Nixie-based tube clocks

by Joe Croft /

Price: $160 (kit), $399 (fully built)



Joe Croft sent in his NixieNeon clock.  What I really like about this kit is simply the number of neon bulbs and the use of less-common green neon bulbs as well.  The manual itself is worth reading through.  Clearly lots of work went in to designing this device.  (Apparently the original intent was not to use a single processor!)

The software itself is open source under the GPL license.  The core of the clock is based on an Arduino bootloader and library.

As far as the description of the operation goes, I won't try to paraphrase his description from the site:

The NixieNeon is a nixie tube clock designed with ring counters built using neon bulbs to allow the viewer to see the electronics perform the actual counting of time. This electronics kit offers the builder a glimpse back in time before semiconductors became inexpensive and plentiful. The Hour of the day is displayed using the twelve neon bulbs (the hour ring) circling the two 2 nixie tube digits which represent the minutes. The 4 green neon bulbs are for showing the positions for 12, 3, 6 and nine o'clock. They also blink to give a pendulum effect while the clock is operating.



See it in action:


by Matthew Sarnoff /

Price: not for sale


Nixie Clock

I found this clock by accident and I really wanted to feature it on this site.  There are a lot of home brew nixie clocks but most involve re-engineering every aspect of the electronics.  Matthew took a different approach.  He found an old breadboard and located matching JAN 8421 (nearly identical to a B-5092) nixie tubes.  The board had an existing edge connector to Matthew designed a clock driver to fit on the end.  Be sure to check out his site for more information about the power supply and the timing circuitry.



by Pixel Lifestyle Design

Price: est. $190 USD / eBay


Pixel Design Boulder Nixie Clock

Pixel Design just sent me a notice that they are selling a new clock design.  I originally wrote about there IN-8-2 clock in a black acrylic case a few weeks ago.  The new design is named Boulder and appears to have a newly designed chrome base that looks much more professional than their original design.  With the design improvements comes a bump in price.  The clock is currently on eBay and the current bid price (starting bid) is $198.99 USD. Is the increase in price worth it?  Probably.  This looks like a solid design.

One other thing that I really like about this device is that it is well documented.  They sent me a 16 page manual that explains how the device works, how to care for it, and provides more technical information.  You can read the full manual here.


Pixel Design Boulder Nixie Clock




by Turbo_Hobby

Price: ~ $48 USD / eBay buy-in-now

SZ-8 Nixie Clock


I just got my SZ-8 clock in the mail and I am excited to review it for you.  Shipping from Singapore took about two and a half weeks but that isn't too surprising considering that it had to clear US Import Customs.  (I originally posted about the clock here. )

For disclosure, this clock was not sent to me for review.  I discovered it on eBay by accident and purchased a unit for my own collection.  All of the photos and video in this review are mine.

{vimeo width="600" height="338"}9220187{/vimeo}

One of the stand out features of this clock is that it only has one digit.  That might be an obvious statement but it is a little unusual.  The time is displayed by displaying the digits in HHMM order.  There is a brief pause between the numbers and a longer pause once it is finished.  You can see this in the video.  To make reading easier, there are four yellow LED's which indicate which digit is being displayed.  While I have only had the clock for a short while, I already prefer having the yellow indicators on.

SZ-8 Nixie Clock

Setting the clock is a bit of a pain.  This is primarily because it didn't ship with any instructions.  When the clock first powers on, it displays every digit once, presumably as a power on self test.  Once that is done, the LEFT button turns on and off the yellow indicators.  To set the time, turn on the yellow indicators - this will make your job much easier.  The clock has already started cycling through the digits.  When it gets to a digit you want to change, hit the RIGHT button.  The clock will freeze and you can keep pressing the right button to increment the digit to the correct value.  Wait for a few seconds and the clock will resume.  Repeat this for each digit.  You do not set the hour as "12" - you set the first digit to 1 and the second digit to 2.  The clock is in 24h mode so keep that in mind when setting it after lunch.

The clock is powered via USB.  There is a mini-USB (NOT Micro) on the left side of the unit.  I really appreciate the fact that this device does not use a wall adapter.  As any gadget lover knows, there are never enough outlets around.  By using USB, you can simply plug it in to your computer or any USB wall charger if you want.  The extra flexibility that this creates is great.  For example, I have my device powered by the USB out on my Epoch Clock and it seems to work fine.  Thankfully, this device includes a battery backup - the big black circle on the back of the unit.  This should prevent you from having to reset the clock every time the power goes out.

I haven't had the clock long enough to measure drift.  I don't intend to do formal measurements of this.

SZ-8 Nixie Clock


The tube itself is somewhat unusual.  It is an SZ-8 which appears to be a clone of a Z560M tube.  The letters are surprisingly "fat" but easily readable.  The tubes are not new but they do not show any obvious signs of use.  There is no evidence of cathode poisoning and don't appear to be any defects in the tube.  Additionally, the seller included a spare tube in case the original one breaks/dies/etc.  I do unsure if these tubes contain mercury.  They don't have the typical blue/violet glow like an IN-18 does so I am inclined to say they they do not.  (Mercury helps prolong the lifespan of the tube.)

SZ-8 Nixie Clock

The clock is smaller than an average smart phone. It is about four inches tall by two inches wide.  It is about an inch and a half deep, largely because of the tube.  There are four standoffs that are included which would help with mounting if you want to build a custom frame.  It does not, however, come with an enclosure.  This is my single biggest complaint about the device.  You probably won't be harmed if you touch the power supply but you might feed a bit of a shock.  I haven't tried so I can't say for sure, but 180v would probably be noticeable.  There is very little current so I highly doubt it would be anything more than a tingle.  The other problem that the lack of a case produces is that the clock doesn't want to stand vertically on its own.  It is top heavy because of the tube and the USB cord on the left means that it is constantly falling over. I have mine wedged on my desk to prevent it from falling, but an enclosure or sturdy base would solve this.

Overall I really like this device. When he produces more, go buy one.  At this price, you can't go wrong.  All of my complaints are minor and I doubt you could even build one of these clocks for cheaper.  I had a positive experience buying from Turbo_Hobby and would not hesitate to buy from him again.

UPDATE: 6-16-2010:

He now includes an acrylic enclosure with the clock.  This seems to resolve all of the stability problems I encountered.  Go buy it now!

Verdict: Buy It


  • USB Powered
  • Clean PCB layout
  • Battery Backup
  • Inexpensive
  • Well built
  • Unusual display


  • Top heavy design means it falls over frequently


Go to top
JSN Boot template designed by