A US engineer is trying to sell the idea of an open source drone detection system built out of shedloads of Raspberry Pi kits.
The Drone Shield, which is designed by John Franklin, will cost around $60 to $70 to set up. It will combine a, a signal processor, a microphone, and analysis software to scan for specific audio signatures and compare them against what known drones sound like.
Once a match is found, the Drone Shield then sends an e-mail or SMS to its owner and warns him or her to keep their head down.
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