I am working on a project where I need to determine when a radio transmission happens on an air band frequency. I am currently using a handheld radio, with a voltage detection module hooked to the headphone output, I watch for the voltage to go non-zero and that triggers a counter. For each individual transmission, the counter is increased by 1.
Using a handheld radio is an expensive way to do this. It's also pretty kludgy. What I would like is to have some sort of smaller and simpler receiver that I can specify the frequency on, and which could send a high/low or on/off type signal to the arduino, from which I can count the transmissions.
I have not been able to find many options. Any ideas? Thanks!