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Topic: Arduino driven Nixie Clock (Read 10202 times) previous topic - next topic


Feb 24, 2009, 06:58 pm Last Edit: Feb 24, 2009, 06:59 pm by Skizzo Reason: 1
At the beginning of 2009, I stumbled across some Nixie vacuum display tubes online, and promptly purchased them. I also happened to have a 3.3V Arduino Pro from Sparkfun laying around doing nothing, and apparently too much time on my hands. So, it was the perfect recipe for a Nixie Clock driven by an Arduino.

The clock uses six IN-8 Nixie tubes, six 74141 BCD decoder IC's to drive the Nixies, three 74HC595 serial to parallel shift registers, a DS1305 real-time clock IC to keep time, and a quadrature rotary encoder with integrated push button to set the time and other functions.

I have a lot of cleanup to do on the code, but it works as of right now. I also plan on implementing more features, but I thought that I would share my results so far.

I need to get some better pictures of the Arduino in the mixture, but it's in there :-)

The Arduino reads and sets time from the DS1305 RTC via SPI. The DS1305 also has a few bytes of user-usable memory, so I use that to store other information about user-settable functions. Right now, the one function I have is to be able to put the display to sleep so that the Nixie tubes last longer. I can set the hour in which they sleep and the hour where they wake back up using the rotary encoder. The integrated pushbutton lets me commit my changes and change the mode. Right now, mode 1 displays the time, mode 2 lets me set the time and modes 3 and for set the sleep and wake times for the display. I'm going to implement more functionality, like whether or not to display the time in 12/24 hour mode, and a cathode-poisoning defense mode that will light all the digits on all the Nixies periodically. I will probably also add a date display feature, since the hardware already has this capability.

The Arduino also controls the 595 shift-registers using ShiftOut(), in which I output binary coded decimal (bcd). While developing this project, before getting the high-voltage power supply and 74141 drivers for the Nixies, I used the 595 shift registers to turn LED's on and off. Essentially, I made a binary clock, and then turned that into a Nixie clock by replacing the LEDs with Nixie drivers. It actually worked out better than I thought it would :-)

I am actually considering coming up with a PCB design that will house the RTC, Shift registers and 74141 drivers so that I can make my next clock even better. For now, though, this hacked up attempt is encouraging to me. It's my most complicated electronics project to date.


Awesome! I love nixies. Some day I'll have some of my own, and I'd love to build my own clock like this.


Feb 24, 2009, 09:32 pm Last Edit: Feb 24, 2009, 09:33 pm by koyaanisqatsi Reason: 1
Ha!  Retro-cool!   8-)

Yup, I'm adding this to my (large and growing) list of Arduino projects too.

EDIT: BTW, how much do nixies cost these days?


Thanks guys :)

The IN-8 Nixies weren't actually that expensive - they were around $4 each, I think. They are relatively small - the digits on them are 18mm tall. You get a little nickel and dimed, though, with all the other components necessary to drive and power them. And, many of the components can only be found from Eastern European counties, so they have to be shipped.

The 74141 drivers can be found for under $2 if you're buying them in quantity, but for only a few of them, I was having a hard time finding then for under $3.50 each. Those are also manageable. The cost on the components for my power supply was somewhere between $16-$18 though; by far my largest single expense next to the Arduino itself. All said and done, including the cost of the Arduino, I spent around $100 for all the components of the clock. I'm sure I could have made a cheaper clock using a RBBB, and even less expensive (overall) Nixies (The IN-8's require pins - they're designed to be used in a socket. IN-8-2's do not require sockets - they solder directly to a PCB.) But "build the cheapest clock I could" was not the requirement of this project. ;)

The next part of the project is to build a case for it. Not being one for woodworking, it's crazy that I've decided to house the guts of this in a Redwood burl case. That will be an interesting part of the project. I will make sure to post pictures once it's done.


Good stuff!  I have some Nixies that I bought at Mendelson's surplus store in Dayton, Ohio, but have yet to wire up.


Yeah! Such digits lamps released in the Soviet Union.))

What would you say about this really geek device?))


foxweb, There are lots of interesting things on that site: http://www.electricstuff.co.uk


where would one buy a nixie wrist watch like that? i must have one! it will make me look super cool  8-) or like a complete nerd (more so than i already look  ;) )


As far as the Nixie watches go, I like the one from Cathode Corner better than the one foxweb posted. That one is neat, but the CC watch is much more usable on a daily basis - it looks more like an adult watch.

Ahh, maybe someday... Until then, I have my Arduino clock to play with.


lovely work
i plan on doing some similar as well as a few other nixie duino projects

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