shortcolin
As an experiment @cicely Soldered a MEMS microphone onto a pi pico, and we got it to classify bats using the https://github.com/macaodha/batdetect2 model. Exciting to hear the bat chirps when playing the WAV file slowed down. Will have to write a blog post soon to explain what we did but for now it is getting dark - which means more bats to spy on!
Aug 29, 2025 at 7:52pmWeb
Show threadExtreme ElectronicsAug 29, 2025
@shortcolin @cicely You may find this useful for bat free testing. https://github.com/ExtremeElectronics/AttaHell
GitHub - ExtremeElectronics/AttaHell: Bat Call Simulator for Pipico and 40khz Piezo sounder

Bat Call Simulator for Pipico and 40khz Piezo sounder - ExtremeElectronics/AttaHell

GitHub
Show threadshortcolinAug 30, 2025
@Extelec @cicely Thank you! That is useful to know. Our current best test was sitting on the pavement in front of a car and picking up the ultrasonic parking sensor; this method looks a bit more reliable and elegant!
Show threadExtreme ElectronicsAug 30, 2025

@shortcolin @cicely thankyou...

Difficult to find a good speaker to cover the range. The cheap plastic twearers are the best ive found. Please tell me if you have anything better, or/and how you get on.