Nixie Clock II
A four-digit Nixie clock created using a display board from an unknown piece of 1970s equipment. (The logo in the corner looks like it says "TTI"; can anyone identify this?)

An adapter board is used to bring the card edge connectors out to a row of 0.1" spaced pins.

A perfboard behind the main display board contains an AVR-based clock circuit, which is connected to the pins of the adapter board.

The clock can be programmed to turn on and off at various times, to preserve the tubes. Since it's in my office, it's programmed to turn on when I come in, turn off when I leave, and not turn on at all on weekends.
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