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In the 1980s, Channel Master was the only second source for General Instrument (GI)'s Videocipher II module, a building block for satellite television receivers, under a licensing agreement for which Avnet paid GI a million dollars. The Channel Master 4251, a high-performance parabolic UHF television antenna, stood about seven feet in diameter ...
He served from January 3, 1965 until January 3, 1969. During his tenure in Congress, Resnick took on the American Farm Bureau Federation and a Resnick aide subsequently wrote a book on the subject. He was a champion of civil rights and also supported the Vietnam War .
[4] The system consists of a master antenna and a matching transformer to match the balanced antenna with unbalanced cable and amplifiers. [5] Most antennas have an impedance of around 300 Ω. To convert it to 75 Ω, a matching transformer (or balun) is used. For trunk line isolation, a resistive inductive device known as a splitter is used.
Antenna directivity is the ratio of maximum radiation intensity (power per unit surface) radiated by the antenna in the maximum direction divided by the intensity radiated by a hypothetical isotropic antenna radiating the same total power as that antenna. For example, a hypothetical antenna which had a radiated pattern of a hemisphere (1/2 ...
The Pan-American television frequencies are different for terrestrial and cable television systems. Terrestrial television channels are divided into two bands: the VHF band which comprises channels 2 through 13 and occupies frequencies between 54 and 216 MHz, and the UHF band, which comprises channels 14 through 36 and occupies frequencies between 470 and 608 MHz.
A standard rack-mount headend. Once a television signal is received, it must be processed. For digital satellite TV signals, a dedicated commercial satellite receiver is needed for each channel that is to be distributed by the cable system; these are usually rack-mountable receivers that are designed to take up less space than consumer receivers.
A reconfigurable antenna is an antenna capable of modifying its frequency and radiation properties dynamically, in a controlled and reversible manner. [2] In order to provide a dynamic response, reconfigurable antennas integrate an inner mechanism (such as RF switches, varactors, mechanical actuators or tunable materials) that enable the intentional redistribution of the RF currents over the ...
In radio-frequency engineering and communications engineering, a waveguide is a hollow metal pipe used to carry radio waves. [1] This type of waveguide is used as a transmission line mostly at microwave frequencies, for such purposes as connecting microwave transmitters and receivers to their antennas, in equipment such as microwave ovens, radar sets, satellite communications, and microwave ...