NAVTEX (NAVigational TEXt Messages) is an information service which has been introduced by the IMO for commercial shipping and has passed a functional test for the first time in 1977 in Sweden.
Already in 1979, NAVTEX was the first NAVTEX transmitter network put into operation by the Baltic Sea states and with Resolution A.617 (15) already part of the GMDSS (Global Maritime Distress and Safety System). Since 1993, Navtex receivers have been mandatory on all ships over 300 tons GT and on passenger ships. Via SITOR B, clear text messages are transmitted on medium wave (either in English on 518 kHz or in country language on 490 kHz) navigation and weather messages are broadcast every 4 hours. For the messages in Japanese and Chinese language there are national special frequencies (424kHz and 486kHz) in these countries.
The NAVTEX messages contain all information relevant for navigation and are received free of charge by the recreational shipping industry!
Worldwide NAV Areas for NAVTEX reception
There are 21 NAV areas available worldwide today the range of the transmitting stations can be 100 – 600 nautical miles, depending on the station density. The individual stations in a lake area (NAV area) transmit with a time delay so that there is no mutual interference. Of course, modern NAVTEX units are connected to GPS and on-board instruments and thus automatically select the appropriate transmitting stations for the current cruising area.
NAV-Area III for the entire Mediterranean Sea with the Black Sea.
Here you can see a Navtex message from April 1 at 18:40 from the broadcast station Split for the Adriatic Sea in English:
011840 UTC APR
SPLITRADIO SHIPPING FCST FOR ADRIATIC AT 1800 UTC
WNG: POSSIBLE FOG AND VSBY LESS THAN 1 KM ON NORTH AND
ON THE OPEN OF CENTRAL ADRIATIC.
SYNOPSIS: FIELD OF ELEVATED AND LEVULLED AIR PRES OVER ADRIATIC
24 HRS OUTLOOK: CALM OR NE, ON THE OPEN NW WINDS 4-8, TOMORROW
W/SW 4-10 KTS. SEA CALM, TOMORROW CALM/SMOOTH. VSBY 10-20, ON
NORTH AND ON THE OPEN OF CENTRAL ADRIATIC LOCALLY REDUCED 1-4
DUE TO MIST, OVERNIGHT AND TOMORROW MORNING POSSIBLE FOG AND
VSBY LESS THAN 1 KM. ON NORTH/PARTLY CENTRAL ADRIATIC MOD CLOUDY,
ON REST PART MOSTLY CLEAR. NO TEMP CHANGES.
Additional features of good NAVTEX instruments
The logbook function available on good instruments can record the data from the instruments connected (via NMEA0183), including position, date and time, at a defined rate, thus writing a VERY accurate logbook. A special feature of the NAVTEX from ICS is the built-in barograph with calculation of the expected wind speed from the air pressure change.
In summary, although NAVTEX has been on the market for many years, it has lost none of its usefulness. The systems are inexpensive to purchase, easy to install, and work independently of any cellular network. The barograph function with storm warning underlines this even more.
Information and advice
For more information about Navtex, please contact WERNER OBER GmbH & Co KG – Yacht Electronics in person or by email.
Werner Ober GmbH & Co KG
6890 Lustenau | Austria