Seamarks/Radar Beacons

Seamark tagging

Radar beacons

The tags defined on this page will render in various nautical charts.

This page defines values for the "seamark:radar_transponder:category" tags and other attributes applied to fog signals.

Type	S100 code	seamark:type	Definition	Rendering
Radar transponder beacon	RTPBCN	radar_transponder	A transponder beacon transmitting a coded signal on radar frequency, permitting an interrogating craft to determine the bearing and range of the transponder.

Attribute	seamark:radar_transponder:<attribute>	Value type	Definition
Value of maximum range (VALMXR)	range	Decimal	The maximum range at which the signal can be detected in nautical miles.
Radar wave length (RADWAL)	wavelength	Text	The distance between two successive peaks (or other points of identical phase) on an electromagnetic wave in the radar band of the electromagnetic spectrum.
Signal group (SIGGRP)	group	Text	The number of signals, the combination of signals or the morse character(s) within one period of full sequence.
Signal sequence (SIGSEQ)	sequence	Text	The sequence of times occupied by intervals of signal on and signal off.
Signal period (SIGPER)	period	Decimal	Time of the time occupied by an entire cycle of intervals of signals on and signals off.
Sector limit one (SECTR1)	sector_start	Decimal	The sector limit 1 specifies the first limit of the sector. The order of sector limit 1 and sector limit 2 is clockwise around the central object.
Sector limit two (SECTR2)	sector_end	Decimal	The sector limit 2 specifies the second limit of the sector. The order of sector limit 1 and sector limit 2 is clockwise around the central object.

S-101 ENC/iENC registry (iho.int), the ENC Data Classification and Encoding Guide (DCEG) can be downloaded as zipped PDF, online access to symbols in Portrayal Register
International nautical chart symbol legend (Chart INT-1, NOAA)
Encoding Guide for Inland ENCs (openecdis.org, 2018), an international standard of the Inland ENC Harmonization Group is currently in development (IEHG Publication S-401, 2019)
European Code for Inland Waterways (CEVNI), (UNECE, Fifth revised version 2015)
European Code for Signs and Signals on Inland Waterways (SIGNI), (UNECE Resolution N0. 90, 2018)
U.S. Aids to Navigation System – also details the Western Waters Marking System, Intracoastal Waterway system, and Uniform State Waterway Marking System

Category (CATRTB)	seamark:radar_transponder:category	Definition
Ramark	ramark	A radar marker beacon which continuously transmits a signal appearing as a radial line on a radar screen, the line indicating the direction of the beacon.
Racon	racon	a radar beacon which returns a coded signal which provides identification of the beacon, as well as range and bearing. The range and bearing are indicated by the location of the first character received on the radar screen.
Leading racon/radar transponder beacon	leading	A radar beacon that may be used (in conjunction with at least one other radar beacon) to indicate a leading line.