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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.
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]
For low-frequency damping in military applications, this distance is often 60 cm (24 in), while high-frequency panels are as short as 7.5 to 10 cm (3 to 4 in). An example of a high-frequency application would be the police radar (speed-measuring radar K and Ka band), the pyramids would have a dimension around 10 cm (4 in) long and a 5 cm × 5 ...
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency [1] range from around 20 kHz to around 300 GHz.
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.
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
A baseband channel or lowpass channel (or system, or network) is a communication channel that can transfer frequencies that are very near zero. [4] Examples are serial cables and local area networks (LANs), as opposed to passband channels such as radio frequency channels and passband filtered wires of the analog telephone network.
independent of frequency (λc is the cutoff wavelength). On the contrary, when the guiding structure is partly filled with dielectric, the transverse wavenumber kt is a function of frequency, so that Δθ changes as the beam is frequency scanned. On the other hand, with respect to frequency sensitivity, i.e., how quickly the beam angle scans as ...