 Chrysler made the all-transistor car radio, Mopar model 914HR, available as an "option" in Fall 1955 for its new line of 1956 Chrysler and Imperial cars, which hit the showroom floor on October 21, 1955.The all-transistor car radio was a $150 option.The Sony TR-63, released in 1957, was the first mass-produced transistor radio, leading to the mass-market penetration of transistor radios.