Transportation
edit
Maritime
edit
Merchant and naval vessels are assigned call signs by their national licensing authorities. In the case of states such as
Liberia
or
Panama
, which are
flags of convenience
for ship registration, call signs for larger vessels consist of the national prefix plus three letters (for example, 3LXY, and sometimes followed by a number, e.g. 3LXY2). United States merchant vessels are given call signs beginning with the letters "W" or "K" while US naval ships are assigned call signs beginning with "N". Originally, both ships and broadcast stations were assigned call signs in this series consisting of three or four letters. Ships equipped with Morse code radiotelegraphy, or life boat radio sets, aviation ground stations, broadcast stations were given four-letter call signs. Maritime coast stations on high frequency (both radiotelegraphy and radiotelephony) were assigned three-letter call signs. As demand for both
marine radio
and broadcast call signs grew, gradually American-flagged vessels with radiotelephony only were given longer call signs with mixed letters and numbers.
Leisure craft with VHF radios may not be assigned call signs, in which case the name of the vessel is used instead. Ships in the US still wishing to have a radio license are under
FCC
class SA: "Ship recreational or voluntarily equipped." Those calls follow the land mobile format of the initial letter K or W followed by 1 or 2 letters followed by 3 or 4 numbers (such as KX0983 or WXX0029).
U.S. Coast Guard
small boats have a number that is shown on both bows (i.e. port and starboard) in which the first two digits indicate the nominal length of the boat in feet. For example, Coast Guard 47021 refers to the 21st in the series of 47-foot motor lifeboats. The call sign might be abbreviated to the final two or three numbers during operations, for example:
Coast Guard zero two one
.
Aviation
edit
Originally aviation mobile stations (aircraft) equipped with radiotelegraphy were assigned five-letter call signs (e.g. KHAAQ). Land stations in aviation were assigned four-letter call signs (e.g. WEAL ? Eastern Air Lines, NYC.) These call signs were phased out in the 1960s when
flight radio officers
(FRO) were no longer required on international flights. The Russian Federation kept FROs for the Moscow-Havana run until around 2000.
Currently, all signs in
aviation
are derived from several different policies, depending upon the type of flight operation and whether or not the caller is in an aircraft or at a ground facility. In most countries, unscheduled
general aviation
flights identify themselves using the call sign corresponding to the
aircraft's registration
number (also called
N-number
in the U.S., or
tail number
). In this case, the call sign is spoken using the
International Civil Aviation Organization
(ICAO)
phonetic alphabet
. Aircraft registration numbers internationally follow the pattern of a country prefix, followed by a unique identifier made up of letters and numbers. For example, an aircraft registered as
N978CP
conducting a
general aviation
flight would use the call sign
November-niner-seven-eight-Charlie-Papa
. However, in the United States a pilot of an aircraft would normally omit saying
November
, and instead use the name of the aircraft manufacturer or the specific model. At times, general aviation pilots might omit additional preceding numbers and use only the last three numbers and letters. This is especially true at uncontrolled fields (those without control towers) when reporting traffic pattern positions or at towered airports after establishing two-way communication with the tower controller. For example,
Skyhawk eight-Charlie-Papa, left base
. In commercial aviation, the callsign is usually the ICAO
Flight number
. For example,
Delta Airlines Flight 744
would have the flight number
DL744
and the callsign would be
Delta 744
.
In most countries, the aircraft call sign or "tail number"/"tail letters" (also known as registration marks) are linked to the international radio call sign allocation table and follow a convention that aircraft radio stations (and, by extension, the aircraft itself) receive call signs consisting of five letters. For example, all British
civil aircraft
have a five-letter registration beginning with the letter G, which can also serve for a call sign. Canadian aircraft have a call sign beginning with C?F or C?G, such as C?FABC.
wing-in-ground-effect vehicles
and
hovercraft
in Canada are eligible to receive C?Hxxx call signs, and
ultralight aircraft
receive C-Ixxx call signs. In days gone by, even American aircraft used five-letter call signs, such as KH?ABC, but they were replaced prior to World War II by the current American system of civilian aircraft call signs (see below). One exception to the parallelism between registration and call sign is ultralight airplanes in France, who are not obliged to carry a radio and indeed often don't.
Spaceflight
edit
Radio call signs used for communication in crewed spaceflight are not formalized or regulated to the same degree as for aircraft. The three nations currently launching crewed space missions use different methods to identify the ground and space radio stations; the United States uses either the names given to the space vehicles, or else the project name and mission number. Russia traditionally assigns code names as call signs to individual
cosmonauts
, more in the manner of
aviator call signs
, rather than to the spacecraft.
The only continuity in call signs for spacecraft have been the issuance of "ISS"-suffixed call signs by various countries in the amateur radio service as a citizen of their country has been assigned there. The first amateur radio call sign assigned to the International Space Station was NA1SS by the United States. OR4ISS (Belgium), DP0ISS (Germany), and RS0ISS (Russia) are examples of others, but are not all-inclusive of others also issued.
Broadcasting
edit
Broadcasters are allocated call signs in many countries. While broadcast radio stations will often
brand
themselves with plain-text names, identities such as "
Cool
FM
", "
Rock
105" or "the ABC network" are not globally unique. Another station in another city or country may (and often will) have a similar brand, and the name of a broadcast station for legal purposes is normally its internationally recognised ITU call sign. Some common conventions are followed in each country.
Broadcast stations in North America generally use call signs in the international series. In the United States of America, they are used for all FCC-licensed transmitters.
[2]
The first letter generally is
K
for stations located west of the
Mississippi River
and
W
for eastern stations. Historic exceptions in the east include
KYW
in Philadelphia and
KDKA
in Pittsburgh, while western exceptions include
WJAG
in
Norfolk, Nebraska
, and
WOAI
in San Antonio. All new call signs have been four-character for some decades, though there are historical
three-character call letters
still in use today, such as
KSL
in Salt Lake City,
KOA
in Denver,
WHO
in Des Moines,
WWJ
and
WJR
in Detroit,
WJW-TV
in
Cleveland
,
WBT
in Charlotte,
WBZ
in Boston,
WSM
in Nashville,
WGR
in Buffalo,
KFI
,
KNX
and
KHJ
in Los Angeles, and
WGN
,
WLS
and
WLS-TV
in Chicago. American radio stations announce their call signs (except for rare cases in which would interfere with the broadcast of very long works of classical or opera music) at the top of each hour, as well as sign-on and sign-off for stations that do not broadcast 24 hours. Beginning in the early 2000s, digital subchannels were assigned a -DT# suffix, where # is the subchannel (starting with the number 2).
In Canada, the publicly owned
Canadian Broadcasting Corporation
uses the prefix
CB
; privately owned commercial broadcast stations use primarily
CF
and
CH
through
CK
prefixes; and four stations licensed to
St. John's
by the
Dominion of Newfoundland
government retain their original
VO
calls. In Mexico,
AM radio
stations use
XE
call signs (such as
XEW-AM
), while the majority of
FM radio
and television stations use
XH
. Broadcast call signs are normally four or five alpha characters in length, plus the
-FM
,
-TV
, or
-TDT
suffix where applicable.
In South America call signs have been a traditional way of identifying radio and TV stations. Some stations still broadcast their call signs a few times a day, but this practice is becoming very rare. Argentinian broadcast call signs consist of two or three letters followed by multiple numbers, the second and third letters indicating region. In Brazil, radio and TV stations are identified by a ZY, a third letter and three numbers.
ZYA
and
ZYB
are allocated to television stations;
ZYI
,
ZYJ
,
ZYL
, and
ZYK
designate AM stations;
ZYG
is used for
shortwave
stations;
ZYC
,
ZYD
,
ZYM
, and
ZYU
are given to FM stations.
In Australia, broadcast call signs are optional, but are allocated by the
Australian Communications and Media Authority
and are unique for each broadcast station.
Most European and Asian countries do not use call signs to identify broadcast stations, but Japan, South Korea, Indonesia, the Philippines and Taiwan do have call sign systems. Spanish broadcasters used call signs consisting of
E
followed by two letters and up to three digits until the late 1970s. Portugal had a similar system, their callsigns beginning with
C
; these also ceased to be used in the 1970s. Britain has no call signs in the American sense, but allows broadcast stations to choose their own
trade mark
call sign up to six words in length.
Amateur radio
edit
Amateur radio
call signs are in the international series and normally consist of a one or two character prefix, a digit (which may be used to denote a geographical area, class of license, or identify a licensee as a visitor or temporary resident), and a 1-, 2-, or 3-letter suffix. In Australia, call signs are structured with a two letter prefix, a digit (which identifies geographical area), and a 2, 3 or 4 letter suffix. This suffix may be followed by a further suffix, or personal identifier, such as /P (portable), /M (mobile), /AM (aeronautical mobile) or /MM (maritime mobile). The number following the prefix is normally a single number (0 to 9). Some prefixes, such as Djibouti's (J2), consist of a letter followed by a number. Hence, in the hypothetical Djibouti call sign, J29DBA, the prefix is
J2
, the number is
9
, and the suffix is
DBA
. Others may start with a number followed by a letter, for example, Jamaican call signs begin with 6Y.
When operating with reciprocal agreements under the jurisdiction of a foreign government, an identifying station pre-pends the call sign with the country prefix and number of the country/territory from which the operation is occurring. For example, W4/G3ABC would denote a licensed amateur from the United Kingdom who is operating in the fourth district of the United States. There are exceptions; in the case of U.S./Canadian reciprocal operations, the country/territory identifier is, instead, appended to the call sign; e.g., W1AW/VE4, or VE3XYZ/W1.
Special call signs are issued in the amateur radio service either for special purposes, VIPs, or for temporary use to commemorate special events. Examples include
VO1S
(
VO1
as a
Dominion of Newfoundland
call sign prefix,
S
to commemorate
Marconi
's first trans-Atlantic message, a single-character
Morse code
S
sent from
Cornwall
, England to Signal Hill,
St. John's
in 1901) and GB90MGY (
GB
as a Great Britain call sign prefix,
90
and
MGY
to commemorate the 90th anniversary of historic 1912 radio
distress calls
from
MGY
, the
Marconi station
aboard the famed
White Star
luxury liner
RMS
Titanic
).
[3]
The late
King Hussein
of
Jordan
was issued a special amateur license number,
JY1
, which would have been the shortest possible call sign issued by the Hashemite Kingdom of Jordan.
When identifying a station by voice, the call sign may be given by simply stating the letters and numbers, or using a
phonetic alphabet
. Some countries mandate the use of the phonetic alphabet for identification.
Military call signs
edit
In wartime, monitoring an adversary's communications can be a valuable form of intelligence. Consistent call signs can aid in this monitoring, so in wartime, military units often employ
tactical call signs
and sometimes change them at regular intervals. In peacetime, some military stations will use fixed call signs in the international series.
The
United States Army
uses fixed station call signs which begin with
W
, such as WAR, used by U.S. Army Headquarters. Fixed call signs for the
United States Air Force
stations begin with
A
, such as AIR, used by USAF Headquarters. The
United States Navy
,
United States Marine Corps
, and
United States Coast Guard
use a mixture of tactical call signs and international call signs beginning with the letter
N
.
In the
British military
, tactical voice communications use a system of call signs of the form
letter-digit-digit
. Within a standard infantry battalion, these characters represent companies, platoons and sections respectively, so that 3 Section, 1 Platoon of F Company might be F13. In addition, a suffix following the initial call sign can denote a specific individual or grouping within the designated call sign, so F13C would be the Charlie
fire team
. Unused suffixes can be used for other call signs that do not fall into the standard call sign matrix, for example the unused 33A call sign is used to refer to the
company sergeant major
.
Transmitters requiring no call signs
edit
No call signs are issued to transmitters of the long-range navigation systems (
Decca
,
Alpha
,
Omega
), or transmitters on frequencies
below 10?kHz
, because frequencies below 10?kHz are not subject to international regulations. In addition, in some countries lawful unlicensed low-power personal and broadcast radio signals (
Citizen's Band
(CB),
Part 15
or
ISM bands
) are permitted; an international call sign is not issued to such stations due to their unlicensed nature. Also, wireless network routers or mobile devices and computers using
Wi-Fi
are unlicensed and do not have call signs. On some personal radio services, such as CB, it is considered a matter of etiquette to create one's own call sign, which is called a
handle
(or trail name). Some
wireless networking
protocols also allow
SSIDs
or
MAC addresses
to be set as identifiers, but with no guarantee that this label will remain unique. Many
mobile telephony
systems identify
base transceiver stations
by implementing
cell ID
and mobile stations (e.g., phones) by requiring them to authenticate using
international mobile subscriber identity
(IMSI).
International regulations no longer require a call sign for broadcast stations; however, they are still required for broadcasters in many countries, including the United States. Mobile phone services do not use call signs on-air because the phones and their users are not licensed, instead the cell operator is the one holding the license. However, the U.S. still assigns a call sign to each mobile-phone spectrum license.
In the United States,
voluntary ships
operating domestically are not required to have a call sign or license to operate
VHF radios
,
radar
or an
EPIRB
. Voluntary ships (mostly pleasure and recreational) are not required to have a radio. However, ships which are required to have radio equipment (most large commercial vessels) are issued a call sign.
[4]
Callbooks
edit
A directory of radio station call signs is called a callbook. Callbooks were originally bound books that resembled a
telephone directory
and contained the name and addressees of licensed radio stations in a given jurisdiction (country). Modern Electrics published the first callbook in the United States in 1909.
[5]
Today, the primary purpose of a callbook is to allow amateur radio operators to send a confirmation post card, called a
QSL card
to an operator with whom they have communicated via radio. Callbooks have evolved to include on-line databases that are accessible via the Internet to instantly obtain the address of another amateur radio operator and their QSL Managers. The most well known and used on-line QSL databases include QRZ.COM,
[6]
IK3QAR,
[7]
HamCall,
[8]
F6CYV,
[9]
DXInfo,
[10]
OZ7C
[11]
and QSLInfo.
[12]
See also
edit
References
edit
- ^
"Radio Call Letters"
(PDF)
. U.S. Department of Commerce, Bureau of Navigation. May 9, 1913
. Retrieved
May 19,
2019
.
- ^
"CALL SIGNS/LETTERS - The Museum of Broadcast Communications"
. Museum.tv. Archived from
the original
on March 14, 2016
. Retrieved
March 5,
2016
.
- ^
GB90MGY
Archived
September 8, 2008, at the
Wayback Machine
, Titanic Wireless Commemorative Group, Godalming, Surrey
- ^
"FCC: Wireless Services: Ship Radio Stations: Licensing"
.
wireless.fcc.gov
. Archived from
the original
on March 4, 2016.
- ^
Gernsback, H (May 1909).
First Annual Official Wireless Blue Book of the Wireless Association of America
(PDF)
.
New York
: Modern Electrics Publication
. Retrieved
August 14,
2018
.
- ^
"QRZ.COM"
. Retrieved
November 24,
2010
.
- ^
"Qsl Manager - Qsl Info on-line"
. Retrieved
November 24,
2010
.
- ^
"World Wide HamCall Callsign Server"
. Retrieved
November 24,
2010
.
- ^
"QSL INFORMATION by F6CYV"
. Archived from
the original
on July 20, 2011
. Retrieved
November 24,
2010
.
- ^
"DXInfo, your DX web resource"
. Archived from
the original
on November 11, 2010
. Retrieved
November 24,
2010
.
- ^
"QSL Search machine by OZ7C"
. Retrieved
November 24,
2010
.
- ^
"QSLInfo"
. Retrieved
November 24,
2010
.
Further reading
edit
- United States Federal Aviation Administration,
Aeronautical Information Manual, Official Guide to Basic Flight Information and ATC Procedures,
2004.
Chapter 4, Section 2
External links
edit
Wikimedia Commons has media related to
Call sign
.
- United States Call Sign Policies (Early History)
- United States (FCC) Call Sign Reservation and Authorization System
- FCC amateur radio operator search
- Amateur Call Prefixes
- Internet Radio Uniform Callsign (IRUC) program
- FCCData.org
a database of international telecommunications administrations, searchable by callsign, covering AM, FM, DAB and TV in the United States, Canada, Mexico, the United Kingdom, Ireland, Japan and Australia
- Military Call Sign Database
- Military Call Sign List
- Another Military Callsign List
- Fictional Story About Military Call Signs
Archived
October 29, 2020, at the
Wayback Machine
- Radio-Locator
?A search engine of all of the radio stations in the world with websites, searchable by location, frequency, and call sign
- Broadcasting undertaking callsigns possibly available for assignment
?
Industry Canada
- Call Letter Origins