I have to replace the mems due to the Audiomoth falling into water (see my post from last month). Is it possible to know the type and /or the model used in the Audiomoth?
Thank you!
Hello, Wondering whether anyone has any experience using Audiomoths in very hot climates, please? I am planning on using Audiomoths in north east Brazil where the temperature will easily get to 40-45 deg C and we've experienced trail cams not coping well. I'm planning on placing the devices in shades but can anyone recommend anything else? Many thanks in advance! Nat :-)
The microphone, as I recall, is a Knowles SPM0410 but it is a surface mount device that has numerous pads un the underside which have been reflow soldered to the board, so that removal would be very difficult and replacement in situ almost impossible. Such things can be done but the techniques are difficult to acquire and the equipment would probably cost more than the AudioMoth. A better approach would be to cut the tracks to the microphone (circuit diagrams and board layout are available on here somewhere) and use fine wire-wrap type wire to connect them to a 3.5m jack socket. With a bit of care it is then possible to mount a replacement microphone in the shell of a metal 3.5mm jack plug. Use a small 0.1uF capacitor to connect the microphone signal to the tip, use the ring to provide a 3V (or 5V through a 10k resistor on the AudioMoth board) to provide power for the microphone, with another small tantalum capacitor to ground for decoupling. This provides a useful style of mounted microphone that will plug into any stereo microphone input jack that provides bias voltage as well as into the newly mounted AudioMoth jack. If you are not interested in the ultrasonics other Knowles microphones can be used which are a bit simpler to attach wires to.
Hi, The microphone is a Knowles SPM0408LE5H-TB-6 -
https://www.digikey.co.uk/product-detail/en/knowles/SPM0408LE5H-TB-6/423-1129-2-ND/1992875
The full parts list is here -
https://circuithub.com/projects/OpenAcoustics/AudioMoth/revisions/11676.
As Justin says replacing the microphone is a bit tricky - you'll need to find someone with a hot-air rework station - https://learn.sparkfun.com/tutorials/how-to-use-a-hot-air-rework-station/all. With the hot-air station it's quite straightforward with some experience - just heat up the existing one - remove it with tweezers - place the new one in position and heat up the existing solder until it reflows again.