Atari 5200

I was successfully able to mod an Atari 5200, 4 port, original console.  It was quite a challenge, but what I did discover is there are not many resources out there for modding the 5200.  Below is a schematic of the circuit that worked for me:

A PDF of the same document:  5200_video_out.

PDF of Rev B, with RCA and S-Video Jacks:  5200_video_out_rev_B

For the mod I did, I went with composite out, but you can just as easily do S-Video out.  This schematic is a mashup of and

This version of the 5200 video out differs in one respect, I replaced the fixed 2K Ohm resistor on the Chroma line and replaced it with a 10K, 20 turn potentiometer.  I found I was able to adjust this pot until noise was more or less eliminated from the composite video.  It may not be needed with S-Video.  Another adjustment is on the 5200 board.  There is a large potentiometer in the lower right quadrant that is the color adjust.  I loaded up Ballblazer and adjusted the colors to what I thought looked most accurate.

The connection points are as follows:

Thanks Atari Age!

A/V Port Mounted on expansion port cover.

Ballblazer. Color adjusted and you can see how clean the signal is over composite.

Composite output board, before mounting.

Closeup of A/V board.

My next project is to reverse engineer the 5200 controller to allow for the use of modern potentiometer based control sticks. And here is the pot based stick: