BirdNet Systems Testing #2: a critical review from AI

I'm still troubled by my initial test results

And I haven't made any progress on further testing, 

so I decided to get a second opinion.

BirdNet Systems Testing #1

I thought this would be easy

 Just run BirdNet-Pi alondside BirdNet-Go

Then choose which system to use in the future.

BirdNet-Pi: USB audio module testing

I've bought a couple more modules

so thought I'd do some tests to compare performance.

This post concerns the use of USB audio modules in connection with miniature electret microphone capsules.

BirdNet-Pi: more thoughts on microphones & audio

There's a lot of talk on the Github Discussions page about microphone quality.

So naturally I have been giving the matter some consideration and have conducted a few simple checks.

BirdNet-Pi: portable operation, mics & bird dogs

Its been an interesting couple of weeks.

I've experimented quite a bit with my BirdNET-Pi system and even built a second system.

BirdNet-Pi: intro, install, use

Which bird species visit our garden?

 

BirdNET-Pi may not fully answer that question.

But it may reveal some unexpected visitors.

Bat Call Logger: Wolfson audio card frequency response

Having got my Wolfson Audio card working happily with a Raspberry Pi 2, I decided to try and check the frequency response.

As this card is described as a 'audio card' and the only figures I've seen relate to the audible range, I didn't have high expectations regarding its use in my Bat Call Logger.

Anyway, to find the answer, it was just a question of setting up some test gear and running a few checks.

Bat Call Analysis: second thoughts

I'm still trying to reconcile my bat call recordings with the data provided in the Jon Russ book "British Bat Calls".

This caused me to question whether my home-brew bat detector was a reliable witness.

Just how much faith can I have that my FD detector is producing sensible recordings?

Bat Call Logger: the hardware

My bat call logger combines a frequency division bat detector with a Pi based audio recorder.

Recordings are simply triggered by a short stream of pulses from the detector (i.e. "activity").

Having spent a bit of time trying to optimise the hardware, I now need to document what I've done, before I forget why I've done it!

Bat Detector: electret microphones

Building your own Bat Detector is a relatively easy electronics construction project.

The tricky bit can be locating a suitable transducer or microphone that has a useful frequency response into the ultrasonic range used by common bats.

During the last few weeks I have been testing a number of devices, and here are my notes.