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Ultra high frequency acoustic waves
Contemporary Physics, 1962Abstract Two different experimental techniques are available for making ultra-high-frequency acoustic measurements. These are (i) the study of light-scattering (for solids and liquids), and (ii) the use of microwaves (so far mainly restricted to solids).
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High-sensitive ultra-low frequency hydrophone
International Conference on Micro- and Nano-Electronics 2018, 2019In this paper we demonstrate a new prototype of a high-precision ultra-low-frequency hydrophone on the basis of a planar type electrochemical transducer (ECT). We have developed a new planar electrochemical microchip and have invented a mechanical system that allows detecting the alternating pressure at low frequencies up to 0.01 Hz.
Vladimir G. Krishtop +6 more
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The Telegraphist's Equations at Ultra-High Frequencies
Physics, 1935The telegraphist's or long line equations are derived from the Maxwell field equations for ultra-high frequencies. By taking into account retardation and the time rate of change of current, a new circuit parameter is obtained in addition to the four usually found in the conventional low frequency equations.
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Vacuum Tube Electronics at Ultra-High Frequencies
Proceedings of the IRE, 1933Vacuum tube electronics are analyzed when the time of flight of the electrons is taken into account. The analysis starts with a known current, which in general consists of direct-current value plus a number of alternating-current components. The velocities of the electrons are associated with corresponding current components, and from these velocities ...
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Ultra-High Frequency Superconductive Devices
1991Abstract : The objective of this research program was to develop advanced superconducting tunnel junctions for application in superconducting local oscillators and superconducting mixers operating in the Terahertz (0.2 - 2.0 THz) frequency regime. The research was focused on the development of stable, all refractory, high-critical-current-density ...
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A Very-High-Frequency Ultra-High-Frequency Tail-Cap Antenna
Proceedings of the IRE, 1951A description is given of a broad-band vhf-uhf antenna for a small, single-engine type of aircraft consisting of the vertical stabilizer that is tip-fed by the metal tail cap. The resulting antenna covers the frequency range of 100 to 400 mc, is vertically polarized, and has radiation patterns that are essentially omnidirectional.
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Feedback in Very-High-Frequency and Ultra-High-Frequency Oscillators
Proceedings of the IRE, 1950This paper covers a study of feedback considerations in low-power negative-gnrd triode oscillators for the frequency range of 100 to 1,000 Mc. Discussion is mainly confined to oscillators using a single tuned circuit between grid and plate in the modified Colpitts circuit wherein the feedback is provided by the internal tube capacitances.
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An Oscillator for Ultra-High Frequencies
Review of Scientific Instruments, 1938A coaxial line stabilized oscillator that is easily and rapidly adjustable over the frequency range from 70 to 700 Mc per sec. is described. Rugged mechanical construction, substantially complete shielding and coaxial line output connection are other features.
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Ultra High Field MRI: High-Frequency Coils
2007This chapter reviews RF volume, array, and surface coil modeling, design, construction, control, safety, and human in-vivo application examples for field strengths from 4 to 9.4 T. While a comprehensive variety of coils is included, focus is on the transmission line (TEM) technology head, body, surface, and array coils developed by the author over the ...
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Ultra-high-frequency switches and filters
Proceedings of the IEE - Part IIIA: Television, 1952The paper discusses the uses of filters and switches in u.h.f. radiorelay links. Typical requirements for such components are given and possible designs reviewed.As examples, designs of filters and switches used in the London-Birmingham television radio-relay link are given in detail. The switch employs resonant stub-lines placed in shunt with the main
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