Sound activated recording, using your Raspberry Pi based bat recorder/detector, is an ideal way of leaving your recorder unattended all night with recordings being triggered by bat calls.
The resulting wav files can be very small, and therefore easy to manually analyse. Spectrograms of each recorded call can quickly be made automatically, assisting in species identification.
I have my Raspberry Pi inside, with just the microphone attached to a 5 metre cable placed outside just underneath a gutter. I used a small funnel in which to house the microphone, with cling-film covering the aperture of the funnel to make it waterproof.
Setting-up Sound Activated Recording
Details on how to set up sound activated recording are here: Sound Activated Recording and latest information (Summer 2019) here: Sound Activated Recording using Audio Injector Ultra Sound Card
Results from Sound Activated Recording
This page shows you what can be achieved with sound activated recording.
Sound Activated Recording with the Multi-function Bat Recorder/Detector
Sound activated recording is also possible to implement in the hand-held multi-function recorder/detector – see here for more details.
Sound Activated Recording with AudioInjector Ultra Sound Card
This page shows the latest information (summer 2019) on sound activated recording.