{{Unreferenced, date=December 2009
A ramark, acronym for radar marker, was a type of
radar beacon
Radar beacon (short: racon) is – according to ''article 1.103'' of the International Telecommunication Union's (ITU) ITU Radio Regulations (RR) – defined as "A transmitter-receiver associated with a fixed navigational mark which, when trig ...
used to mark maritime
navigation
Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, ...
al hazards. Ramarks are no longer in use.
They were wide-band beacons which transmitted either continuously or periodically on the
radar
Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, w ...
bands. The transmission formed a line of
Morse
Morse may refer to:
People
* Morse (surname)
* Morse Goodman (1917-1993), Anglican Bishop of Calgary, Canada
* Morse Robb (1902–1992), Canadian inventor and entrepreneur
Geography Antarctica
* Cape Morse, Wilkes Land
* Mount Morse, Churchi ...
characters on a
plan position indicator
A plan position indicator (PPI) is a type of radar display that represents the radar antenna in the center of the display, with the distance from it and height above ground drawn as concentric circles. As the radar antenna rotates, a radial tra ...
(PPI) radar display which radiated from the centre of the display to its edge, hence giving only a bearing, as opposed to
radar beacon
Radar beacon (short: racon) is – according to ''article 1.103'' of the International Telecommunication Union's (ITU) ITU Radio Regulations (RR) – defined as "A transmitter-receiver associated with a fixed navigational mark which, when trig ...
(racons) which give bearing and position.
Periodic transmissions every few seconds are usually used so that important radar targets behind the ramark beacon are not masked by the Morse characters. Ramark beacons are less commonly used than racons which give the location as well as the bearing of the hazard and do not clutter the display so much.
Navigational aids
Radar
de:Radar Beacon#Ramark