The Ice Tube Clock kit – An open source Russian vacuum fluorescent tube clock it!

Icetubeclock2 Lrg
This is our first clock kit design, made with a retro Russian display tube!

  • Cool glowing blue tube with 8 digits and alarm on/off dot
  • Adjustable brightness
  • Alarm with volume adjust
  • Precision watch crystal keeps time with under 20ppm (0.0002%) error (< 2 seconds a day). Pretty much every time-keeping clock in your house runs on 20ppm (or so) crystals. if you look on your computer motherboard you'll see one there.
  • Clear acrylic enclosure protects clock from you and you from clock
  • Battery backup will let the clock keep the time for up to 2 weeks without power
  • Selectable 12h or 24h display
  • Displays day and date on button press
  • 10 minute snooze
  • Integrated boost converter so it can run off of standard DC wall adapters, works in any country regardless of mains power
  • Great for desk or night table use, the clock measures 4.9″ x 2.9″ x 1.3″ (12.5cm x 7.4cm x 3.3cm)
  • Completely open source hardware and software, ready to be hacked and modded!

Complete kit comes with a 110/220V 9VDC power supply for use worldwide, all components including PCB, vacuum fluorescent tube, backup battery and a clear acrylic enclosure. Assembly is required! This kit is made of through-hole components but is best built by someone with previous soldering experience as there are many parts and steps.

For assembly instructions, user manual, code, schematics, and more, please visit the Ice Tube Clock webpage! There is also a design document describing the hardware, which is worth checking out as there are a few cool hacks involved in this design. One is an onboard open-loop boost converter that uses a microcontroller PWM pin to generate 60VDC to light the tube. Another is code for a microcontroller-only low-power RTC that runs at only 50uA without the need of an external RTC chip.

The kit is now available in the Adafruit store.

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  1. This is awesome, can’t wait to get mine…..and hack it! 🙂

  2. Once glance and my first thought was, “I must have it” – my second thought was “These will sell fast – buy it now!”

  3. Those darn calculations used for the boost converter…

    It took me 1 hour to realize that all exponential functions have been approximated away by linear current ramps.

    Basically V/R(1-exp(-R/L*t)) ~ V/L*t for small times t (inductor turn on phase). And then t was again replaced with D*T or D/f. This also gives Ipk = V*D/(f*L). And then again sneak in a factor of 1/2 to get the average current (still a linear ramp).

    If 1/(1-D) is replaced with Vout/Vin (see the wikipedia link on the clock’s ‘make’ site), you end up with Iin_avg * Vin < Iout*Vout. If it were (=), that would make sense (e.g. the average power you get out of it must be the average power you put in). Conservation of energy of some sorts.

    I’m so glad I didn’t study EE 😉

    Dirty math all over the place.

  4. robert, engineering is basically the practice where you determine when its ok to approximate/linearize and when its not. it this case, its OK 🙂

  5. yeah engineering…

    I never thought I’d like to see a more theoretical approach to a problem. I must be getting old…

    I thought I was (were?) pretty down to earth and “practical” compared to the guys from our theory/math department (theoretical solid state physics/quantum whatever), but it seems that compared to an electrical engineer I’m the one throwing too much theory at the problem 😉

    In my current job I’ve developed a tendency towards “do it properly, or don’t do it at all.”

    In this case I just didn’t like being fed with the over simplified formulas. It makes it harder to really understand I think. Start with the basic differential equations for the circuit and properly deduct/approximate.

    Anyhow, I just ordered a KIT and will be happy to do some soldering. Even if the product is based on dirty math ^.^

  6. robert, it must take you 30 minutes to calculate an LED choke resistor. the Vf is exp but its a lot easier to linearize it 😉

  7. Awww, way to introduce the coolest EFD clock I’ve ever seen AFTER my birthday. 🙁

  8. > EFD

    I mean VFT. Pfft.

  9. AHH I want one!!! I going to have to save up though.

    Question: When you say 1.0 are you going to update it? If so, what improvements are we looking at?

  10. Oooh- I want it! That is beyond cool. I’ve been wanting a clock like this for a long time- awesome product. 🙂

  11. ayush, all kits start at v1.0 – there are no plans for improvements the kit works well as is! 🙂

  12. Nice work! Put a picture of that next to ‘geek pr0n’ in the official leet dictionary.

  13. AHA! Thanks for the great idea anon, my birthday is coming up and I have been struggling for ideas… now… to hope it stays in stock long enough for the loved ones to order it for me…

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