Components of a Pam 710 portable radio, 1956.

UNITED KINGDOM - MAY 03: 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. When the Pam 710 first appeared 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)