SHEILA TERRY / SCIENCE PHOTO LIBRARY SHEILA TERRY / SCIENCE PHOTO LIBRARY
Crystal radio set. This radio receiver was built in c.1926 by the Brownie Wireless Company of Great Britain Ltd. It functions without the need for a power supply. An antenna (not seen) picks up radio signals and passes them down a wire in the form of an electric current. A crystal of lead sulphide (also known as galena, bottom centre) is housed in the metal case at upper centre. This gives the set its name and allows the current from the antenna to pass through in one direction towards a set of headphones or a loud speaker (not seen). These contain a solenoid that moves in response to the electrical current, causing them to vibrate and produce sound.
Model release not required. Property release not required.