CoCo1 composite video

Did this recently for my CoCo 2. Used a mashup of several composite mods floating around (including this one) and built it on a piece of stripboard that fit in the same footprint as the RF modulator. Sourcing the MC1372 was tricky, but NTE makes a replacement, NTE855. I used a 3.5mm TRS jack for the audio/video output so I didn’t have to drill a second hole in the case, and then all you need is a cheap 3.5mm stereo to RCA cable.

Wish I had a schematic but I kinda just wired it freehand.

Oh hey, I did this too. I'm pretty sure I tried OP's same circuit, but I wasn't happy with it.

https://alnwlsn.com/z/coco1-vid/coco1-vid.html

The 2n2222 pair is a dual emitter follower, it is unity voltage gain, but does remove some of the bias from the signal.