Figure 1.--This image is dated 1935 at the Walden school. Of course by 1935 modern radio sets with vacuume tubes were available. This may be a school projects where the boys built crystal sets as part of school science project. Notice the battery.

Early radio listerners used broadcast "detectors" (crystal sets) to receive the broadcast. The basic detector obtained its energy from the transmitted signal. Only headphone reception was possible (figure 1). Crystal set listening was an individual experience with headsets. It was possible to plug more than one headset in, but still with the headsets on, convesation and comments were difficult. Radio listening with a crystal set was sill an individual activity. Boys are always interested in technology. Boys of the period were very keen on radio as a hobby. For some reason girls were much less interested. (This has not changed greatly. In our modern age, boys show a much greater interest in computers than boys.) Boys also liked radio since it brought them in touch with far-flung places and people. Soon a popular activity for boys was building a crystal set. An additional source of electricity was not needed for a basic crystal set. There were exceptions. A detector with rectifier material needed additional bias voltage. Good detectors had the ability to separate transmissions and were capable of long-distance reception.

Created: December 30, 2003
Last updated: December 30, 2003