Jouke Waleson's Mid-Century Bakelite Telephone Has Very Modern Bluetooth-Capable Innards

Maker, developer, and "fractional CTO" Jouke Waleson has a mid-century Bakelite desk phone with a difference: it's a fully-functional Bluetooth handset for a modern mobile phone or computer, thanks to new innards that include an Espressif ESP32 microcontroller.

"It's a Dutch PTT phone model called simply '1950'," Waleson explains of the attractive black Bakelite rotary phone, named for the year of its release by manufacturer Standard Electric. "But, what's this at the back? A USB-C port? A peek inside shows us some weird things! How did that LiPO battery get there? I've had this phone for about 15 years and over the last couple of weeks I've converted into a fully functioning Bluetooth headset using an ESP32 microcontroller."

The phone was originally designed to be connected to the Dutch telephone system, dialing out using a rotary input system that is translated into pulses on the line. With many countries having made the move from pulse to tone dialing, and quite a few retiring the plain-old telephone system in favor of IP telephony carried over optical cables, there's not much call for the 1950 other than as a decoration — unless you upgrade it.

Having removed the original hardware, Waleson attempted to get as many features of the phone working under the control of an Espressif ESP32 microcontroller as possible — including the rotary dial. "The buzzer works when you are [called]," Waleson explains. "The rotary dial can be used to dial complete phone numbers, Lifting the horn or putting it down picks up/hangs up [a] call. If no number is dialed you are connected to Google Assistant/Siri. The two [mechanical] indicators indicate Bluetooth usage (bottom) and an active audio connection (top)."

The project is documented in full on Waleson's blog, with source code available on GitHub under an unspecified license.