I built something like this using teensy board. It’s pretty simple. Mine had a button to activate it, and was not nefarious but could have been. Hope this helps

I built something like this using teensy board. It’s pretty simple. Mine had a button to activate it, and was not nefarious but could have been. Hope this helps! https://github.com/joer14/hackers-doorbell https://github.com/joer14/hackers-doorbell