Make:

In 2000, I spent a summer living in the woods doing restoration work. I lived in a tent and every night, the bats would come out and I oftened wondered what it would sound like to be a bat and to be able to hear all of the bat-traffic aound my tent. At that time, I had a lot of gadgets and I still daydream of combining them all into one. Who doesn't need a combination cellphone, camera, elecric shaver, gps logger, calendar with the added feature of bat detection? For now, I'm quite happy with the batometer, it makes an uber-geek fashion statement and allows me to listen to the ultrasonic frequencies that bats make when they use echolocation to fly in the dark.

Tony Messina designed the circuit for this project.

"On retirement, I decided to undertake the design of an ultra-portable, personal bat detector. It is small in size, lightweight, easy to build, and can cost as little as $25 in parts. It turned out to be an amazingly simple yet effective circuit so I dubbed it the Simple Bat Detector."

Go to Tony's website and see his excellent documentation.

Once you've put it together, make sure to take a photograph of it and upload it to the MAKE flickr pool.

Note: Carl Weaver suggests that it could also be used to hear really high-pitched mermaid sounds like Darryl Hannah made in the movie "Splash.

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