For many early radio listeners, purchasing a receiver which came with a loudspeaker was prohibitively expensive. Instead, they would listen to programmes through headphones. A crystal radio set was a simple and cheap option. It consisted basically of a tuned circuit and a crystal detector, and had no batteries, the power delivered to its headphones all coming from the transmitter. This radio, model No 2, was manufactured by the Brownie Wireless Co of Great Britain Ltd.
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