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Medium frequency (MF) refers to radio frequencies (RF) in the range of 300 kHz to 3000 kHz. Radio frequency ( RF) is a Frequency or rate of Oscillation within the range of about 3 Hz to 300 GHz The hertz (symbol Hz) is a measure of Frequency, informally defined as the number of events occurring per Second. Part of this band is the medium wave (MW) AM broadcast band. Medium Wave (MW is a part of the Medium frequency (MF radio band used mainly for AM broadcasting. The MF band is also known as the hectometer band or hectometer wave as the wavelengths range from ten to one hectometers (1,000 to 100 m). A hectometre ( American spelling: hectometer, symbol hm) is a somewhat uncommonly used unit of Length in the Metric system Frequencies immediately below MF are denoted Low-frequency (LF), and the next higher frequencies are known as High-frequency (HF). Low Frequency or LF refers to Radio Frequencies (RF in the range of 30 kHz&ndash300 kHz High frequency (HF radio frequencies are between 3 and 30 MHz.

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Uses and applications

Non-directional navigational radio beacons (NDBs) for maritime and aircraft occupy a band from 190 kHz to 435 kHz, which overlaps from the LF into the bottom part of the MF band. A Non-directional beacon ( NDB) is a Radio transmitter at a known location used as an aviation or marine Navigational aid Low Frequency or LF refers to Radio Frequencies (RF in the range of 30 kHz&ndash300 kHz

500 kHz was for many years the Maritime distress and emergency frequency, and there are more NDBs between 510 and 530 kHz. Since early in the 20th century the radio frequency of 500 Kilohertz ( 500 kHz) has been an international calling and distress frequency for Morse Navtex, which is part of the current Global Maritime Distress Safety System occupies 518 kHz and 490 kHz for important digital text broadcasts. NAVTEX (Navigational Telex is an international automated Medium frequency direct-printing service for delivery of navigational and meteorological warnings and forecasts as The Global Maritime Distress Safety System ( GMDSS) is an internationally agreed-upon set of Safety procedures types of equipment and communication protocols used In recent years, some limited amateur radio operation has also been allowed in the region of 500 kHz in the USA, UK, Germany and Sweden. Amateur radio, often called ham radio, is both a Hobby and a service in which participants called "hams" use various types of Radio communications [1]

Medium waveband radio transmissions are allocated an AM broadcast band from 530 kHz to 1610 kHz with an extension to 1710 kHz in the US. Radio is the transmission of signals by Modulation of electromagnetic waves with frequencies below those of visible Light. Amplitude modulation ( AM) is a technique used in electronic communication most commonly for transmitting information via a Radio Carrier wave

Many home-portable or cordless telephones, especially those that were designed in the 1980s, transmit low power FM audio signals between the table-top base unit and the handset on frequencies in the range 1600 to 1800 kHz. [2]

There is an amateur radio band known as 160 meters or 'top-band' between 1810 and 2000 kHz. Amateur operators transmit CW morse code, digital signals and SSB voice signals on this band. Morse code is a Character encoding for transmitting telegraphic information using standardized sequences of short and long elements to represent the letters numerals Single-sideband modulation ( SSB) is a refinement of Amplitude modulation that more efficiently uses electrical power and bandwidth.

There are a number of Coastguard and other ship-to-shore frequencies in use across the range from 1600 to 2850 kHz. These include, as examples, the French MRCC on 1696 kHz and 2677 kHz, Stornoway Coastguard on 1743 kHz, the US Coastguard on 2670 kHz and Madeira on 2843 kHz. [3] RN Northwood in England broadcasts Weather Fax data on 2618. 5 kHz. [4]

2182 kHz is the international calling and distress frequency for SSB voice maritime communication (radiotelephony) on the marine MF bands. The radio frequency of 2182 kilohertz (kHz is the international calling and distress frequency for voice maritime communication (radiotelephony on the marine MF bands It is analogous to Channel 16 on the marine VHF band.

Lastly, there are aeronautical and other mobile SSB bands from 2850 kHz to 3500 kHz, crossing the boundary from the MF band into the HF radio band. High frequency (HF radio frequencies are between 3 and 30 MHz. [3][5]

See also

References

  1. ^ The 500 KC Amateur Radio Experimental Group
  2. ^ totse.com | How to listen to cordless telephone conversations
  3. ^ a b MF/HF SSB Frequencies
  4. ^ http://www.hffax.de/Northwood-95.txt
  5. ^ http://www.ntia.doc.gov/osmhome/allochrt.pdf U. The electromagnetic (EM spectrum is the range of all possible Electromagnetic radiation frequencies In Telecommunication, a maritime broadcast communications net is a Communications net that is used for international distress calling including international lifeboat The International Telecommunication Union uses an internationally agreed system for classifying Radio frequency signals The Global Maritime Distress Safety System ( GMDSS) is an internationally agreed-upon set of Safety procedures types of equipment and communication protocols used NAVTEX (Navigational Telex is an international automated Medium frequency direct-printing service for delivery of navigational and meteorological warnings and forecasts as S. Government Frequency Allocation Chart

Further reading

External articles

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