Nixie tubes
Donor: David Coahran
Nixie tubes are vacuum-sealed tubes that contain a wire mesh anode and a series of cathodes in the shape of members of a set of characters, typically arabic numerals. They are an example of code-cathode tubes, filled with a mixture of gases usually containing neon at a low pressure. Applying around 170V DC between a cathode and the anode will cause the cathode to emit a glow, creating the effect of displaying the corresponding character. They were introduced in 1954 by Burroughs Corporation, and used in clocks, frequency counters, early computers, and other electronic equipment. Manufacturing of nixies petered out by the early 1990s, but since the late 1990s there has been a nixie revival of sorts among electronics enthusiasts, largely because of their unique aesthetic.
8 total. It appears that several of these aren't actually nixie tubes, since they don't have any character-shaped cathodes, although the pin count, shape, and size of these mystery tubes are the same. They also have 9 pins, which Prof. Stone described as a "mystery" in his notes.
References: http://en.wikipedia.org/wiki/Nixie_tube
