User's Manual Part 2

38
TROUBLESHOOTING GUIDE
General Points to Check
• Make sure that the antenna is mounted vertically, and is sited clear of
obstructions
• Make sure the vessel is operating within the coverage area of a NAVTEX
transmitter
• When the NAVTEX station(s) selected are transmitting, icons for 490, 518
and 4209.5 kHz show whenever a NAVTEX signal is received
• Ensure that the required NAVTEX station and message categories have not
been deselected in the NAV-7 setup menu
Antenna fault icon appears at the top of the display: active antenna
1 Turn off the NAV-7
2 Disconnect the active antenna and check that there is not a
short across the antenna’s TNC connector
3 Turn on the NAV-7, apply a 120 ohm 5 W resistor across the
TNC connector. If there is 12 V DC across the TNC then
either the antenna or coax cable is faulty
4 If there is not 12 V DC across the TNC connector then check
that Antenna power : Enabled is selected in the setup
screens
5 If these instructions do not work then please contact your
service agent
Antenna fault icon appears at the top of the display: passive antenna
1 Turn off the NAV-7
2 Disconnect the passive antenna and check that there is not a
short across the antenna TNC connector
3 Check that Antenna power : Disabled is selected in
the setup screens
4 If these instructions do not work then please contact your
service agent