding. Not really an issue if you're only going to use RGB or don't wish to hunt down the "best" looking Saturn.

That sounds pretty awful about the N64 RGB mod, where the amp is in the cable! I've found that you will get the best picture quality if you keep the wires carrying RGB from the N64 PCB to the THS7314 as short as possible. Who's crazy idea was it to put the THS7314 in the destination end of a SCART plug?!

[Corredor X]

The cause being that on some revisions of the Saturn the subcarrier signal trace from the VDP is too close to the RGB lines. If skilled enough, you could lift the VDP pin that outputs the SC signal, but then you'd loose chroma encoding. Not really an issue if you're only going to use RGB or don't wish to hunt down the "best" looking Saturn.

That's the exact same problem that happens with the first Genesis/Mega Drive model, isn't it? My japanese one had the jailbars and I managed to get rid of it using a similar method. Can you point me the directions to do the same on the Saturn, with the right chip and pin? I've gone RGB with all the consoles and I really don't want to buy another Saturn - I got it from a great friend of mine, it's one of my favorite items of the collection.

That sounds pretty awful about the N64 RGB mod, where the amp is in the cable! I've found that you will get the best picture quality if you keep the wires carrying RGB from the N64 PCB to the THS7314 as short as possible. Who's crazy idea was it to put the THS7314 in the destination end of a SCART plug?!

Don't mention it, it was a terrible idea indeed. Bought it online from someone a couple years ago (2011, I think) but never saw another of it after. Had to buy it at the time because the THS7314 couldn't be found easily here in Brazil - still can't, by the way - and the only auctions from eBay that shipped to here just sold expensive packs of several of them. Since I already had to buy a new RGB cable for the console and the seller shipped it to here, the auction of the complete thing seemed a great deal. Little I know...

[Corredor X]

Great news regarding the N64: I fixed it

Put the new RGB amp inside the console, took the broken components off the SCART connector, wired everything using c-sync and... No game at all, just a greenish/blueish phasing image. Before messing with the cable again, used a SNES SCART I had lying here (wired for composite video) and got a nice image, but with the jailbars were still there, a little less visible but still on everything that was red. Like I read somewhere on the net, I tried wiring the Y signal (pin 7, I believe) to the sync line instead of the c-sync or composite... And it worked pretty well! The jailbars are completely gone, tried several games and no sign of them, even on colorful titles like Mischief Makers or the red logo of Zelda. One problem solved, one to go!

[Corredor X]

Sorry to bump the thread, but I still got the vertical line problem with the Saturn. Today I got Konami Antiques MSX Collection for it and the issue really shows on almost every color of it, maybe because of the lighter colors of the MSX games. I know that this might be the reason, like RGB32E said...

The cause being that on some revisions of the Saturn the subcarrier signal trace from the VDP is too close to the RGB lines. If skilled enough, you could lift the VDP pin that outputs the SC signal, but then you'd loose chroma encoding.

... but I cannot find any info regarding this procedure anywhere online Can someone point me the directions on how to do it, of which pin needed to be cut on which chip? I really want to get rid of them, the RGB on Saturn is just amazing and those lines destroy the beauty of it.

[Pasky]

I'm not familiar with that exact procedure but it sounds straight forward. Simple lift the sub carrier pin on the VDP of the saturn. You can regain chroma by wiring up a seperate 3.579545MHZ oscillator and feeding it to the encoder. I don't have a saturn so can't comment. I've only heard of that issue on Sega Genesis Model 1's with the Sony CXA1045 encoder that have that have the subcarrier oscillator directly next to the RGB signals. RGB32 might have them mixed up.

[Corredor X]

I'm not familiar with that exact procedure but it sounds straight forward. Simple lift the sub carrier pin on the VDP of the saturn.

Yeah, but I couldn't find online which is the sub carrier pin and which is the correct VDP chip (it has two, right?) to perform the mod. Just a eletronics noob that can follow directions here, sorry Like you said, I was able to do it on a japanese Mega Drive to clean it of its vertical lines, but it only worked after I also cut the (IIRC) chroma pin of the CXA1045. Can I just cut the same pin on Saturn's video encoder too? I don't mind it not having color on composite or s-video, I plan to just use it on RGB.

[Pasky]

Like I said, I think RGB32 is wrong. The CXA1045 is the encoder with this issue on the Genesis model 1, not the Saturn.

[Fudoh]

Did you actually compare the results when using composite video / composite sync / luminace (from s-video) ? If yes, what were your results ? If not, just do so.

[Corredor X]

Did you actually compare the results when using composite video / composite sync / luminace (from s-video) ? If yes, what were your results ? If not, just do so.

I didn't try luma yet, since I don't remember if the cable had it wired too, but I tried both composite video and c-sync and nothing changed, the vertical lines are the same on them. I'll see tonight if there's a way to connect it by the cable or if I have to cut and solder the board like the N64.

[Corredor X]

Fudoh, you are my hero

I tried it with luma as sync and the lines were gone! Despite doing it on the N64, it never occurred to me to do the same thing on the Saturn for the lack of connections... Since my RGB cable doesn't have wires for luma or chroma, I had to improvise a new one using a spare male SCART plug, ribbon cable and some pins. It worked flawlessly, the vertical lines just disappeared. Tried it again with Konami Antiques and every color is crystal clear. Also tried with Legend of Oasis, the game that made me notice the lines in the red Ancient triangle logo, the title screen and everytime water was present. All gone too! Now I just have to find a way to open the mini din on the RGB cable to change the wires, since it's one of those molded ones. Better than messing with the innards of the console, still.

Many thanks to Fudoh, Pasky and RGB32E!