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The complete molecular structure for MLA, correct in all but one detail, was first published by Kuzovkov and Platonova in 1959. [12] This structure, supported in part by X-ray crystallography (considered usually to be a "definitive" analytical technique) of a chemical derivative of MLA performed by Maria Przybylska, [13] was accepted as correct until the early 1980s.
Small-loop receiving antennas are also almost always resonated using a parallel-plate capacitor, which makes their reception narrow-band, sensitive only to a very specific frequency. This allows the antenna, in conjunction with a (variable) tuning capacitor, to act as a tuned input stage to the receiver's front-end, in lieu of a preselector.
The antenna used on the ASR-9 was a state of the art horned shaped reflector that forms two cosecant-squared beams to allow high elevation gain, as well as coverage up to forty-two degrees in elevation coverage. The two beams that pulse from the ASR-9 are nearly identical; however, a minimal displacement in height between the two beams causes a ...
A 20-meter-long T²FD antenna, covering the 5-30 MHz band. The T ilted T erminated F olded D ipole ( T²FD , T2FD , or TTFD ) or B alanced T ermination, F olded D ipole ( BTFD ) - also known as W3HH antenna - is a general-purpose shortwave antenna developed in the late 1940s by the United States Navy .
A monopole antenna is a class of radio antenna consisting of a straight rod-shaped conductor, often mounted perpendicularly over some type of conductive surface, called a ground plane. [1] [2] The current from the transmitter is applied, or for receiving antennas the output signal voltage to the receiver is taken, between the monopole and the ...
A whip antenna is an antenna consisting of a straight flexible wire or rod. The bottom end of the whip is connected to the radio receiver or transmitter. A whip antenna is a form of monopole antenna. The antenna is designed to be flexible so that it does not break easily, and the name is derived from the whip-like motion that it exhibits when ...
[23] [17]: p.19, 260, 331–332 [25] The two sides of the antenna were connected to an induction coil (Ruhmkorff coil) (T) a common lab power source which produced pulses of high voltage, 5 to 30 kV. In addition to radiating the waves, the antenna also acted as a harmonic oscillator ( resonator ) which generated the oscillating currents.
An MWA antenna consists of a four by four regular grid of dual-polarization dipole elements arranged on a 4m x 4m steel mesh ground plane. Each antenna (with its 16 dipoles) is known as a "tile". Signals from each dipole pass through a low noise amplifier (LNA) and are combined in an analogue beamformer to produce tile beams on the sky ...