
The above is an ultra simplified synopsis of how it works, but that’s the basic idea. Also, keep in mind that there are millions of frequencies upon which these transmissions are broadcast. Think of each frequency as a different radio station. Don’t worry if you aren’t following along at this point; we will break it down further:
- A frequency is a set wavelength and amplitude of a radio signal – think of a single frequency as an individual radio station. For example, you know that in Los Angeles, the frequency of 102.7 on the radio corresponds to KIIS FM.
- A band is a collection of frequencies. So going back to that FM radio example above, all of the radio stations on your car radio that are FM stations are referred to as a band. Thus, the FM band on your car radio is all of the FM frequencies from 87.7 MHz 107.8MHz. As you already know, there are dozens of radio stations (frequencies) in your car radio.
- In your car, you have two bands – an AM band and an FM band. Between the two of them, there are probably a hundred or more possible radio stations.

Now that we’ve got that, let’s consider the humble ham radio for a moment – it contains a staggering 27 bands, and each band has thousands of frequencies! Oh, and you can both receive and transmit on a ham radio, but in your car, you can only receive!