Find-a-bat

Projects General Guidance
1

Anyone know of a 40KHz Ultrasonic detector? I'm wanting to make a very simple bat detector for bats that use about a 40KHz echo location, so this is basically half of a range finder where its just the receiver and its always on waiting to detect said frequency.

I was wondering given the jsn-sr04t only has one transducer if it is always listening for example as then I could use that as my 'listening' device.

Thanks

2

Please do not hijack. Thread split.

3

Use an ultrasound microphone, a fast ADC, and some DSP to filter out the correct frequency.

Not Arduino territory.

I'm using this bat scanner for my bat walks; works great.