Tell us about yourself!
Just look for the TTGO T7 ESP32 from the home screen on AliExpress
Have a look at https://www.rtl-sdr.com/shazam-style-automatic-signal-identification-via-the-sigidwiki-database/
Here is a simple SDR bat detection systemhttps://www.rtl-sdr.com/detecting-the-sound-of-bats-with-a-piezo-speaker-and-sdrplay-rsp1a/
Maybe a MEMS microphone fed into an RTL-SDR dongle, operating on the baseband input ie Shortwave That should get a 8bit ADC with Mic for less than $20
Surely a MEMS microphone would work, and with savings an Intel Neural Compute Stick would help with the classification
I want to try a higher voltage with the coils driven by MOSFETs, A 12volt battery pack to feed the Mega(down to 5v) and Coils
While there is a fuse shown in the circuit diagram , there doesn't appear to be a fuse in practice. The IEC can have a fuse but those are normally much larger than the one in the pics. Lack of earthing is also a problem with a metal case. Otherwise I'm sure it works OK
I'm using 40mm PVC duct to elevate my Samsung 360, using short lengths and joiners to get to the desired height. Only 4m long
Magnets that could be screwed on, center hole, might be better
As an ant barrier, ants will not cross a surface with oil, and as this is a jelly it tends to last longer. Stops ants getting into pet food bowls, onto tables etc
I have a similar pair of video glasses and the apparent screen size is more like 5inch not the promised 50inch. Maybe I'm doing something wrong but they are now in my spare parts box ready for a head mounted display like this
Water cooling should improve the efficiency of the device by 10, unfortunately the water would have be running though constantly. There is also the problem of plumbing.
The keyboard is starting to go faulty again , so I will simply speed up plans to build a new scanner using a RPi2 and freqshow software.