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Walkie-talkie. Recreational, toy and amateur radio walkie-talkies. Assorted two-way FRS and GMRS walkie talkies with hand mic. A walkie-talkie, more formally known as a handheld transceiver ( HT ), is a hand-held, portable, two-way radio transceiver. Its development during the Second World War has been variously credited to Donald Hings, radio ...
History of radio. The early history of radio is the history of technology that produces and uses radio instruments that use radio waves. Within the timeline of radio, many people contributed theory and inventions in what became radio. Radio development began as "wireless telegraphy". Later radio history increasingly involves matters of ...
A transistor radio is a small portable radio receiver that uses transistor -based circuitry. Following the invention of the transistor in 1947—which revolutionized the field of consumer electronics by introducing small but powerful, convenient hand-held devices—the Regency TR-1 was released in 1954 becoming the first commercial transistor ...
The SCR-536 weighed 5 pounds (2.3 kg) with batteries and 3.85 lb (1.75 kg) without batteries. The unit operated in AM voice mode between 3.5 and 6.0 MHz frequency range on any one of 50 channels. Plug in crystals and coils were used to control the frequency of the receiver and transmitter. The antenna was a 40 inch telescoping rod that slid ...
A portable battery-powered AM/FM broadcast receiver, used to listen to audio broadcast by local radio stations. A modern communications receiver, used in two-way radio communication stations to talk with remote locations by shortwave radio. Girl listening to vacuum tube console radio in the 1940s.
Naval air traffic controller communicates with aircraft over a two-way radio headset A variety of portable handheld two-way radios for private use. A two-way radio is a radio transceiver (a radio that can both transmit and receive radio waves), which is used for bidirectional person-to-person voice communication with other users with similar radios, in contrast to a broadcast receiver, which ...
1898: Marconi opened the first radio factory, on Hall Street, Chelmsford, England, employing around 50 people. 1899: Bose announced his invention of the "iron-mercury-iron coherer with telephone detector" in a paper presented at Royal Society, London. 1899: Tesla experiments with wireless power in Colorado Springs.
Walkie-talkie – a battery-powered portable handheld half-duplex two-way radio, used in land mobile radio systems. [98] Airband – Half-duplex radio system used by aircraft pilots to talk to other aircraft and ground-based air traffic controllers. This vital system is the main communication channel for air traffic control.