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Plastik

S-Video Possible?

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It's been a while since I've been on here. :skull: But after a busy hiatus I'm back to messing with the Ti again. I'll be modding my C64 and Vic 20 for S-video soon and I'd like it to share the same screen with the Ti. I've looked everywhere but could come up with anything. I know there is the F18a but I'd like it to be S-video like my other Comps. Can anyone chime in with a little info on where I can tap for Chromo and Luma? I was able to find this schematic but it looks to be in German. This of course being for the 6 pin Euro video out that does composite..lucky..I'm not bitter I promise........maybe just a little..

 

Thanks

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It's been a while since I've been on here. :skull: But after a busy hiatus I'm back to messing with the Ti again. I'll be modding my C64 and Vic 20 for S-video soon and I'd like it to share the same screen with the Ti. I've looked everywhere but could come up with anything. I know there is the F18a but I'd like it to be S-video like my other Comps. Can anyone chime in with a little info on where I can tap for Chromo and Luma? I was able to find this schematic but it looks to be in German. This of course being for the 6 pin Euro video out that does composite..lucky..I'm not bitter I promise........maybe just a little..

 

Thanks

 

How about this RF Modulator for a TV monitor? It has 75-Ω I/O, S-Video input and A/V stereo inputs (RCA jacks). You might find one really cheap if you have a Radio Shack going out of business near you—I did. They are also on ebay for less than half retail.

 

...lee

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There are a few okay SVGA to S-Video/Composite adapters out there, but it kind-of defeats the purpose of the F18A and down-scaling VGA to NTSC almost always leaves a good bit to be desired. From a native console perspective, I found good composite-to-S-Video adapters on a Yahoo store a while back. The signal winds up being a little dotted, but no crawlers like some of the others I have tried, so IMHO it is a good adapter.

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Native S-Video is the sharpest compared to composite, using an adapter would defeat the whole purpose. I just don't want to shell out for a F18A right now as I'd rather use that on a NanoPEB. I'm surprised it seems no one has brought this up before. Guess everyone just went the VGA route with a F18A.

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There was an adapter called the Video Turtle that converted a TI RGB signal to Svideo. I helped demo it at one of the Lima Faires and it did a pretty good job on a large CRT TV. There's been some recent interest in that device recently, and maybe another run is possible. I'd like to see what it looks like with a flatscreen monitor.

 

Gazoo

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The 9918A video chip only outputs composite, and that is as good as You are going to get from a standard TI. Myself and others have tried

to get a working component video output from either a 9928A or 9929A (PAL) chip with minor circuit modifications, but generally it doesn't work.

I think it has something to do with the fact that the TI outputs 480p not 480i, and most tv's don't understand the input.

 

To get S-video you would have to build or buy a converter that splits the composite into luma/chroma, cleans the signal, then outputs that as

s-video. I doubt that would result in a satisfactory quality.

 

IMHO You are better to just bite the bullet and get an F18A, or just put up with the composite until You can afford one.

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Native S-Video is the sharpest compared to composite, using an adapter would defeat the whole purpose. I just don't want to shell out for a F18A right now as I'd rather use that on a NanoPEB. I'm surprised it seems no one has brought this up before. Guess everyone just went the VGA route with a F18A.

 

http://atariage.com/forums/topic/172937-getting-s-video-from-the-ti-console/?p=2144101

 

And others before me. Bottom line in my experiment, the video from the 9928 is the wrong color space.

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There was an adapter called the Video Turtle that converted a TI RGB signal to Svideo. I helped demo it at one of the Lima Faires and it did a pretty good job on a large CRT TV. There's been some recent interest in that device recently, and maybe another run is possible. I'd like to see what it looks like with a flatscreen monitor.

 

Gazoo

 

Hey Gazoo is there any documentation on this turtle converter? Sounds interesting.

 

The 9918A video chip only outputs composite, and that is as good as You are going to get from a standard TI. Myself and others have tried

to get a working component video output from either a 9928A or 9929A (PAL) chip with minor circuit modifications, but generally it doesn't work.

I think it has something to do with the fact that the TI outputs 480p not 480i, and most tv's don't understand the input.

 

To get S-video you would have to build or buy a converter that splits the composite into luma/chroma, cleans the signal, then outputs that as

s-video. I doubt that would result in a satisfactory quality.

 

IMHO You are better to just bite the bullet and get an F18A, or just put up with the composite until You can afford one.

 

It's seem so strange to me that the PAL Ti gets RBG but we got shafted in NA. There has to be some way kinda like with the Amiga 500 where you use a AD724 and crystal clock to turn the RGB to S-Video.

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http://atariage.com/forums/topic/172937-getting-s-video-from-the-ti-console/?p=2144101

 

And others before me. Bottom line in my experiment, the video from the 9928 is the wrong color space.

 

OLD CS1 did you try to pump up the (Luma) with a 2n3904 transistor and +5v? I didn't read the whole thread but from the first picture it just looks like a weak (Luma) signal.

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The 9929A and 9928A ouput Component, which is not the same as RGB unfortunately.

 

I have one of those GBS8220 converters that I was going to have a go at after I mod a PAL or NTSC 9928/9929 chip into one of my spare TI's.

They are very cheap from China, I have attached the PDF for anyone interested.

 

I tried it with my Amiga 500, but the result was no better than the S-video modded A520 modulator. BTW that has the best quality s-video output of any

of my computers, so it would have to be near perfect to better it.

GBS-8220_CGA_to_VGA_HD-Converter.pdf

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The 9918A video chip only outputs composite, and that is as good as You are going to get from a standard TI. Myself and others have tried

to get a working component video output from either a 9928A or 9929A (PAL) chip with minor circuit modifications, but generally it doesn't work.

I think it has something to do with the fact that the TI outputs 480p not 480i, and most tv's don't understand the input.

 

To get S-video you would have to build or buy a converter that splits the composite into luma/chroma, cleans the signal, then outputs that as

s-video. I doubt that would result in a satisfactory quality.

 

IMHO You are better to just bite the bullet and get an F18A, or just put up with the composite until You can afford one.

 

Correct, you would need to update the 9918,9928,9929 to a 9938 or 9958 to get RGB, which you would then feed to your RGB to Svideo converter (Video Turtle).

 

If you're switching Svideo inputs, that's the way to go.

 

Gazoo

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OLD CS1 did you try to pump up the (Luma) with a 2n3904 transistor and +5v? I didn't read the whole thread but from the first picture it just looks like a weak (Luma) signal.

 

Nope. Gave up:

 

I did some digging around and found that what I am doing may not work, anyway. The NTSC S-Video standard is Y/C, luma and chroma. The B-Y and R-Y outputs are the U and V parts of a YUV signal, however, NTSC S-Video is not *really* YUV, but is a slightly different color space, YIQ.

 

SGI has a good page which goes over the differences, here

 

Appendix A. Video Basics

http://techpubs.sgi.com/library/dynaweb_docs/0530/SGI_Developer/books/Ind2Vid_PG/sgi_html/apa.html

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Nope. Gave up:

 

 

Yeah I guess it is futile, which is a shame things like that really bug me. Well I guess with the option of the F18a, its just the way to go.

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