NorthStar Navigation VHF Marine Radio Explorer 721US - Manual (Page 41)

41 Northstar Explorer VHF Series: 721US, 721EU Operation and Installation Manual
Appendix B - Troubleshooting
1. The transceiver will not power up.
A fuse may have blown OR there is no voltage getting to the transceiver.
a) Check the power cable for cuts, breaks, or squashed sections.
b) After checking the wiring, replace the 7 Amp fuse (a spare fuse is supplied).
c) Check the battery voltage. This must be greater than 10.5 V.
2. The transceiver blows the fuse when the power is switched on.
The power wires may have been reversed.
a) Check that the red wire is connected to the positive battery terminal, and the black wire is connected
to the negative battery terminal.
3. The speaker makes popping or whining noises when the engine is running.
Electrical noise may be interfering with the transceiver.
a) Re-route the power cables away from the engine.
b) Add a noise suppressor to the power cable.
c) Use resistive spark plug wires and/or use an alternator whine fi lter.
4. No sound from the external speaker.
a) Check that the external speaker cable is physically connected.
b) Check the soldering of the external speaker cable.
5. Transmissions are always on low power, even when high (HI) power is selected.
The antenna may be faulty.
a) Test the transceiver with a diff erent antenna.
b) Have the antenna checked out.
6. Battery symbol is displayed.
The power supply is too low.
a) Check the battery voltage. This should be at least 10.5 V ± 0.5 V DC.
b) Check the alternator on the vessel.
7. No position information is displayed.
The GPS cable may faulty or the GPS setting may be incorrect.
a) Check that the GPS cable is physically connected.
b) Check the polarity of the GPS cable.
c) Check the baud rate setting of the GPS if applicable. The baud rate setting should be 4800 for NMEA
or 38400 for NAVBUS. Parity should be set to NONE.