From 1938, radio programs were also transmitted via the telephone line, using the so-called wired radio. During the economy of scarcity of the post-war years, however, there were hardly any listeners. Citizens would build their own receiving devices from the housing of a field telephone, a selenium rectifier, and 2 tubes from radio devices to be able to receive the wired radio signals. This set-up is indicative of the typical do-it-yourselfers of the time, who had already gained relevant radio experience as wartime radio operators.