Installing The Antenna - NorthStar 961 Install Manual

Installing the antenna

Choosing an
antenna
Choosing an
antenna location
961/962 INSTALLATION MANUAL Revision A
The processor connectors are as follows:
•
power connector (3-wire)
•
TNC connector (control head #1)
•
TNC connector (control head #2)
•
interface connector P1 (18-wire)
•
interface connector P2 (18-wire)
•
GPS antenna connector (BNC)
•
DGPS beacon antenna connector (UHF)
• PC connectors (variable)
•
VGA video out (15-wire)
There are three antenna choices for the 961/962X and 961/962XD:
• for reception of GPS-only signals (the standard one-piece "active"
AN150 antenna)
•
for reception of both GPS and DGPS signals (a two-piece antenna
system comprising the standard AN150 GPS antenna and the 8410
DGPS coupler)
•
for reception of both GPS and DGPS signals (optional one-piece
AN205-P "combination" antenna)
Choosing the AN150 antenna location
The GPS receiving antenna is a vital link between the 961/962's receiver
and the outside world. Aesthetics and easy access should be secondary to
providing strong and reliable GPS signals to the 961/962. You should
select a location for the antenna that meets the following requirements:
•
The antenna should have a reasonably clear view of the horizon, but
be no higher than necessary, since side-to-side motion of the
antenna caused by rolling of the vessel may degrade SOG and COG
readings. The antenna should be 12 to 18 inches above the
surrounding surfaces to avoid interference.
• The antenna must be out of the radiation path of any on-board radar
sets or strong magnetic fields.
•
The antenna must be lower than any INMARSAT communications
antenna.
•
The antenna should be as far as possible from other high-power
transmitting antennas.
•
Watch out for electromagnetic "shading" of antennas from rigging,
other vessels, shoreline buildings, and so on. Secure the cable well.
To avoid mutual interference among different antennas on the vessel, see
the illustration of recommended separation distances in "Figure 5:
Separation distances between antennas" below. This figure shows the
SECTION TWO - Installation
Page 15