...about 30 years ago. There should be a little RCA emblem above the pilot lamp. I still have the emblem mine came with. I honestly don't remember what happened to the machine. I probably traded it to someone for some other super-cool toy. I used to do that a lot. Occasionally I think about it and wish I had it back.
It is a modulator, and if I remember correctly it did B&W only, no color
It was crystal controlled for each channel. PL259s for everything on the back. I can't say it was the exact same model as that one, but it sure looked a lot like it. I may have a snapshot of mine somewhere. I guess I'll need to dig for it.