Prefixes that are used for radio and television are usually allocated by
ITU
The International Telecommunication Union is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established on 17 May 1865 as the International Telegraph Unio ...
. They also form the basis for, but do not exactly match, aircraft registration identifiers. But in some cases, especially among
amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...
operators other, by ITU unallocated, callsigns are used when operating from disputed areas or countries that are internationally not (yet) recognized.
They can be:
* unofficial - used by individuals without any issued permit
* temporary - issued by local authority
* official - recognized internationally by different organisations
Prefixes for those stations are either unallocated or unavailable by ITU definitions.
ITU unallocated and unavailable call sign prefixes
Unallocated: The following call sign prefixes are available for future allocation by the ITU. (''x'' represents any letter; ''n'' represents any digit from 2–9.)
* E8, E9, H5, J9, O''n'', S4, T9*, U''n'', V9, X''n'', YZ*, Z4–Z7, Z9, 4N*.
(* Indicates a prefix that has recently been returned to the ITU.)
Unavailable: Under present ITU guidelines the following call sign prefixes shall not be allocated .
(''x'' represents any letter; ''n'' represents any digit from 2–9.)
* ''nn'', ''x''0, ''x''1, 0''x'', 1''x'', Q''x''.
* no prefixes beginning with Q are used—they may be confused with
Q code
The Q-code is a standardised collection of three-letter codes that each start with the letter "Q". It is an operating signal initially developed for commercial radiotelegraph communication and later adopted by other radio services, especially ...
s.
* no prefixes with the digits 1 or 0 are used—they may be confused with the letters I or O.
* two digit prefixes (''nn'') are not as yet considered by the ITU.
Table of Non-ITU radio prefixes
See also
*
ITU prefix
*
Amateur radio call signs
Amateur radio call signs are allocated to amateur radio operators around the world. The call signs are used to legally identify the station or operator, with some countries requiring the station call sign to always be used and others allowing the ...
*
Aircraft registration
An aircraft registration is a code unique to a single aircraft, required by Chicago Convention, international convention to be marked on the exterior of every civil aircraft. The registration indicates the aircraft's country of registration, and ...
References
External links
Article: Kosovo - New DXCC entity?Northern Cyprus 1B: radio amaterur or radio pirate?Article: 1A: DX Entity with a 900 Year HistoryOperational Bulletin No. 1149 (1.VI.2018)
{{Telecommunications
Call signs
Amateur radio call signs