It's funny that you don't really get an impression of what this is all about on the front page. I don't know what a Vectrex is, and I'm confused. Something with games I guess.
Yeah, Vectrex was a vector gaming platform (as opposed to bitmap) that came and went in the 80's. Vector arcade games were a kind of niche anyway — like "Asteroids", "Battlezone", "Tempest" and a Star Wars game. But they were also kind of magical. The Vectrex captured that.
First game I saw with merely lean based controls was hang on or space harrier, several years later.
I'm going to go out on a limb and say you found a highly custom cabinet, and I'm jealous.
That crazy glow was just so sci-fi for us kids back then. Some of us only had Game & Watch (LCD cells) to play with - the rich kids with their Vectrex were constant subjects of envy among us nerd kids.
I was lucky enough to get a microcomputer for one of my teenage birthdays - my rich neighbor had a Vectrex. We both kind of tired of our respective systems and on occasion would swap for the weekend .. it was great to have some actual games to play, and my friend enjoyed learning to program on my Oric-1 (which had a distinct lack of titles, at least in my neck of the woods back then ..)
Basically the only new principle involved is that instead of cathode ray beams always scanning on a fixed rectangular pattern, the X and Y deflection amounts were provided by the game to move around the singular dot to desired locations.
It's crisp as waving around a laser pointer. Some people like that aesthetics.