Vintage Regency Transistor Radio, Inside Label Reads Model TR-1G, Clear Case, AM Band, 4 Transistors, Made In USA, Circa 1955 - 1956 by Joe Haupt Via Flickr: The Regency Division of I.D.E.A (Industrial Development Engineering Associates) produced the first practical transistor radio, the TR-1. The company announced the TR-1 on October 18, 1954, and put it on sale in November 1954. Model TR-1G followed in 1955. This clear case model is very rare and dates to around 1955 to 1956. The front of the radio looks like a TR-1 model while having a TR-1G back cover. This radio was given to a marketing company to use in developing recommendations for improving sales of the Regency transistor radio. Regency rejected the recommendations of the marketing company which was allowed to keep this radio. I purchased the radio from an employee of that company.