2012年12月25日星期二

Two-way radio

2 way radios, its covers a wide range. Here, we will work in ultrashort wave frequency band (VHF30 ~ 300 MHZ, UHF300 ~ 3000 MHZ) radio communication equipment commander-in-chief called radios. According to the state’s relevant actually standard should be called ultrashort wave frequency modulation wireless telephone, people usually will power small, small hand-held wireless telephone is called “radio”, there was people call it “Walkie Talkie “, and will power is great, the volume greater served in car (ship), and other traffic tools or fixed use wireless telephone, also called “the radio”, such as the Taiwan (the machine), Marine platform, fixed platform, base stations, such as the turntable.
Radios used by man is the earliest of the wireless communication equipment, in the early 1930s began to be applied. In 1936 the United States MOTOROLA company developed the first portable radio communication products-” patrol “brand for an am radio receiver, followed in 1940 and for the United States army transport developed the first to weigh 2.2 kilograms handheld two-way radio an am radio, communication distance of 1.6 km. By 1962, MOTOROLA and launched the first weighs only 33 ounces of handheld wireless radios HT200, its appearance called “brick”, size and early mobile phone mobile phone almost. After nearly three-quarters of a century on the development of the application has become widespread, already from professional field to ordinary consumption, from military to civilian expansion.

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