First, I posted a picture of this small, inexpensive box on December 28, 2019. Briefly, they cost about US$2-5.00. Made in China and available on eBay. Convoluted foam inside top and bottom. I drilled out a hole in the top 7/16 inches and installed a 1/2 inch rubber grommet. Inside the lid I taped part of the original plastic bag all the way around. I placed the microphone directly under the hole in the case. The grommet does two things; secure the AudioMoth in place between the foam layers, and provide just enough of a raised 'bump' to ward off drips of rain that might otherwise ingress. They may help with deflecting wind. I did not have much rumble, but my attention was fixed on owl vocalizations, not wind. I deployed 4 AudioMoths in these boxes over 1138 hours of night recording. I used 14 inch cable ties to secure the unit to a small tree by the tabs, and wrapped the boxes in camouflage stretch tape, available on Amazon. Some deployments were in state parks filled with curious humans, others in remote areas filled with curious wildlife sniffing and poking. I never lost a box or a unit, and none every failed, or came loose from a secured location. I brought the last unit in this morning; it was out for 5 nights, recording 10 hours a night, one of which featured a major storm which dumped 2.5 to 3.5 inches of rain. The unit was completely dry, all 200 fifteen minute recordings were clear, and I did not find the screech-owls I was searching for.
top of page
To see this working, head to your live site.
bottom of page
I got caught again, two inches (5cm) of hard rain. This time two of the units in their cases were pointing up at maybe 30º. Water did get past the plastic barrier in one case but was largely absorbed by the eggshell foam on top of the Moth. The surface of the Moth was damp, and it was 24 hours before I picked them up. There was no damage, and the recordings were clear and intact. Those units which were mounted vertically in their cases were completely dry.
Insects were not a problem since much of the work was done during winter and five days was the longest period of deployment. I used the original bag as the membrane only because I knew it exhibited a decent level of acoustic transparency. I have no reason to believe a grocery store zip-lock type bag would not work just as well, although I was never motivated to make the comparison.
Sorry to hear that the screech-owls were not there this time around. Thank you for sharing your experience with the box. Out of curiosity, did you not have issues of insects moving in from the opening? Also, I understood correctly that you only used the original plastic bag of the AM as "membrane" between the mic and the outside world?