Here is the correct PinOut of the 6-Pin-Videoport: (Euro video connector)
1 +12V
2 Y
3 R-Y
4 B-Y
5 Audio
6 Mass
You can get a Monochrome Signal with 2 and 6
For a Colour Signal you need the TV-Modulator.
I just dont understand.. somehow that tv-modulator has to have color signal. Could this be connected to Chroma/Luminance S-Video connector+audio somehow..
Hm, is "Mass" the same thing as ground, located in the shell? From what I know, the TI-99 uses a 5-pin DIN like the VIC-20 but usually with component video (Y:R-Y:B-Y) . I think there was a later version of the 99 (perhaps only NTSC version) that uses a somewhat VIC/Atari compatible pinout, i.e. not the one you posted.
The component video works like this:
Y carries luminance
R-Y is the first colour difference signal
B-Y is the second colour difference signal
It is important to realize that component video output and RGB video output are not the same and are not directly compatible with each other, however, they are easily converted either way using a transcoder.
You can buy a such transcoder, but they seem quite expensive, at leat $100 and upwards. There doesn't seem to exist a simple circuit, much due to you need to generate a subcarrier for the colour signal when you convert R-Y + B-Y into S-Video. Of course, if you have a TV or other input device that takes component video (typically three jacks), you could probably make an adapter and use the TI video straight away.
Perhaps the computer itself is faulty? Did you get an acceptable monochrome picture using a different cable? The signals Y, R-Y and B-Y were not mixed around in the cable or when connected to the TV?
carlsson wrote:Perhaps the computer itself is faulty? Did you get an acceptable monochrome picture using a different cable? The signals Y, R-Y and B-Y were not mixed around in the cable or when connected to the TV?
I got picture with tv-modulator. But tv-modulator pic is what it is. And it has snow/rain. So computer should be ok.
Signals should not be mixed. I did order cable from Sta.
I was thinking.. Maybe my monitor doesnt support resolution that TI-99 does output.. Pic of monitor diagnostic screen says 720x576i.
Hm.. so there are at least three pinouts depending on region and vintage:
1. 5-pin component video (NTSC, most/early models?)
2. 6-pin component video (PAL, all models?)
3. 5-pin composite video "American standard" (NTSC, late models?)
What are the odds that Joe mirrored the signals, so instead of sound you have +12V and the signals Y and B-Y swapped? I think it should be rather simple to measure whether you get +12V out from the sound output or not, and that error could be eliminated. In the mean time, I don't think you'll damage anything if you swap Y and B-Y connectors and try again?
Also tryed old Commodore 1084S monitor with CVBS, gives nice B/W picture. But no colors. Green(Y) gives picture, but pic stays B/W, I tryed plug in those other two blue and red connectors with Y. With blue B/W picture looks better.
No, the 1084 does not have component video input in any form. Judging from the link I posted earlier, there is no simple conversion from component to composite video; rather several different complex circuits depending on what conversion quality you want to get.
It is possible that the component video signal the TI outputs is not pure in the sense a modern TV that accepts component video can handle it. If that is the case, that would be 80 Euro quite wasted. If you have a local TV dealer who sells that type of box, ask them if you can bring equipment to test it before buying. Or for that matter, try a few different TV sets, if they dare to let you plug anything foreign into the TVs on display.
Maybe you want to become a member of the 99er.net forums, which beside the corresponding Usenet newsgroup should be the most competent community on the TI-99. Good luck.
Perhaps you have some friend who is a whizz in electronics (or someone on this forum if nothing else) and you could exchange services. I would investigate if the video output is supposed to be used as component video out of the box or if you need to adopt it - perhaps adding resistors if the voltage is higher than the spec requires - before building or buying an extra box.
By the way, you wrote that you have a RF modulator, but the picture displayed is snowy? It is a picture with colours? Here is the same French guy as referred to before, modifying a RF modulator so it outputs composite video + audio. It doesn't look quite like rocket science, but requires some soldering skills. http://perso.orange.fr/fabrice.montupet/ti99r1.htm
Mikam73 wrote:By the way, you wrote that you have a RF modulator, but the picture displayed is snowy? It is a picture with colours? Here is the same French guy as referred to before, modifying a RF modulator so it outputs composite video + audio. It doesn't look quite like rocket science, but requires some soldering skills. http://perso.orange.fr/fabrice.montupet/ti99r1.htm
Yes. I just tryed tv-modulator a moment ago. Picture could be better, more sharp etc. Picture had less errors(snow) when I did hold cable connector that comes from tv-modulator at hand same time I used computer. It looks like that metallic connector/adapter I have gives errors to picture and when I keep it had it got ground, so it did help.
I also readed that RF mod could be converted output composite video/audio. It might be good idea, if I find someone who could modify it.
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I did check link, it doesnt look difficult thing to do. Thanks.
If it was me, the trickiest part would be to fasten the RCA connectors into the box, although I would probably look to get a fresh set of tips for my soldering iron before getting into it.
Based on discussions on the 99er forum, the 5-pin component video pinout most recently found when searching on Internet, is seldom or never heard of in real life. Maybe all those people have /4A models, if that is the one which outputs composite video by itself. It would also suggest the RF modulator used for a /4 model is not compatible with the RF modulator used for a /4A, despite the same pinout. Somewhere I read that a TI-99/4A RF modulator almost can be made to work with a VIC, if one uses an external +12V power source as the VIC only outputs 5-6V in its video connector. On the other hand, the number of TI modulators probably is so low that it'd better to find a generic RF modulator and make your own cable than to hack an existing one in case you desperately need a VIC-20 RF modulator.. but we all known a composite video connection is sharper.
carlsson wrote:If it was me, the trickiest part would be to fasten the RCA connectors into the box, although I would probably look to get a fresh set of tips for my soldering iron before getting into it.
I would just solder in cables and add supports ("dragavlastning") inside the modulator. No need to have the contacts fitted inside the shell of the modulator.
carlsson wrote:Based on discussions on the 99er forum, the 5-pin component video pinout most recently found when searching on Internet, is seldom or never heard of in real life. Maybe all those people have /4A models, if that is the one which outputs composite video by itself.
I think the TMS9918A video chip outputs component natively, whereas the TMS9918 outputs only composite, so I'd wager that the original 99/4 model is the one with composite on the video connector.
carlsson wrote:Somewhere I read that a TI-99/4A RF modulator almost can be made to work with a VIC, if one uses an external +12V power source as the VIC only outputs 5-6V in its video connector. On the other hand, the number of TI modulators probably is so low that it'd better to find a generic RF modulator and make your own cable than to hack an existing one in case you desperately need a VIC-20 RF modulator.. but we all known a composite video connection is sharper.
I don't think anyone desperately needs a VIC-20 RF modulator, considering that it's so easy to get composite from the VIC.
