Rotary phones might have went out with prohibition, but that doesn’t stop people from tinkering with them. This project allows you to mod a rotary phone to work as a cellular device with a built-in GSM system, as well as a GPS device.

The premise of this project lies in its connection to the GSM network and a Atmega 8 microcontroller. The phone works by sending strings of data to the microcontroller, which will also echo back as a GPS location if it’s desired. The controller then sends the strings to the GSM module. The cool thing is that the phone only expects a call when you lift the headset off the phone.

– Andrew Dobrow

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