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The British Army's Wireless Set, Number 10, was the world's first multi-channel microwave relay telephone system. [1] It transmitted eight full-duplex (two-way) telephone channels between two stations limited only by the line-of-sight , often on the order of 25 to 50 miles (40 to 80 km).
This led to a microwave relay group being set up in the Research Department under the direction of Gordon Thayer. [ 4 ] On 13 March 1944, AT&T announced they would be installing 7,000 miles (11,000 km) of coaxial cable to carry telephone and television signals, and then extended that in 1950 to 12,000 miles (19,000 km).
Microwave signals are normally limited to the line of sight, so long-distance transmission using these signals requires a series of repeaters forming a microwave relay network. It is possible to use microwave signals in over-the-horizon communications using tropospheric scatter , but such systems are expensive and generally used only in ...
An RF switch or microwave switch is a device to route high frequency signals through transmission paths. RF (radio frequency) and microwave switches are used extensively in microwave test systems for signal routing between instruments and devices under test (DUT). Incorporating a switch into a switch matrix system enables you to route signals ...
Raytheon patented the dielectric heating device, naming it the Radarange, and in 1947 the first commercially available microwave oven hit the market. What started as an 800-pound device priced ...
With improved klystrons and other microwave devices devised during World War II, higher frequencies allowed far more channels on a given link. This allowed a single microwave relay to carry thousands of telephone calls. Bell Labs developed a practical system known as TD-2, produced by Western Electric. The system was designed not only to carry ...
Trans Canada Microwave or Trans-Canada Skyway was a microwave relay system built in the 1950s to carry telephone and television signals from Canada's east coast to its west coast. Built across the nation, the towers ranged in height from nine metres high, to one in northern Ontario that was over 100 metres high.
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