Suppose you are designing a device to transmit information without wires what part of the EM spectrum will your device use and why

My device will use either radio waves or light waves.

Those are the only EM waves I'm equipped to generate.

If I want to get elegant about it, I may use radio waves with

frequencies around 14.1 MHz, because those can be received

many thousands of miles away. I know how to build an effective

antenna to radiate at that frequency, and as a licensed ham-radio

operator, I can do it legally.