3 days ago · It uses frequencies in the very high frequency (VHF) band from 108.00 to 117.95 MHz. Developed in the United States beginning in 1937 and deployed by 1946, VOR is the standard air navigational system in the world,   used by both commercial and general aviation.
4 days ago · High-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder introduced in World War II. High frequency refers to a radio band that can effectively communicate over long distances; for example, between U-boats and their land-based headquarters. HF/DF was primarily used to catch enemy radios while they transmitted, although it was also used to locate friendly aircraft as a navigation aid. The basic technique remains in use to
6 days ago · Conversely, at very high frequency and ultra high frequency and above, these sources are often lower, and thermal noise is usually the limiting factor. In the most sensitive receivers at these frequencies, radio telescopes and satellite communication antennas, thermal noise is reduced by cooling the RF front end of the receiver to cryogenic ...
3 days ago · Very high frequency electric current causes tissue burning, but does not penetrate the body far enough to cause cardiac arrest (see electrosurgery). Also important is the pathway: if the current passes through the chest or head, there is an increased chance of death.
The basic setup is an AC power supply that provides electricity with low voltage but very high current and high frequency. The workpiece to heat is placed inside an air coil driven by the power supply, usually in combination with a resonant tank capacitor to increase the reactive power. The alternating magnetic field induces eddy currents in the workpiece.
5 days ago · A high-voltage, direct current (HVDC) electric power transmission system (also called a power superhighway or an electrical superhighway) uses direct current (DC) for the bulk transmission of electrical power, in contrast with the more common alternating current (AC) systems. Most HVDC links use voltages between 100 kV and 800 kV.
Apr 10, 2021 · Li-Fi (also written as LiFi) is a wireless communication technology which utilizes light to transmit data and position between devices. The term was first introduced by Harald Haas during a 2011 TEDGlobal talk in Edinburgh.
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In the following sound file first is a POCSAG 512 sound then the second is POCSAG 1200. Each of POCSAG's 3 speed modes: POCSAG 512 POCSAG 1200 POCSAG 2400
Note: In many of these regions, the paging frequencies and bands listed below are shared with other radio services, including land mobile two-way radio. In some areas of the United States, the VHF/UHF paging bands listed below are used for land mobile communications. The low-band 35 MHz/43 MHz frequencies and 929-931 MHz frequencies are exclusively allocated to the paging services in the USA. In the United States, 27.255 MHz is available for unlicensed paging and telemetry services under Part 95 of the FCC rules (sections 95.207 and 95.210) on a shared basis with the CB radio service. The UHF (454-467 MHz) allocations are often "interleaved" with land mobile services. For example, 462.850 MHz is used for paging, while adjacent frequencies 462.8375 MHz and 462.8625 MHz are used for low-power business radio service communications. Same goes for the "high side" of those allocations. 467.750 MHz is often used for low-power on-site paging in restaurants, etc, while 467.7625 MHz is a heav...
This is a website that contains a POCSAG encoder for the soundcard. Please translate the page first, as its in German. You are able to type in 7-digit addresses, function numbers 1-4, and message types of alphanumeric, numeric and tone only messages. 5 messages max in the demo version. Runs on windows. Please extract first. There is also a full paid version as well, for additional features. http://www.dsp4swls.de/sorfmon/sorfmon.html
6 days ago · A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor, which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the lamp to glow.
3 days ago · 156.525 MHz MegaHertz (MHz) 10^6 Hz VHF Very High Frequency (30-300 MHz) Channel 70 MF Medium Frequency (300-3000 kHz) / HF High Frequency (3-30 MHz) Distress and urgency 2187.5 kHz KiloHertz (kHz) 10^3 Hz
- related to: Very high frequency wikipedia