a radio receiver in which semiconductor devices, primarily transistors and semiconductor diodes, are used for the amplification, frequency conversion, and detection of signals. The term “transistor radio” was introduced during the 1950’s, when transistors first came into industrial use and were employed in various types of receivers, such as radio broadcast, television, and communications receivers.

Transistor radios have been improved so as to broaden the range of usable frequencies, increase the power of the transistors, enhance the stability of the electrical characteristics of the transistors, and improve performance. For example, transistor radios for audio broadcasting were originally produced mainly for the reception of amplitude-modulated signals in the kilometer, hectometer, and—since the 1960’s—decameter wavelength ranges. The late 1960’s saw the development of all-wave receivers, which permit the reception of frequency-modulated ultrashort-wave signals. In the 1970’s the majority of commercially produced radio broadcast receivers were transistor radios. The advantages of transistors, namely, their smallness, low supply voltage, and low power consumption, have made it possible to reduce substantially the size and weight of receivers and to power the receivers by means of miniature batteries housed within the receiver casing. As a result, portable, pocket, and miniature transistor radios have been produced for mass distribution.

With the development of microelectronics, transistor radios based on discrete elements (for example, transistors and diodes) are being replaced by transistor radios in which modules and integrated microminiature electronic devices are used (seeINTEGRATED CIRCUIT. The use of microelectronics improves the quality of transistor radios and makes it possible to introduce such operating conveniences as automatic tuning, finger-touch control, and digital frequency display.