What exactly is preventing my AV Famicom to use the S-Video out of my SuperFamicom?

[the.importer]

Since they use the same output plug, I've tried swapping the Famicom one for the SuperFamicom and got no sound or picture. Is there any modification that can be done to get S-Video working on that system?

[Joe Redifer]

Because the NES video encoder doesn't output direct RGB to be made into S-video somewhere, it only does composite. I agree, it should work, but those crafty engineers at Nintendo had different plans.

[the.importer]

Because the NES video encoder doesn't output direct RGB to be made into S-video somewhere, it only does composite. I agree, it should work, but those crafty engineers at Nintendo had different plans.

Don't suppose that someone could be more "crafty" than Nintendo and mod this thing?

[JFLY]

One thing that continues to baffles me is why does my NES output a cleaner composite signal than my AV Famicom?

[Joe Redifer]

Nintendo is more crafty than the modders. The only way around it is to install a PPU from a PlayChoice arcade machine. The easiest way is to just buy a Famicom Titler unit (which itself is a Famicom that outputs RGB).

[kool kitty89]

One thing that continues to baffles me is why does my NES output a cleaner composite signal than my AV Famicom?

Same reason the NES2 has poorer video (even f modded with composite), poor sheilding internally, resulting in noisy video. Note the box of metal sheting sheilding the audio/video components around the ports inside the toaster NES.


Importer, the NES PPU was designed to output composite video natively, its palette also caters to that (as with previous ones like the TM9918 in the colecovision or Atari's TIA -not sure if tia offers separate chroma and luma connections though, CTIA/GTIA did; plus another version of the TM9918 output YPbPr component video natively, to facilitate transcoding into other formats externally)

The NES PPU doesn't output RGB, YUV/YPbPr, or separate luma and chroma signals needed for S-video. I think it wirks with a YUV palette internally, rather than RGB, so liek the TM9918, that would have been a more natural alternative. The obvious reason for switching to RGB would be due to arcade monitors using it.


Now, one of those crappy Nintindo multi AV "s-video" cables will output video from the AV famicom on s-video, but those suck and just put composite on Y/C pins of s-video. (resulting in awful artifacts and much worse quality than straight composite)

However, you might be able to het a high quality comb filter that can split the composite signal to luma/chroma for s-video. (some high-end laserdisc players did this -as LDs used composite natively) But if you did that, it'd be most usefulas a universal comp=>s-video adaptor rather than installed w/in a console. (of course, some TVs have really nice comb filters internaly, but that's hardly consistent, and mainly on some older, high-end SD CRT sets -I've seen an old Zenith AS3 that made a genesis via RF look almost as good as S-video screenshots I've seen -not only a great comb filter, but amazing variable automatic fine tuning which completely removed the awful RF noise from my pre-tmss model 1)

[Lastcallhall]

Sorry to necrobump this, but I saw this:

http://www.svideo.com/svc2ypbpr.html

And wondered if anyone actually went through w/ KK's idea of getting a comb filter/transcoder to test on the NES? Also - this thing is expensive! Anyone know what it would take to make one?

[Guntz]

Now, one of those crappy Nintindo multi AV "s-video" cables will output video from the AV famicom on s-video, but those suck and just put composite on Y/C pins of s-video. (resulting in awful artifacts and much worse quality than straight composite)

To be more specific, there are two kinds of Nintendo Multi-AV S-Video cables. Ones that you just described and true S-Video cables with separate Y and C. Bad S-Video cables are commonly found in the form of combo cables that have both composite and S-Video and sometimes support the PS2 and Xbox as well. Avoid those kinds of cables at all costs! Usually, dedicated Nintendo S-Video cables do use true S-Video, ones without a composite plug.

[Ace]

Bad S-Video cables are commonly found in the form of combo cables that have both composite and S-Video and sometimes support the PS2 and Xbox as well. Avoid those kinds of cables at all costs! Usually, dedicated Nintendo S-Video cables do use true S-Video, ones without a composite plug.

Is it uncommon to have one such cable which actually has true S-Video as well as Composite? I have a MadCatz dual Composite/S-Video cable like that and I checked the S-Video plug with a multimeter and concluded the S-Video is real S-Video as the Composite video is not passed into the Luminance pin on the S-Video plug(and my Super Famicom Jr. does not display anything when using S-Video with this cable).

[Guntz]

Yes, it is uncommon. I've gone through a decent number of combo cables that all had bad S-Video. For everyone else reading this thread, dedicated S-Video cables are more likely to be authentic.

[Ace]

I did get screwed over by one such cable for my Dreamcast as I needed to get a cable of that sort so I can both play my Dreamcast games on my TV and record video from it at the same time. When I found out the cable simply took the Composite from the multi-A/V out and sent it into the Luminance pin of the S-Video plug, I stole the plug from the cable and built a VGA box for the Dreamcast with true S-Video output for when games don't work in VGA. The rest was trashed(better that way).