APRS Calling is a manual procedure for calling stations on the
Automatic Packet Reporting System
Automatic Packet Reporting System (APRS) is an amateur radio-based system for real time digital communications of information of immediate value in the local area. Data can include object Global Positioning System (GPS) coordinates, non-directi ...
(APRS) to initiate communications on another frequency, or possibly by other means. It is inspired by
Digital Selective Calling
Digital selective calling (DSC) is a standard for transmitting predefined digital messages via the medium-frequency (MF), high-frequency (HF) and very-high-frequency (VHF) maritime radio systems. It is a core part of the Global Maritime Distres ...
, a part of the
Global Maritime Distress Safety System
The Global Maritime Distress and Safety System (GMDSS) is a worldwide system for automated emergency signal communication for ships at sea developed by the United Nations' International Maritime Organization (IMO) as part of the SOLAS Convention. ...
. It also builds on existing digital procedures inherited from
morse code
Morse code is a telecommunications method which Character encoding, encodes Written language, text characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''. Morse code i ...
and
radioteletype
Radioteletype (RTTY) is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations connected by radio rather than a wired link. Radioteletype evolved from earlier landline teleprinter ...
operation.
[Combined Communication Electronics Board (CCEB). ''Communications Instructions ACP 131 (F) Operating Signals''. Combined Communications-Electronics Board, 2006, p. 2-25.] ITU
The International Telecommunication Union (ITU)In the other common languages of the ITU:
*
* is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established ...
Q code
The Q-code is a standardised collection of three-letter codes that each start with the letter "Q". It is an Operating signals, operating signal initially developed for commercial radiotelegraphy, radiotelegraph communication and later adopted b ...
s are used in conjunction with APRS text messages to implement APRS calling. APRS calling is intended to complement monitoring voice calling frequencies.
Procedure
#The calling station sends a QSX signal to the station or group they wish to reach using an APRS text message. The QSX should include the necessary information for contact, possibly including frequency and mode.
#Once the called station or stations are ready to communicate on the specified channel, they answer using a QSX text message on APRS.
#The stations shift communications to the arranged channel.
Example
All APRS transmissions include the call sign programmed into the APRS unit. The text message doesn't necessarily require the station identification commonly seen in voice, CW or RTTY exchanges, so long as the programmed call sign is valid.
This example shows N6BRK announcing a net on 147.480 MHz to the NALCO APRS group. When ready to communicate on the coordinated frequency, KJ6VVJ responds with an acknowledgment to the QSX. If the operating mode isn't obvious in context of the frequency, the initiating stations QSX should specify what it is.
See also
*
ACP-131
ACP-131 is the controlling publication for the listing of and It is published and revised from time to time by the Combined Communications Electronics Board (CCEB) countries: Australia, New Zealand, Canada, United Kingdom, and United States. W ...
- Combined Communications-Electronics Board Communications Instructions / Operating Signals
*
Amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency radio spectrum, spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emer ...
References
*American Radio Relay League. ''Field Service Form FSD-218''. American Radio Relay League, 2004.
*Bass, Richard K. ''GMDSS A study guide for the Global Maritime Distress Safety System''. Tele-Technology, 2007.
*Brehaut, Denise. ''GMDSS A User's Handbook''. Bloomsbury Publishing Plc, 2009.
*Combined Communication Electronics Board (CCEB). ''Communications Instructions ACP 131 (F) Operating Signals''. Combined Communications-Electronics Board, 2006.
External links
Amateur Radio Universal Text Messaging/Contact InitiativeARRL Field Service Form FSD-218 (1/04)
{{Packet radio
Digital amateur radio
Brevity codes
Packet radio