Hi Alison, I'd be happy to help. What advice do you need?

Hi Douglas, You can find the datasheet for AudioMoth Dev on the website here. The connector pinouts are shown in Figure 1 and described on page 3. Thanks, Andy

Hi Hemanth, Firmware-basic has a Wiki description, however, if you wanted to write your own firmware a better place to start is the AudioMoth-Project. The Wiki for this describes getting started a little better. Andy

The metadata will be there, but it may take a while to load on Mac if you have many large files.

The soldering looks good to me. Do both the modified SPM0204UD5 with external circuit and Animal sound Labs ME4-em have the same issue. Does the AudioMoth external mic work with any other electret condenser microphones you have? Might need the wiring you used to connect these mics up to the 3.5mm jack to diagnose further. For diagnostics, @Alex Rogers has a nice test - here's the video from twitter. When AudioMoth switches between internal and external microphone, you can see it closing the current file and starting a new file each time the microphone is changed, this works best when recording at 192kHz. You can see the files close whenever the LED stops flashing. Does your unit do this?

Glad we got to the bottom of it. Andy

Hi Richard, That's good to know. If that's the case it's most probably the battery. In the WAV comments in the shorter recordings it should state the reason for stopping as low battery voltage. The 0KB files result when the AudioMoth has opened a file but was not able to close it. This normally happens due to the battery running down during a recording. The 'Enable low-voltage cut-off' option attempts to prevent this by stopping recordings early due to the the low voltage but it is still possible for the write to fail at low voltages depending on the type of SD card.

12V is pushing the AudioMoth power regulator quite hard and for longer recordings a 12V supply will cause high temperatures of >54 degrees C above ambient at the regulator, possibly causing it to stop working at high ambient temperatures. Have you considered using a lower voltage battery? 6V lantern batteries would work well.

Hi Richard, I have a feeling this could be an SD card issue. Are you deleting the files from the SD card each night? As SD cards fill they take longer to open and close files. It might be that your SD card is getting full and needs reformatting. Let us know if that fixes it, Andy

How often do they loose power? What recording schedule and configurations are you using? Could you post the CONFIG.TXT file.

Hi David, It might be worth re-flashing firmware 1.6.0 again, however, when you do it make sure the batteries are removed during the flash process? The device will need a power cycle after re-flash too so make sure the USB is disconnected before putting the batteries back in. Let us know if this solves the issue. Andy

For step 4 - what do the LEDs do when you switch between CUSTOM and DEFAULT? Do your other units work okay?

Are there any signs of weather damage on the device, such as water ingress or corrosion?

Hi Martin, The "Minimum trigger duration" sets the amount of time audio samples are saved when the amplitude of a signal goes over the threshold. This could be useful if you wanted to record the decaying tail of a loud impulse, such as a gunshot, or to record the quieter calls in a whole bat pass. For the gunshot example if you selected a "Minimum trigger duration" of 0s with a 50% amplitude threshold it would only record the samples that go over 50%. However if you selected a"Minimum trigger duration" of 2s with a 50% amplitude threshold it would record the 2s of the gunshot after the triggered event, which might include important information, such as the quieter tail as the impulse sound decays. I hope that answers it. Andy

Hi Cristian, I think you'll never need to put the switch in DEFAULT position for your application. You can ignore this switch position when off-loading the work. If you need to replace the batteries, the time will need to be reset. To set the time using the smartphone app you could: 1) leave the switch position in CUSTOM, then when you insert the batteries AudioMoth will be waiting for the chime sound from the smartphone app or 2) you could insert the batteries when the switch is in USB/OFF. When you move the switch to CUSTOM, AudioMoth will be waiting for the chime sound from the smartphone app. Although the time is lost when batteries are removed, the configuration settings are persistent. It's therefore not necessary to use the configuration app again with the computer after the first configuration. After the first configuration the smartphone app can always be used to set the time. It isn't necessary to set "Always require acoustic chime on switching to CUSTOM" to use the smartphone app chime, but the time will need to be reset or the batteries will always have to be removed and re-inserted to use the smartphone app again. Thanks, Andy

Hi Cristian, You are correct that when the batteries are removed the time will be lost. You must set the time again if you want AudioMoth to record with your schedule and at the correct time. You can set the time in any of these three ways: 1) with the acoustic chime on smartphone AudioMoth App, 2) by USB using the AudioMoth Time App and 3) by USB using the AudioMoth Configuration App. To set the time with the smartphone AudioMoth App, using the acoustic chime, the time must be reset (i.e. remove and reinsert the batteries) the AudioMoth switch must be in the CUSTOM position to set the time with the chime. Note: the DEFAULT switch position is designed for hand held recording, or recording on the fly when the AudioMoth time isn't set. in DEFAULT position AudioMoth will record continuous WAV files even without the time being set. The "requiereAcousticConfig" set to true, forces the user to set the time using the smartphone AudioMoth App using the chime even if the time hasn't been reset. I hope this helps, Andy

Hi Silvy, I'll try my best to answer these for you. (i) the sensitivity of the acoustic transducer, which defines how much voltage is generated per unit of sound pressure. The MEMS mic on AudioMoth 1.1.0 has a sensitivity of -18 dBV/Pa, this is measured when used together with the MEMS output amplifier set to a gain of 10. Here is the MEMS mic data sheet for your reference. (ii) the amount of additional voltage gain applied by the pre-amplifier. At the mid gain setting this is 15, below are the gain values of the other gain settings corresponding to the radio buttons in the AudioMoth Configuration App. Gain 0 Min 4.33 1 7 2 Med 15 3 25.1 4 Max 30 (iii) the ADC input voltage which corresponds to the maximum amplitude that can be represented in the audio files. On AudioMoth 1.1.0 the full 16-bit 0 to 65535 amplitude range corresponds to 0V to 3.3V. I hope this helps, Andy

Yep @Edwin Houwertjes is correct. AudioMoth 1.0.0 and 1.1.0 use the SPM0408LE5H - datasheet here. AudioMoth 1.2.0 uses the SPU0410LR5H - datasheet here.

The cases are available for immediate purchase on the GroupGets store and LabMaker store. GroupGets add the case as an optional extra on AudioMoth campaigns at a reduced cost.

The IPX7 case is completely waterproof so should be fine if the case is closed in a dry environment.