Rotary Un-Smartphoneâ„¢ Kit

A 4G cellphone. You know... for making CALLS.


The Rotary Un-Smartphone is a followup to this personal project. It's a production-ready ground-up design with all new parts (yes, the rotary dial too) and many neat bells and whistles.

  • Pocket-sized
  • 4G/3G/2G connectivity, obsolescence-proof for at least another decade.
  • Access and call your personal contacts faster than with a smartphone
  • Use your own SIM card with your favorite carrier's "Bring Your Own Device" option
  • Real (mechanical) ringer bell made gold or silver-coated brass; externally visible
  • Receive basic SMS messages and send pre-typed messages and numeric strings
  • 2 displays: Front-side OLED and back-side ePaper
  • Physical disconnect switch for the microphone
  • Mechanical power switch
  • MicroSD card stores contacts list as a text file
  • TRRS headset jack
  • USB-C charging port; USB Micro-B port also available
  • Incandescent-like indicator LEDs
  • Weighs 174g [6oz]
  • Injection molded parts available in several striking colors
  • Internal antenna; expansion space for user-supplied external antenna

  • Documentation:

  • Manual: An actual manual with everything you need to know in one place
  • Build Instructions: The primary assembly guide for this kit
  • Video: Coming soon
  • Pictures: Photos, renderings, and more
  • Open Source Files:

  • Firmware: Arduino-compatible
  • Electrical:The KiCad files
  • Mechanical:STEP files and PDFs
  • License: Read before forking

  • READ

    Q: Do I need to know electronics? What skills are required for assembly? Can anyone build it?

    A: This was designed to be an easy-build kit. No soldering is required, nor glue, nor cutting. One should be able to put it together in a short afternoon with a screwdriver or two, tweezers, and a careful hand.

    Q: What comes with the kit?

    A: Everything you need to make a complete, working phone. Just supply a SIM card from your cell carrier.

    Q: Will a ready-built version be available in the future?

    A: Possibly. There are bureaucratic reasons that this is not straight-forward (i.e. FCC licensing). Besides, selling a ready-to-use cellphone would warrant a level of customer support which I'm not currently able to provide.

    Q: What size SIM card does it take?

    A: The standard/full-size one.

    Q: Who designed this?

    A: All design -- electrical, mechanical, and software -- was entirely by Justine Haupt (Sky's Edge is my creative outlet).

    Q: Can I order specific parts (not the whole kit), and make the rest myself?

    A: Sure! Or, if you love doing things from scratch, you can use the design files to make the entire thing on your own. It's open source.

    Q: What's the chipset?

    A: The microcontroller is an AtMega2560 running an Arduino bootloader. The cellular module is a uBlox TOBY-L2. The specific model depend on region.

    Q: In what ways is it a more functional telephone than a smartphone?

    • Better reception because the antennas aren't packed against the electronics.
    • You don't have to navigate an operating system to get to the phone "application".
    • You can assign two buttons to be hard-coded for quick dialing your favorite people. Your spouse, parent, or child can be a single button-press away.
    • The point of the phone isn't to use the rotary dial every time you call someone, which would get tiresome fast. You can store your contacts list and then dial up your friends with just two spins of the dial. When the less frequent need to dial a new number arises, the novelty of the satisfying-to-use rotary dial is fun rather than annoying.
    • Previously, phones with physical keys required a clamshell (flip) form-factor to prevent unintended dialing. Rotary dials are naturally resistant to butt dialing.
    • Nearly instantaneous 10-segment display of signal strength or battery level. Compare to typical 4-bar signal meters.
    • The rear ePaper display (for displaying contacts) is bistatic, meaning it doesn't take any energy to display a fixed message.
    • The power switch is an actual slide switch. No holding down a stupid button to make it turn off and not being sure it really is turning off or what.
    • Physical cut-off switch for the microphone. Thank you Edward Snowden.


    $390 USD



    Update due to the global microchip shortage: Ships no earlier than September 2021 and as late as early 2022.

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