Wednesday, 17 April 2024, 10:33 PM
Site: edulabs.org academy
Course: Activity Examples (Activity Examples)
Glossary: Electronics (Mike Jaroch)
H
HEATERSame as a FILAMENT [6]. |
HEIGHT-FINDING RADARA radar that provides target altitude, range, and bearing data [18]. |
HELIX(1) A spirally wound transmission line used in a traveling-wave tube to delay the forward progress of the input traveling wave [11]. (2) A large coil of wire. It acts as a coil and is used with variable inductors for impedance matching of high-power transmitters [17]. |
HELIX HOUSEA building at a transmitter site that contains antenna loading, coupling, and tuning circuits [17]. |
HENRYThe electromagnetic unit of inductance or mutual inductance. The inductance of a circuit is 1 henry when a current variation of 1 ampere per second induces 1 volt. In electronics, smaller units are used, such as the millihenry (mH), which is one-thousandth of a henry (H), and the microhenry (μH) which is one-millionth of a henry [2]. |
HERTZA unit of frequency equal to one cycle per second [2]. |
HERTZ ANTENNAA half-wave antenna that is installed some distance above ground and positioned either vertically or horizontally [10]. |
HETERODYNE DETECTIONThe use of an a.f. voltage to distinguish between available signals. The incoming cw signal is mixed with locally generated oscillations to give an a.f. output [12]. |
HETERODYNING(1) The process of mixing two frequencies across a nonlinear impedance [12]. (2) The process of mixing the incoming signal with the local oscillator frequency. This produces the two fundamentals and the sum and difference frequencies [17]. |
HEXADECIMALSame as SEXADECIMAL. A number system with a base of sixteen; also pertains to conditions, choices, or selections that have sixteen possible values or states [13]. |