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New detector set-up (1 Viewer)


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My new "bat detector" this year, mostly cobbled together from old kit around the house, the dodotronic has brought it all together nicely...

*A dodotronic ultramic 384 Evo
*Parabolic reflector from www.parabolicmicrophone.co.uk
*Android tablet running bat recorder app, and handlebar mount
*Various cables, otg cable,
*Bluetooth headphones
(*Plus zoom h2n and external mic pointing into reflector for bird song.)

The zoom and regular mic really amplifies bird song, especially with headphones. I can hear birds that don't even register with my ears.

Similarly, the ultrasonic mic pointing into the parabolic reflector detects bats that don't even register with my previous bat recorder (Ciel 401).

What is less easy to test, is how much the bat detector set up relies on the parabolic reflector, as comparing requires dismantling the set up, by which time the bat has gone. However, with a set of keys jangling, there was a significant improvement with the reflector.


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Registered User
And a typical output, Soprano Pipistrelle, and feeding buzzes.
There is a noticeable band of noise along ~35khz, mostly tuned out of this sonogram, but noticeable on fainter recordings.

Screenshot 2021-05-11 18.49.22.png


Registered User
Took the tablet and ultrasonic mic into nearby woods that are known for Barbastelle, and had 3 very brief, fairly distant passes amongst the Common and Soprano Pipistrelles.
The back garden has a Serotine each evening which is cool.

Only downside I'm getting, is the bat recorder app stops every 5 minutes or so. Not a big deal to stop and start the scanning again, but a minor niggle.

I'm in a conundrum as the android devices are small, easy to use, great battery.. but with this bug.
A Linux or Windows laptop wouldn't have the bug, but would be cumbersome, heavier, and probably less battery life.

(,On this occasion, the Chromebook fails on all fronts! Recognises the mic, but I can't get any apps, or the Linux container to see it)

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