The U.S. Army Signal Corps' "Dick Tracy" transistor wrist radio (1953)

In 1953, the U.S. Army Signal Corps developed and built a miniaturized wristwatch transistor radio, which captured the fancy of the public. It was a precursor to the transistor radio industry that followed and the personal mobile telephony of today. One Friday, the chief signal officer ordered that we (the Signal Corps Engineering Laboratories) immediately design and develop such a miniaturized transistor radio. We did so by Monday. It was implemented that week and released. The press announced that Dick Tracy had come to life, as the receiver was named the "Dick Tracy", from the comic strip. The radio used three transistors: one point-contact and two junction transistors. Its regenerative circuit provided remarkable sensitivity for excellent reception from stations 40 miles distant. This paper captures the setting and circumstances for development of the "Dick Tracy", its circuit and implementation, its performance and experience, and its impact on the public and on industry, with vignettes surrounding all this.