Abstract

n the pioneering days of radio, my grandfather's job was to lecture to young engineers who were joining Marconi's company. To illustrate that any complex wave form can be broken down into summed simple waves of different frequencies (important in both radio and acoustics), he took wheels of different diameters and attached them with pistons to a clothesline. When the wheels went round, the clothesline was jerked up and down, causing waves of movement to snake along it. The wriggling clothesline was a model of a radio wave, giving the students a more vivid picture of wave summation than mathematical equations could ever have done.