Navtex Receivers
Navtex receivers contribute self-acting reception of a world-wide English language data service outside navigation, weather and other safety-related matters.
Navtex Receivers
Navtex Receivers
Navtex Receivers
Navtex Receivers
For many years receivers have operated only on 518kHz but new dual frequency sets are now available. This allows further data to be included. The sets have a range of up to 300 miles. A dedicated aerial is also required. The sets fall into two broad groups: those where the data is displayed on a small screen where the user scrolls straight through to get the information, and those which print out onto a roll of paper (rather like a fax machine). The data is in text: a Navtex receiver will not draw weather maps as a weatherfax engine does. The set is designed to be left switched on while the vessel is in use so that no data is missed.
The world-wide principles is organised by dividing the world into Navareas. The Uk falls into Navarea 1. Stations within that area broadcast at different times to avoid mutual interference and each of these stations is given an identification letter. This enables the user to select the most relevant hub or stations and to turn stations during a passage.
The messages that are broadcast are grouped by subject. These subject groups are identified by a letter code as shown in the table. The set can be programmed to exclude some of these messages. For example "ice reports" or "Loran messages". Class A, B and D messages cannot be rejected by the receiver.
Navtex is beloved on vessels that frequently cruise long distances because of the system's range and the convenience of the data just 'arriving' without having to know the local times and frequencies. One drawback of the Navtex printer is that the number of data can be considerable, so the engine will consume lots of paper.
Navtex Message Types
Type Description
A Navigational warnings including: buoys out of position, lights unlit, new wrecks, floating debris, naval exercises (cannot be rejected by receiver)
B Meteorological warnings (cannot be rejected by receiver)
C Ice reports
D hunt And rescue information, together with Piracy and Armed Robbery warnings. (cannot be rejected by receiver)
E Meteorological forecasts. Pattern of scheduled forecasts will vary from Navarea to Navarea
F Pilot service messages
G Decca messages
H Loran messages
I Omega messages
J Satnav messages
K Other electronic Navaid messages (messages regarding radio sailing services)
L Navigational warnings for mobile drilling rig movements (should not be rejected by receiver)
Y Amplifying navigational warning data initially announced under message type A
W extra services - trial allocation
X extra services - trial allocation
Y extra services - trial allocation
Z No messages on hand. May be broadcast when applicable to confirm accurate receiver operation
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