How to make navtex your friend for life

Shipaxis Technical Services

20 questions on Navtex

Do you struggle to sort out navtex warnings ? If yes, you are not alone

Navtex is as important equipment as any other equipment on the wheel house. But sometimes we tend to give Navtex a step motherly treatment by keeping it last in priority list. One reason for that is we are never sure how to handle Navtex.
If we know how it works and how best we can handle Navtex on board, handling Navtex messages will be as easy as eating a pie of cake.1. What is the source of Navtex messagesNavtex station receives these messages from navtex coordinator who in turn receives these messages from various sources. These sources include Meteorological office, Hyrdrographic office or rescue coordination centers (RCC).
Navtex station

What is the difference between service area and range of the Navtex station ?

A navtex station have a pre-defined area for which it is responsible for sending information. This is called service area of navtex station. The Navtex coordinator of the country decides the service area for the navtex station when it is being set up initially.
If it does not overlap the service area of a navtex station of another adjoining country, usually there is no issue for the navtex coordinator to set up service area.
But if case any dispute over setting up the service area for a navtex station, IMO navtex coordination panel helps in setting this up.
Service area and range of navtex
the range of transmitter of the navtex station need to be sufficient to cover its service area. In fact it need to be more than the service area of the navtex station. This way the ship’s proceeding from outside the service area can receive the navtex messages before entering the service area.
How to know which navtex station will be in range on my passage ?Same like above, We can find this information in the ALRS or ADRS 1,3,4,5.  Just open ADRS Vol 1,3,4,5 on your dedicated computer and make sure Navtex is selected from “View” option.This will give you all the navtex stations which you can zoom the map to view a particular one you might be looking for. Otherwise you can choose the area (or country) from the geographical area selection panel from left menu bar.
Navtex station limits
How does navtex station sends navtex messages
The Navtex station sends these message on a designated frequency and we receive it on board if we are in range of that navtex station.If you have a thing for numbers, then here are few numbers you may wish to knowNavtex uses frequency 518 KHz for transmitting messages in english.Navtex uses another frequency 490 kHz for transmitting messages in local language.
Latest regulations require that Navtex messages be sent on one HF frequency also either 4mHz or 8 mHzThe range of the navtex transmission is between 250NM to 400NM. for MF broad casting

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