Website · Live simulator · Build it on a breadboard · Build the full unit · Photos and videos
Detection and alert only. No jamming, no interception, no countermeasures, ever.
A 91 mm box with four microphones, an ESP32-S3, an e-paper screen and a LoRa radio. It listens for the harmonic comb a multirotor makes and when it hears one it beeps, flashes red, buzzes, writes the time to a screen that survives a power cut, and tells every other unit on the network.
If you want the short illustrated version, or to watch the detector work on a sound field you control, that is what the website and the simulator are for. This page is the long version, and everything needed to build one is in this repository.
| measured detection, hovering airframe, light wind |
from first sound to alarm |
false alarms in field sessions so far |
on one battery charge |
parts for a full unit |
Understand it: The problem · What the device does · How it works · Radio · Power · Range and testing
Build it: Two ways to build it · Breadboard guide · Full unit guide · Flashing · Running several units
Everything else: Photos and videos · Test results · Deploying · Contributing · Scope · Licence · A note from Agam
Files: firmware · reference detector · PCB, BOM and placement · printable enclosure · test audio · website source
Nearly all drone detection listens for radio. It finds the control link between the pilot and the aircraft, decodes it, and reports where both are. It works well, and it has one hard failure: the drone has to transmit.
A fibre-optic FPV drone does not. It trails a thread of glass back to its operator, video comes down the fibre, control goes up it, and the radio spectrum stays silent. There is nothing to find and nothing to decode.
What it cannot hide is four motors spinning propellers. A 7 in three-blade propeller on a 2807-class motor puts a precisely structured comb of harmonics into the air, spaced by the blade-passage rate, and that spacing is set by physics the airframe cannot switch off. VolAnti listens for that structure.