I have a few questions about AM, FM and PM. 1. If FM (or PM) radio modifies the frequency of the signal, how is the signal picked up without having to change the frequency constantly? 2. If PM modulates phase, which modulates frequency, what is the difference between PM and FM? 3. Why is AM only used between 535-1700 kHz (and 148.5-283.5 kHz) and FM is only used between 86 and 108 MHz? Why not on higher or lower frequencies? 4. If a radio is tuned to a certain frequency, how come it can pick up other frequencies (sidebands)? 5. Why doesn't the carrier overpower the sidebands (how come we can't hear it, only the sidebands)? Sorry for all of the questions, I'm just starting out with ham radio self-study, and am trying to make sense of it. Thanks!