2513 Character Generator

This description of the 2513 Character Generator is from Don Lancaster's TV Typewriter Cookbook. The description explains clearly how this thing works. Compared to the datasheet, I thought this was easier to understand, so figured I'd share it with the community.

I've been spending a bit more time on the video section of my Apple 1 clone, trying to locate the source of the problem (I have a signal, but no video). I re-soldered most of the points on the back of the board thinking maybe I had either a solder bridge or just a bad connection. I pulled and reinstalled the chips. Still no video. I tried removing and reinstalling all RAM chips, still no video. I tried swapping out a few of the chips, still no video. I checked all of the 1404 voltages, and everything looked fine. I'm going to have to spend a little more time with the scope, the schematics and the datasheets to figure out what's wrong here....