impedance relay
41Burglar alarm control panel — A burglar alarm control panel is a wall mounted unit where the detection devices and wiring of the alarm are ultimately connected and managed. These include devices such as bells, sirens, door contacts, motion detectors, etc. Typical panels are… …
42Reflection seismology — (or seismic reflection) is a method of exploration geophysics that uses the principles of seismology to estimate the properties of the Earth s subsurface from reflected seismic waves. The method requires a controlled seismic source of energy,… …
43Antenna analyzer — An antenna analyzer measuring SWR and complex impedance of a dummy load. MFJ Enterprises Inc. MFJ 269. An antenna analyzer (also known as a noise bridge, RX bridge, SWR analyzer, or RF analyzer) is a device used for measuring the efficiency of… …
44номинальное сопротивление входной цепи электрического реле — …
45Number Five Crossbar Switching System — The Number Five Crossbar Switching System or 5XB switch, designed by Bell Labs and made by Western Electric, was in use in Bell System telephone exchanges from 1948 to the 1980s. Its principal use was as a Class 5 telephone switch, though… …
46Earth leakage circuit breaker — An Earth Leakage Circuit Breaker (ELCB) is a safety device used in electrical installations with high earth impedance to prevent shock.PurposeMany electrical installations have a relatively high earth impedance. This may be due to the use of a… …
47Parabolic antenna — A parabolic satellite communications antenna at Erdfunkstelle Raisting, the biggest facility for satellite communication in the world, in Raisting, Bavaria, Germany. It has a Cassegrain type feed. A parabolic antenna is an antenna that uses a… …
48Opto-isolator — This article is about the electronic component. For the optical component, see optical isolator. Schematic diagram of an opto isolator showing source of light (LED) on the left, dielectric barrier in the center, and sensor (phototransistor) on… …
49List of electrical engineering topics (alphabetical) — This page aims to list, alphabetically, all articles related to the specific discipline of electrical and electronics engineering. For a thematic list, please see List of electrical engineering topics. For the broad field of engineering, see List …
50ARC-5 — The AN/ARC 5 Command Radio Set is a series of radio receivers, transmitters, and accessories used to provide two way Morse code and AM radiotelephone communication for U.S. Navy aircraft during World War II and the years following. It was an… …
