SNES Video outputs jailbars?

Hi

I thought the SNES did not suffer from jailbars like the Genesis does but my SNES does have some faint jailbars most noticeable on solid colours.

Let me first explain my setup:

- NEC Projector (Handles 15KHz sync)
- Self made SCART to VGA connector
- Hana 3 inputs SCART switch
- RGB SCART cable from Retro_Console_Accessories on eBay (tried 2 different ones from them)
- SNES 1chip model

I have the Sega Genesis and the N64 on that same Scart switch and they are both free of any Jailbars.

So do any have jailbars also on their snes? Is there a fix?

Thanks

 

Have you tried it on different displays?

also some argue that the mini SNES has a better image quality than the 1chip so if you have access to one you should try that

also check all the inside of the scart cables capacitors

 

This looks more like signal ringing than jailbars. Jailbars are caused by coherent switching noise over the power rail which gets coupled to the video signal--a very predictable pattern.

Ringing is caused by the nature of real (unideal) electrical components in the signal path--when both the SNES's output, the transmission line (the coax cable) and the projector's input aren't matched, the signal energy "sloshes" around back and forth in the wire causing video distortion.

Your wiring is suspect:
1) video game cabling is built to low standards/low manufacturing accuracy
2) switches disrupt the electrical characteristics that the cable is supposed to be built to
3) your SCART to VGA adapter undoubtedly has the wrong electrical characteristics

For very short wires none of these things affect the signal quality much, but once you start dealing with longer cables they become issues. Truthfully nothing analog is perfect, but higher end items control the electrical characteristics very tightly.

In other words for best signal quality take a VGA cable, chop off one end and wire it to a SNES connector.

 

Thanks guys for you answers. I would not be surprised if the problem were my SCART to VGA cable. I soldered it real quick and did a poor job there but it works so i left it there. It is short though, only about 1 feet and a half. But the Genesis signal and n64 both go through that same short cable and their image is crystal clear with no artifact. I have 220uF capacitors on each RGB lines, what should i expect if i bypass them? A brighter signal?I have no other way to test the RGB cable because here in Canada, SCART capable tvs are extremely rare! But like you said Calpis, making a snes to vga cable would tell if my cables/switch are good or bad depending on the results i get.

 

The capacitors aren't what I mean by electrical characteristics. It's the material, insulation and diameter of the wire etc that control the "characteristic impedance" of the cable. This along with the console's video output and the display's video input all have to be matched for high quality video.

Really you shouldn't have any capacitors inside generic adapters, unless you have a way to bypass them. Lots of consoles and equipment contain the output capacitors internally so when the signal passes through 2 series capacitors the capacitance is reduced (by half for 220 uF + 220 uF), which will lead to picture distortions (or loss of sync if this happens to composite/csync). This is especially the case with borderline (barely sufficient) values like 220 uF.

Your projector may or may not have a clamp circuit (as a TV would). In the case that it does, the capacitors in the adapter don't matter (as long as they aren't redundant to capacitors in the console), any video output circuit will work well. If your projector doesn't have a clamp circuit then any consoles which do not contain the output capacitors internally (N64 mods I've seen online) may be too bright without the capacitors in the adapter.