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A comment on Drone Shield – senses the presence of drones via acoustic detection.

Re:Drone Shield – senses the presence of drones via acoustic... by nraynaud on Sunday September 21, 2014 @05:25PM (#8348365)
I guess using a linear output stage instead of a PWM would help avoid detection. Or use a plane instead of a quadcopter, to limit the noise.
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Re:Drone Shield – senses the presence of drones via acoustic... by mafuyu on Sunday September 21, 2014 @05:44PM (#8348425)
I've found it's the propellers themselves that cause the noise, not the PWM junk on the motors.
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Re:Drone Shield – senses the presence of drones via acoustic... by ck2 on Monday September 22, 2014 @02:13AM (#8349482)
It's the same reason they can make helicopters only so quiet, moving that much air with sharp edges is loud.

They poured a fortune into making "stealth" or even just quieter helicopters without much success.

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Re:Drone Shield – senses the presence of drones via acoustic... by jonathantm on Sunday September 21, 2014 @07:07PM (#8348624)
Or glide/dive from a high altitude?
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