Nixie tubes are really cool looking and are becoming quite popular for their 'retro' look. Although there are a number of tutorials out there on using nixie tubes and some nice pre-packaged units (see these nice ones from ogi lumen
) I hadn't seen a simple tutorial on running them using a shift register like the SN74HC595. This would use the minimum number of Arduino pins as it can run as a serial device. Another nice addition is the use of the SN74141 BCD to decimal decoder/driver chip. This chip allows direct control of the Nixie tubes from the shift registers without the use of individual transistors for each numeral. An added benefit to using shift registers is that additional pairs of Nixie tubes can be added without using any more Arduino output pins. They just get daisy chained to the first set. WARNING: Nixie tubes require a high voltage power supply, typically 150-180 volts. This is enough voltage to hurt you. Please make sure you know what you are doing.
Note: please let me know of any typos/errors/comments so I can continue to improve this Instructable.
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