View Full Version : UK TI99/4A trying and failing to do a composite mod

December 30th, 2015, 10:42 AM
I am now trying to do this composite mod for my TI99/4A:


I have followed the directions and tested and insulated all my connections but on two T.V.'s (both lcd) I get a barley visible grey screen that is like a poorly tuned in aerial signal.If I use the aerial connection it's appearing correct (albeit fuzzy like normal).
Anyone else done this mod? (It's different from the American version as European TI's have a 6 pin video output).

December 30th, 2015, 11:35 AM
The American TI-99/4A already has composite video available on pin 4 of the DIN plug video output. It uses the same pinout as an Atari 800.

The European version outputs YUV (component) video, as discussed here:


December 30th, 2015, 11:49 PM
YUP read all of that whilst searching for a way to get composite from my UK TI.
Most of those threads are over 5 years old now and I don't know if those forums are active.
I was just wondering if someone else here has had a similar problem and might know the solution as the page I posted has a modification for the Euro TI to output composite from the modulator box.

December 31st, 2015, 05:34 AM
Fabrice Montupet is still very active within the TI community, so you might try to check with him. You might also check on the Italian TI Users' Group (http://www.ti99iuc.it/menu.html) site. They also have a forum (somewhat low activity, but still live), and the guy who designed the mod in the first place may still be there. You might also try to talk with Stuart Conner (http://www.avjd51.dsl.pipex.com/) about it. He's also here, so he may chime in soon in any event.

January 1st, 2016, 06:50 AM
Thanks for the link to the Italian site.After running it through google translate I found out it's still hit & miss if this mod works with modern LCD's.Tried it on my old crt monitor after digging it out of storage and it out outputs fine.
At least now I know I'm not doing anything wrong.