How come FM radio goes from 87.1-107.9 and its all odd numbers?
On your FM dial while you are tuning stations the frequency changes in what is known as ‘steps’. For an example, 87.1…87.3…87.5 are commonly known as ‘steps’. If you want to know the technical side why they are spaced out in the order in frequency is so not to interfere. Meaning that one FM station’s transmitter tower from another FM tower is distanced from each other so not to interfere with each other with the bandwidth steps of 200 kilohertz (KHz) and distance of radio transmitters. These ‘steps’ of 200 KHz are commonly found on vechicle FM receivers and some versions of receivers can be changed from U.S. to european versions. Meaning that should the car be relocated to an european country the ‘steps’ can be changed to fix the FM stations that don’t follow the united states frequency steps. Every frequency in the radio spectrum is allocated or fixed on a plan devised by the FCC giving each spectrum frequency a use for a certain device.
