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Diagram of leaky feeder cable. A leaky feeder is a communications system used in underground mines and inside tunnels. [1] Manufacturers and cabling professionals use the term "radiating cable" [2] [3] [better source needed] [4] as this implies that the cable is designed to radiate: something that a typical coaxial cable is generally not intended to do.
Research activity in the area of radio-frequency circuit design has surged in the 2000s in direct response to the enormous market demand for inexpensive, high-data-rate wireless transceivers. [ 2 ] Common types of RF connectors are used for television receivers, two-way radio , certain Wi-Fi devices with removable antennas, and industrial or ...
In a radio antenna, the feed line (feedline), or feeder, is the cable or other transmission line that connects the antenna with the radio transmitter or receiver.In a transmitting antenna, it feeds the radio frequency (RF) current from the transmitter to the antenna, where the energy in the current is radiated as radio waves.
Tempest for Eliza is a program that uses a computer monitor to send out AM radio signals, making it possible to hear computer-generated music in a radio. Video eavesdropping demo at CeBIT 2006 by a Cambridge University security researcher; eckbox – unsuccessful or abandoned attempt in spring 2004 to build an open-source Van Eck phreaking ...
Hijacking incidents have involved local TV and radio stations as well as cable and national networks. Although television, cable, and satellite broadcast signal intrusions tend to receive more media coverage, radio station intrusions are more frequent, as many simply rebroadcast a signal received from another radio station.
The heyday for grid leak detectors was the 1920s, when battery operated, multiple dial tuned radio frequency receivers using low amplification factor triodes with directly heated cathodes were the contemporary technology. The Zenith Models 11, 12, and 14 are examples of these kinds of radios. [8]
In its operation, the circuit demodulates the radio frequency (RF) signal by rectification or square-law detection, and then amplifies this demodulated signal. The capacitor in series with the grid forms a grid-leak detector which allow the grid to cathode to be used as a diode. A high vacuum tube needs a gridleak resistor parallel to the ...
Coronas can generate audible and radio-frequency noise, particularly near electric power transmission lines. Therefore, power transmission equipment is designed to minimize the formation of corona discharge. Corona discharge is generally undesirable in: Electric power transmission, where it causes: Power loss; Audible noise