More bat tracking and thoughts on a Batto Mark-III

We recently took a trip to the east coast of Tassie for the summer holidays. Something I was keen to do was to try out the MarkII at low frequencies by searching for Bitterns, so one evening I put out the MarkII at Moulting Lagoon together with an AudioMoth recorder. No luck with the Bitterns but there were plenty of bats and I was able to get some nice tracks. Here’s one that turned out really well:

I still have some work to do to improve the direction-finding algorithm and I think I can improve the calibration too. Things are pretty reliable when the bat calls span a good frequency range but narrow-band signals are a little more challenging. I’m also experimenting with different microphone configurations, which may help here too.

The Batto Mark-III?

I’m beginning to think about a MarkIII recorder that would have 6 microphones and provide distance as well as direction, for bats at least. The Teensy 4.1 looks like a good candidate for the controller board as it can support that number of mics (or more).