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Jun 26

Device not recording


I received the audiomoth at the end of May. As I had someone from the bat conservation trust arriving I thought it would be a good time to set up. The instructions for set up are clear and although the device was placed three times in a known bat locality I did not get any files recorded. The green light flashes but the red light will flash briefly presumably to indicate a begining of a recording duration. I have also followed the instructions on the British Bat Survey webpage and played the tone but getting nothing. The batteries are fine. The SD card is he one supplied with the device and it is correctly formatted. It is probably something daft I am not doing. Any idea?

Hi, Did the LED go green, and then stay green, when the you played the chime tone to the device? If so, then it has the correct firmware installed, and is correctly configured.


If you then move the switch to CUSTOM you should see the green flashing LED whilst the AudioMoth waits until the scheduled recording time. If the green LED is flashing then the batteries are good and the AudioMoth can write to the SD card are okay.


The AudioMoth will start making recordings at 20:00 BST and will stop at 06:30 BST. Whilst it is recording the red LED will be on almost continuously but will be flickering a little. If you are already inside this period when you move the switch to CUSTOM the AudioMoth will wait until the scheduled start time (i.e. the next time that the minutes divisible by 5, such as 20:05 BST or 20:10 BST). The recordings will be 297 seconds long with 3 second gaps regardless of whether there are any bats detecting - there is no triggering mechanism - the AudioMoth makes recordings whether or not there is anything there.


The green light does not stay green. It just blinks every two seconds while I play the chime

Jul 1

Are you using a Mac for formatting cards? I was getting no recordings for some cards. The red and green LEDs would blink once at the proper recording time, then the green LED would resume blinking, waiting for the next recording time. A card formatting problem was discovered:




If not on Mac, maybe there is a utility or similar way to get more formatting details for your cards to check this.

Did this AudioMoth come from the Bat Conservation Trust specifically in order to take part in this year's British Bat Survey? If not it won't have the correct firmware and won't respond to the chime. It sounds like it has the correct firmware, but the best way to check is to download the Time App from the website (https://www.openacousticdevices.info/config). The firmware is displayed when the device is plugged into a USB socket and the switch is in USB position. The correct firmware is AudioMoth-BritishBatSurvey 1.0.1.


Assuming it has the correct firmware, and it sounds like it does if the green LED flashes every two seconds when you put it in DEFAULT mode, then the problem is that it can't hear the chime tone correctly when you play it from the website. Can you hear the sound? It should be medium volume and the AudioMoth needs to be reasonably close to the speaker. Try experimenting at different distances? Are you using a laptop or mobile phone to play the sound? Either should work fine. Large desktop speakers may not reproduce the 20kHz data signal very well.



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