The evolution and development of the automobile radio antenna is perhaps one of the most neglected success stories in the automotive industry. Born in the twilight of the last century, it evolved from a simple wire wrapped around a tree branch, to the current heated rear screen or backlite antenna.
Part One (SAE No. 870090) described seven types of antennas in detail, covering the period 1897-1937. It was shown how the early radio engineers, struggling to develop a viable car antenna, had displayed a great degree of creativity and flexibility, from the “firecracker” experiments of Guglielmo Marconi in 1897, to the ingenious systems developed to overcome the problems created by the all-metal Turret-Top vehicles introduced by General Motors in 1934.
In those pioneering days, the United States public was having a love affair with both the automobile and radio broadcasting, so it was no surprise that their marriage did not take long to arrive. Unfortunately only a few of the technicians that experimented with car radios had had any formal engineering degrees or training. Bold men who had been lured to radio while in their teens, they were basically tinkerers who developed their skills by the “cut and try” method. It is a tribute to their ingenuity that some of their achievements are being rediscovered today, proving that many “new” ideas are only as new as the people who conceive them.
The following will review the evolution of the car antenna from the mid-1930s to the current day (Figure 1).