Jayzon Oeve's Berlin Uhr Nano Puts the Confusing Mengenlehreuhr on Your Desk or Wrist
Based on Dieter Binninger's record-winning design, the Berlin Uhr Nano is an unusual watch with a fascinating history behind it.
Developer-engineer Jayzon Oeve has put together a miniaturized replica of the Mengenlehreuhr, also known as the Berlin-Uhr or Berlin Clock — at the time of its launch the only public clock to tell the time via colored lights rather than the more traditional clock-face and hands arrangement.
Designed by Dieter Binninger based on a commission from the Senata of Berlin, the Mengenlehreuhr confused and delighted the public on its unveiling in June 1975. While a perfectly functional clock, it eschews any recognizable system of time-telling in favor of 24 colored lights: four red lights at the top representing blocks of five hours, another four red lights representing a single hour each, a line 11 of yellow-and-red lights for five minutes each, and four yellow lights for individual minutes.
"No one knew how to read it," Oeve notes — but despite, or perhaps because, of this confusion the engineer has opted to recreate the same design in miniature with the Berlin Uhr Nano.
Oeve's recreation is based on a PCB with surface-mount LEDs, to keep the size down. A desktop variant places the PCB at the top of a pole, as with the original Mengenlehreuhr, but cut-outs in the PCB at the top and bottom provide space for a NATO-style watch strap to turn it into a portable wristwatch.
The Berlin Uhr Nano isn't Oeve's first shot at a clock inspired by Binninger's design, having built a larger variant with a design near identical to the original dubbed the Berlin-Uhr Remastered in 2020. "Back then I used a RTC [Real-Time Clock] and it drifted quite a bit after six months," Oeve notes.
"[This time I used] a time server via NTP (Network Time Protocol). For that a Wi-Fi [SSID] and PW [Password] has to be set. Also I added two rows of indicators to show the exact second," a departure from the original design which used a single light at the top to indicate either odd or even seconds.
More details on the Belin Uhr Nano are available on Oeve's Hackaday.io project page.