UNITED KINGDOM - JANUARY 05: When Pam, the first all-transistor radio made in Britain, appeared in 1956, there were already portable valve radios, though their battery demands made them expensive to run. It was very much a luxury item, costing roughly a month's wages, but the use of transistors led, before long, to miniature radios at affordable prices. Sound broadcasts could now be listened to anywhere. (Photo by SSPL/Getty Images)
