This scene replays quite often in our house: my wife has misplaced her cell phone so she asks me to call her. But where did I leave my cell phone? And the race is on! Who will find their phone first to call the other?
[Zapta] solves this problem with his Phone Finder. The system comes in two parts: a base station with WiFi that’s also connected to the house’s phone line, and an arbitrary number of Amazon Dash buttons that trigger dialing commands.
[Zapta] presses a Dash button, which connects over WiFi to the base station. The base station recognizes the MAC address of the button, looks up and dials the corresponding missing cell phone. This solves the need-a-phone-to-find-a-phone problem very neatly, and since Dash buttons are dirt cheap they can be scattered liberally around the house. They’re clearly marked “his” and “hers” suggesting a similar domestic dynamic.
If we were implementing the base station from scratch, we’d probably try to figure out how a single ESP8266 could do all of the heavy lifting, but browsing through [Zapta]’s GitHub and the included circuit diagram (PDF) demystifies the phone-line interface.
In the early days of cordless phones, we used to joke that a solution to losing them would be to attach a string and tie them to the wall. (Luddites!) We’re glad to see [Zapta] take this project in the opposite direction — using technological overkill to solve the unintended problems that arise from technological progress.