Question: If an everyday person were to broadcast radio signals into space, how would they do it? What equipment would they need? What kind of licensing would be necessary? — Thomas
Answer: In fact, all radio-wavelength transmissions are broadcast into space. These include AM, FM, TV, and amateur radio signal transmission. I think that the simplest radio transmission equipment that one could acquire would be an amateur radio setup. I think that a good place to start to find out more about amateur (or “Ham”) radio communications systems is to check out the wikipedia page on amateur radio.