What kind of interference?evil_ash_xero wrote:Interesting. Can their SNES cables actually get rid of that interference? I get that, even with the official cables. I still get interference (not very noticeable now) on the SNES Mini (RGB modded).
I wonder if that would fix that? That's like the worst offender, when it comes to interference.
Good place to get shielded RGB cables now?
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bobrocks95
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Re: Good place to get shielded RGB cables now?
PS1 Disc-Based Game ID BIOS patch for MemCard Pro and SD2PSX automatic VMC switching.
Re: Good place to get shielded RGB cables now?
Indeed, this is very important for three reasons:maxtherabbit wrote:thicc cables are the best
1. AWG (smaller the thicker, means more copper/silver)
2. Shielding
3. Real proper 75 Ohm
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evil_ash_xero
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Re: Good place to get shielded RGB cables now?
The SNES and SNES mini have horrible interference, unless you use official cables, or really well shielded cables.bobrocks95 wrote:What kind of interference?evil_ash_xero wrote:Interesting. Can their SNES cables actually get rid of that interference? I get that, even with the official cables. I still get interference (not very noticeable now) on the SNES Mini (RGB modded).
I wonder if that would fix that? That's like the worst offender, when it comes to interference.
Buzzing, rolling waves on your screen...the whole shebang. In my experience, the mini is actually worse than the first one.
My Collection: http://www.rfgeneration.com/cgi-bin/col ... Collection
Re: Good place to get shielded RGB cables now?
My Snes Mini doesn't have any of those problems. I'm using a Retro Access cable but the system was also heavily modded. Voultars RGB board, c11 replaced. new voltage regulator, recapped power supply, and a digital audio mod.evil_ash_xero wrote:The SNES and SNES mini have horrible interference, unless you use official cables, or really well shielded cables.bobrocks95 wrote:What kind of interference?evil_ash_xero wrote:Interesting. Can their SNES cables actually get rid of that interference? I get that, even with the official cables. I still get interference (not very noticeable now) on the SNES Mini (RGB modded).
I wonder if that would fix that? That's like the worst offender, when it comes to interference.
Buzzing, rolling waves on your screen...the whole shebang. In my experience, the mini is actually worse than the first one.
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Re: Good place to get shielded RGB cables now?
I also have never had any of those problems with either an unmodded fat SNES or my mini with Voultar's board in it. Heck I'm not even using the nice Retro Access cable, I'm just using the cheap cable they don't even sell anymore. My NES had audio buzz until I upgraded, but I've otherwise had very good results with Nintendo systems.
Re: Good place to get shielded RGB cables now?
I am in the middle of an adventure in making my own cables for an Extron Crosspoint connecting twelve consoles and six monitors, and I've done some research relevant to this thread.
My brilliant idea was to get a 50m VGA cable on clearance, cut it up into 20 lengths of 2.5 meters each, and cannibalize my crappy old 3rd party SCART cables for console connectors. Components like resistors, capacitors, and sync strippers will be contained in small breakout-boxes, and BNC connectors will be provided cheaply by these. I'll take pictures when everything is done.
The cable has proper 75-ohm coax lines for the RGB signals, which is nice, but it's perhaps not as relevant for 240p gamers as that Retro Access article makes it seem. Any individually shielded wires would likely do the job just as well.
The argument in favor of 75-ohm coax is that it prevents signal reflections. This image illustrates how reflections happen when a wave changes the medium it's travelling through. For video transmissions, this occurs whether you change the type of cable halfway through the line or simply use the wrong type of cable altogether.
Yet this phenomenon in general only occurs when the length of the mismatched medium exceeds 1/4 of the signal's wavelength.
Most 320x240p systems have dot-clocks around 7MHz. 512-pixel-wide modes are usually around 10MHz, and the Saturn's 702-pixel-wide resolution uses a 14.2MHz dot-clock, just FYI. At the speed of light in a vacuum, a 7MHz signal has a wavelength of about 42.3 meters. One quarter of that is about 10.5 meters, and a general guideline is to halve that value again since electrical signals don't actually travel at light speed.
Therefore, as long as you're only playing low-res games, the phenomenon of reflection because of impedance mismatching shouldn't happen at all until the length of your mismatched cable exceeds five meters. Furthermore, the amount of reflecting starts small and grows incrementally as your cable gets longer, and it might not actually become visible until the cable is longer than anyone would ever use in a typical game-room setup.
There is a caveat, however: fast rises and falls in a signal (imagine a black pixel followed by a white pixel, and vice-versa) happen at an effectively much higher frequency than the overall clock. I've read that people dealing with the transmission of digital signals assume they're 20x faster. For a 7MHz dot-clock system, that would mean you would see reflecting after a mere 26cm of mismatched cable. However, I'm skeptical that such reflections would actually be perceptible, especially in CRTs displaying analog 240p natively. A setup involving digital conversion, I suppose, could be a different story.
Tl;dr - If you're only running a couple meters of cable and if you're only running low-res systems, the difference between proper 75-ohm coax and any other random shielded cable is likely negligible.
My brilliant idea was to get a 50m VGA cable on clearance, cut it up into 20 lengths of 2.5 meters each, and cannibalize my crappy old 3rd party SCART cables for console connectors. Components like resistors, capacitors, and sync strippers will be contained in small breakout-boxes, and BNC connectors will be provided cheaply by these. I'll take pictures when everything is done.
The cable has proper 75-ohm coax lines for the RGB signals, which is nice, but it's perhaps not as relevant for 240p gamers as that Retro Access article makes it seem. Any individually shielded wires would likely do the job just as well.
The argument in favor of 75-ohm coax is that it prevents signal reflections. This image illustrates how reflections happen when a wave changes the medium it's travelling through. For video transmissions, this occurs whether you change the type of cable halfway through the line or simply use the wrong type of cable altogether.
Yet this phenomenon in general only occurs when the length of the mismatched medium exceeds 1/4 of the signal's wavelength.
Most 320x240p systems have dot-clocks around 7MHz. 512-pixel-wide modes are usually around 10MHz, and the Saturn's 702-pixel-wide resolution uses a 14.2MHz dot-clock, just FYI. At the speed of light in a vacuum, a 7MHz signal has a wavelength of about 42.3 meters. One quarter of that is about 10.5 meters, and a general guideline is to halve that value again since electrical signals don't actually travel at light speed.
Therefore, as long as you're only playing low-res games, the phenomenon of reflection because of impedance mismatching shouldn't happen at all until the length of your mismatched cable exceeds five meters. Furthermore, the amount of reflecting starts small and grows incrementally as your cable gets longer, and it might not actually become visible until the cable is longer than anyone would ever use in a typical game-room setup.
There is a caveat, however: fast rises and falls in a signal (imagine a black pixel followed by a white pixel, and vice-versa) happen at an effectively much higher frequency than the overall clock. I've read that people dealing with the transmission of digital signals assume they're 20x faster. For a 7MHz dot-clock system, that would mean you would see reflecting after a mere 26cm of mismatched cable. However, I'm skeptical that such reflections would actually be perceptible, especially in CRTs displaying analog 240p natively. A setup involving digital conversion, I suppose, could be a different story.
Tl;dr - If you're only running a couple meters of cable and if you're only running low-res systems, the difference between proper 75-ohm coax and any other random shielded cable is likely negligible.
Re: Good place to get shielded RGB cables now?
Neither my SNES mini or Super Fami do that. Are you sure you aren't using a cheapo PSU?evil_ash_xero wrote:The SNES and SNES mini have horrible interference, unless you use official cables, or really well shielded cables.bobrocks95 wrote:What kind of interference?evil_ash_xero wrote:Interesting. Can their SNES cables actually get rid of that interference? I get that, even with the official cables. I still get interference (not very noticeable now) on the SNES Mini (RGB modded).
I wonder if that would fix that? That's like the worst offender, when it comes to interference.
Buzzing, rolling waves on your screen...the whole shebang. In my experience, the mini is actually worse than the first one.