This unusual device is a glass kit, manufactured during the 1960s and 1970s, that allows the user to construct a Huggins-style cathode ray deflection tube. The kit includes metal parts that can be crimped together into a deflection plate and anode assembly, filaments, a glass envelope, a glass button base, and assembly instructions.The resultant tube has two long metal plates mounted 90 degrees to each other, which can be used for electrostatic deflection. The instructions avoid the complexity of fusing the base and envelope together by having the user seal the seam with silicone sealant or JB Weld, this allows the base and envelope to be reclaimed afterwords and used to build other tubes. The imperfect vacuum allows the electron beam to be seen, which is the only 'display' this tube provides... there is no phosphor coating on the front screen of the tube. It should be said that this project is not for the feint of heart... the builder would need a 100 volt power supply and a 40 micron vacuum pump to assemble and use this tube, as well as enough common sense to not be electrocuted or poked full of holes by exploding glass.
The example shown here was actually obtained as surplus from a middle school science department. It is amusing to picture a time when public education was so metal that 13-year olds were building their own cathode ray tubes as an educational exercise.
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