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Gecophone Crystal Set, by GEC, c. 1921
Inventory Number: 80012
Number of documents: 1
Document Type: Miscellaneous Note
Document Heading: Technical Details
Text:
Crystal set radios employed a mineral crystal in delicate contact with a tiny coil of wire known as a 'cat-whisker' to detect broadcast signals. The cat-whisker had to be placed by the user in exactly the right position in contact with a fragment of crystalline galena. Not needing batteries, crystal sets used the power in the radio waves themselves to generate sound through the headphones. When connected up to an aerial wire - about 100ft. being the recommended length - and a 20ft. long earth wire, the set was capable of receiving signals up to 30 miles from a BBC transmitter. This crystal set, despite dating back to the beginning of broadcasting in the UK, is still in working condition and when tested in the GEC Archives picked up 'Virgin' radio. In 1921, this 'listen-in' set (as it was also known) would have cost £9 15s 0d (£9.75).
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