The Espressif ESP32-Powered Cipherling Puts a Numbers Station Right on Your Desk
Tuning in to an SDR receiver located in the UK, the Cipherling is designed as an unusual entry into the world of spycraft numbers stations.
Designers and makers Tim Burrell-Saward and Charlie Bruce, known jointly as Mother Ultimate, are crowdfunding to produce a family of desktop toys with a difference: they're horn-shaped robots which tap into the mystery of numbers stations at the tap of a button.
"Picture this. You're an amateur radio enthusiast in the 1960s. Late one night you switch on your set and idly begin surfing the frequencies, bathing in the static whilst you search for a signal. And then you hear it," Burrell-Saward writes. "A voice. In practiced monotone it lists off an impossibly long string of numbers without error or emotion. It stops, pauses, and then repeats the string. Then a short passage of music, then silence. None of it made a single bit of sense."
What Burrell-Saward is referring to is a "numbers station," one of many mysterious and unregistered radio broadcast sources which are understood to be used by intelligence services for the surreptitious transmission of information — kept secret to all but those in the know by being mixed in with seeming-gibberish, likely through the use of a one-time pad cipher system. It's these stations that serve as the focus for Burrell-Saward and Bruce's latest art project: Cipherling.
"Cipherling connects to your Wi-Fi and listens for numbers station broadcasts (or rather, our remote receiver does)," Burrell-Saward explains of the desktop toy. "When a transmission is found, Cipherling will gently alert you through a green flashing LED and an audio ping. Press the button and you'll be patched straight into the live feed (which usually starts with a period of static before the transmission begins). The LCD screen will give you whatever information we can find about the broadcast (perhaps its location of origin or codename… or perhaps nothing at all). Press the button again and the sound stops."
The Cipherling itself is a 3D-printed device with a gramophone-style horn at the rear, curving to channel amplified audio towards the user and terminating above an LCD display. A rotary knob at the side serves as the only input, pulling double-duty as an on/off switch and volume control — with everything connected to an Espressif ESP32 microcontroller, housed in the FDM case — the final color scheme for which has yet to be decided.
"We intend to set up an SDR (software-defined radio) based receiver in the UK," Burrell-Saward says of the audio source to which the Cipherlings will connect, "which will receive and re-stream the audio via a relay server to any Cipherlings that want to tune in. We will maintain the receiver and broadcast schedule for at least five years. This means we are guaranteeing five years of functionality. After these five years, if we are unable to maintain service we will open source the following repositories: device CAD; device electronics schematics & board layouts; device firmware; SDR receiver code; server code; system-level technical documentation."
The pair are funding to finalize the design and begin manufacturing on Kickstarter under the Make 100 program, where only 100 units will be offered to backers. Those looking to pick one up will need to pledge £99 (around $123), with hardware expected to ship in July this year.