A more complete list of X-Y (also called vector) video game machines, from the Golden Age of Coin-Op Arcade Games:

There are others, I'm sure, that I've missed. /msg me or add 'em on! I own several of these machines, and cranky though they are, they just rule to have in your house...wandering to the bathroom at night, dark sinister voices will taunt you from the kitchen, daring you to slot a quarter and eat hot death.

A final note on X-Y monitors; the main manufacturers of the monitors used in these games were Electrohome and Wells-Gardner. Due to the high, fluctuating voltages required to make the electron beams in these monitors perform their required gyrations, the monitors have a tendency to blow out flyback transformers and the large capacitors used in the vector unit. Happily for all of us who own them, a gent named Anthony Zanen, of Zanen Electronics, makes a series of get-well kits for these monitors (customized to each monitor model) which contain modern, higher-rated parts to replace the 'problem' parts used originally to save money or that were lower-tech. Reports indicate that monitors so upgraded become nearly problem-free.