Well, it appears to be transversely excited. It's definitely a water cooled, sealed tube CO2 of some sort. It has three input "buttons" at the bottom that kinda look like old florescent lamp igniters. I'm guessing each one goes to a separate electrode bar. Gotta throw a meter across them.
Anyone seen one of these before? the tube has no markings except for "10 6" which could be a serial number or wavelength. It does appear to be gas intact with a little HV test.
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