Utility station
Encyclopedia
The term utility station is used to describe fixed radio broadcasters disseminating signals that are not intended for reception by the general public (but such members are not actively prohibited from receiving). Utility stations, as the name suggests, do broadcast signals that have an immediate practical use, by means of analog or usually digital modes; most often utility transmissions are of a "point-to-point" nature, intended for a specific receiving station. Utility stations are most prevalent on shortwave frequencies, though they are not restricted to the shortwave frequencies.
and sending synoptic codes, or weather charts are sent using radiofax
, which are used by mariners and others. Airports make voice weather broadcasts on HF
, known as VOLMET
. Some examples include New York Radio, which broadcasts weather information for locations in the eastern United States, or Shanwick Radio, which does the same for Europe.
HF frequencies are still often used for trans-oceanic air traffic control.
News agencies previously used RTTY for news stories, and, less commonly, radiofax for the images, although is no longer done. Satellite communications and the Internet have replaced HF for this application.
Many maritime radio services are often known as utility stations, including as ship-to-shore and vice-versa telephony and error-controlled radioteletype such as SITOR
.
Military use of shortwave is also common, but nearly all transmissions are encrypted, with voice encrypted using modes such as ANDVT
. Data transmission may make use of encrypted RTTY, use Link-11 for radar tracking data, or use of Automatic link establishment
modes to set up communication links automatically.
Some utility stations are on other frequency bands, including NOAA Weather Radio, traveler information stations, and the like; other utility-type signals are piggybacked on FM broadcast subcarriers
.
Examples of utility station and modes
One common use of utility stations is disseminating weather information. Weather information is often broadcast using RTTYRadioteletype
Radioteletype is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations, later superseded by personal computers running software to emulate teleprinters, connected by radio rather than a wired link.The term radioteletype is used to...
and sending synoptic codes, or weather charts are sent using radiofax
Radiofax
Radiofax, also known as weatherfax and HF fax , is an analogue mode for transmitting monochrome images. It was the predecessor to slow-scan television...
, which are used by mariners and others. Airports make voice weather broadcasts on HF
High frequency
High frequency 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 . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency...
, known as VOLMET
VOLMET
VOLMET, or meteorological information for aircraft in flight, is the term applied to a worldwide network of radio stations that broadcast TAF, SIGMET and METAR reports on shortwave frequencies. In some countries, VOLMET stations broadcast on VHF frequencies too. Reports are sent using automated...
. Some examples include New York Radio, which broadcasts weather information for locations in the eastern United States, or Shanwick Radio, which does the same for Europe.
HF frequencies are still often used for trans-oceanic air traffic control.
News agencies previously used RTTY for news stories, and, less commonly, radiofax for the images, although is no longer done. Satellite communications and the Internet have replaced HF for this application.
Many maritime radio services are often known as utility stations, including as ship-to-shore and vice-versa telephony and error-controlled radioteletype such as SITOR
SITOR
SITOR is a system for transmitting text messages. Although it uses the same frequency-shift keying modulation used by regular radioteletype , SITOR uses error detection, redundancy, and/or retransmission to improve reliability.There are two SITOR modes:* SITOR-A is used for point to point links...
.
Military use of shortwave is also common, but nearly all transmissions are encrypted, with voice encrypted using modes such as ANDVT
ANDVT
The Advanced Narrowband Digital Voice Terminal is a secure voice terminal for low bandwidth secure voice communications throughout the U.S. Department of Defense. Devices in the ANDVT family include the AN/USC-43 Tactical Terminal , the KY-99A Miniaturized Terminal , and the KY-100 Airborne...
. Data transmission may make use of encrypted RTTY, use Link-11 for radar tracking data, or use of Automatic link establishment
Automatic link establishment
Automatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system, that enables the radio station to make contact, or initiate a circuit, between...
modes to set up communication links automatically.
Some utility stations are on other frequency bands, including NOAA Weather Radio, traveler information stations, and the like; other utility-type signals are piggybacked on FM broadcast subcarriers
Subsidiary Communications Authority
Subsidiary Communications Authorization in the United States, and Subsidiary Communications Multiplex Operation in Canada, is a subcarrier on a radio station, allowing the station to broadcast additional services as part of its signal.-Background:"Subsidiary Communications Authorization" is the...
.
External links
- Utility World with various sound samples of utility modes
- KB9UKD Digital Modes with mostly non-HF utility modes samples