TI 99/4a to an RGB arcade monitor?

[Tornadoboy]

Just curious, is there a way to get RGB out of the 99/4a mother board that's compatible with standard arcade game monitors? If not I think I could probably just use a Dragon's Lair NTSC-RGB board but I'm not 100% sure on that either.

 

I'm probably not going to work on it anytime soon, but I've had fantasies of making a "Tex-Flex" arcade system like Exidy once did for the Atari 600 with their "Max-A-Flex" system. For those unfamiliar with it:

 

http://www.classicarcademuseum.org/game-of-the-month/Max-A-Flex.htm

Edited February 5, 2017 by Tornadoboy

[+arcadeshopper]

- the 9918a puts out composite not rgb

- you'd need a composite ntsc (with loose requirements as our TI doesn't put out super quality composite signal) to rgb like that board you mentioned which is getting rare

 

Greg

[fabrice montupet]

You also can buy an European TI-99/4A and the PHA2037 interface. Sure, the RGB picture quality is great :-)

[bpatte02]

Interesting concept. I saw a group of guys who took a raspberry pi and stepped the hdmi to VGA and then found a converter that stepped the VGA signal down to the RGB. If you had a modified TI-99/4A with VGA perhaps a step down like the GSB-8100 that these guys used might work. Or maybe a composite to VGA converter that is connected to a GSB-8100 might work. I'll be honest I'm not anywhere near being an expert, more like an avid idiot who likes to throw things at the wall and see what sticks but perhaps this article might be interesting for everyone here.

 

http://celso.io/2012/12/17/connecting-a-raspberry-pi-to-an-old-15khz-arcade-monitor.html

[Tornadoboy]

There are a number of different NTSC-RGB converters out there not just from Dragon's Lair but several gambling games that used laser discs and are cheaper/easier to find, I might try one of them, and there's also a few schematics for making one from scratch that's always an option.

Edited February 8, 2017 by Tornadoboy

[fabrice montupet]

Composite NTSC to RGB converters give poor results.

[Tornadoboy]

I do have an F18 chip, but don't you need to tweak the VGA output like the frequency in order to get it to convert it to RGB? The TI obviously doesn't have any settings for that.

Edited February 8, 2017 by Tornadoboy