High Frequency

High Frequency

High frequency (HF) radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters (ten to one hundred metres). Frequencies immediately below HF are denoted medium frequency (MF), and the next higher frequencies are known as very high frequency (VHF). The HF band is a major part of the shortwave band of frequencies, so communication at these frequencies is often called shortwave radio. Because radio waves in this band can be reflected back to Earth by the ionosphere layer in the atmosphere, called "skip" or skywave propagation, these frequencies can be used for long distance communication, at intercontinental distances. The band is used by international shortwave broadcasting stations (2.310 - 25.820 MHz), aviation communication, government time stations, weather stations, amateur radio and citizens band services, among other uses.

Read more about High Frequency:  Propagation Characteristics, Uses

Other articles related to "high frequency, high, frequency":

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... High frequency vibrating equipment is a shaker whose frame is fixed and the drive vibrates only the screen cloth ... High frequency vibration equipment is for particles that are in this particle size range of an 1/8 in (3 mm) down to a +150 mesh ...
Abraham Esau
... of Berlin, Esau worked at Telefunken, where he pioneered very high frequency (VHF) waves used in radar, radio, and television, and he was president of the Deutscher Telefunken ... From 1953, he was also head of the Institute of High-Frequency Engineering of the German Aeronautical Research Institute ...
High Frequency - Uses
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... low capacitance devices are available with a vacuum between their plates, which allows extremely high voltage operation and low losses ... a capacitor can hold, the dielectric material needs to have as high a permittivity as possible, while also having as high a breakdown voltage as possible ... Paper was used extensively in older devices and offers relatively high voltage performance ...
AN/MPN - Variations
... High Frequency (HF) and Very High Frequency (VHF) communications were provided by the SCR-274 transmitter, and BC-342 receivers ... Ultra High Frequency (UHF) communications were added later via tactical radios normally jeep mounted for use by forward air controllers ...

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