INTRODUCTION
The Clipper Easy-Navtex is a dual frequency navtex receiver allowing
reception of either the navtex national (490kHz) service or the
international (518kHz) service. Facilities are provided to program the
receiver for both stations and messages on each of the two frequencies.
The receiver is simple to use with all instructions clearly displayed on
the screen.
A compact stubby antenna is supplied with the receiver.
Whilst the receiver is designed to operate from the vessel’s 12 volt
system, it can be powered by domestic mains using a regulated 12
volt power supply ( not a battery charger). A custom power supply is
available from Nasa Marine spares department. When used in a
domestic environment it is important that the negative supply wire is
connected to a good ground (e.g. mains ground or a suitable water
pipe) to avoid interference.
INSTALLING THE ANTENNA
Owing to the low frequency nature of the signal, it is not necessary
to mount the antenna at a great height. However many types of
electrical apparatus emit interference and it is important that the
antenna is well clear of such interference. Troublesome items are
alternators, ignition coils, motors, strip lights, inverters etc. Select a
position as far from likely sources of interference as is practical
and mount the aerial using the flange on the base. Ensure that the
antenna is at least 30cms from other metal structures that are
parallel to it.
A pushpit mounting bracket is available from Nasa Marine spares
department. The bracket permits the antenna
to be mounted to any 25mm diameter horizontal rail.
Run the antenna lead back to the receiver. The cable can be
shortened or lengthened using standard 75 ohm coaxial cable.
Take great care when making connections. Power for the
active antenna is supplied by the coax so all joints should be
soldered and properly insulated. Alternatively a 7 metre
extension cable is available from your chandler, or Nasa
Marine spares department.
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