User's Manual Part 2

39
The NAV-7 is not receiving
1 Are you within range of a NAVTEX transmitting station?
2 Has there been a scheduled transmission since the NAV-7
was first switched on?
3 Check that the antenna is clear of obstructions and has not
suffered external damage
4 Check that the antenna cable is not damaged
5 Check that the antenna fault icon is not being displayed on
the status bar at the top of the display
6 From within the setup screens, check that the NAVTEX
transmitting stations and message categories are correctly
selected and that they have not all been disabled
7 From the Setup mode: receiver options screen
check that there isn’t a strong local interfering signal
8 Please contact your service agent
Software upgrade
From time to time software upgrades may be available. Check our website for
information on new releases.
External receiver
The NAV-7 has the capability to receive from an external receiver (not supplied) on
an additional NAVTEX frequency should such an additional frequency be mandated
by the IMO in the future.
NAVTEX messages from the external receiver appear on the View EXTERNAL
RECEIVER page.
The external NAVTEX data must be presented as a stream of NMEA NRX
sentences as defined in Annex C of the IEC61097-6 Ed.2 (2005) specification.
The external receiver may be another NAV-7; in such a case, a single antenna may
serve several displays. For more information, contact McMurdo Customer Service.