Roof Mount Antenna
C-4 <Italic>IxN2X Getting Started Guide, Release 7.50
C
impedance (low R and low L) ground system. We recommend that this ground be
interconnected to the tower ground and power ground to form one system.
The earth ground electrode should be driven in at least 8 ft. (2.44m) into the
earth. A #6 grounding wire should be used.
GPS Mast Location
Requirements
Preferred Location
The preferred mounting location for the GPS antenna is an unobstructed 360-
degree view of the sky above the horizon. The specific requirements are:
Requirements if Preferred Location is Not Available
If an unobstructed 360-degree view of the sky is not available then the following
requirements should be met:
Note: When attaching to the grounding stud (M8), use a maximum of
88.5 lbf-in. (10 N-m) of torque.
Table C-2. GPS Mast Preferred Location Requirements
1. Optimal view of the sky.
2. Not the highest point of the building so as to reduce the possibility of
lightning strikes.
3. Located at least 12 ft. from any large metal objects.
4. Located at least 10 ft. from any other GPS antenna.
5. Located within 30 ft. of where the coax cable enters the building.
6. The GPS antenna mast should be mounted at least 4 feet higher
than the highest horizontal reflective surface such as roof top
mounted AC units.
Table C-3. GPS Mast Location Requirements if a Preferred Location is not
Available
1. 300-degree azimuth view of the sky.
2. No vertical obstructions to obscure the view of the antenna from the
horizon for more than 10 degrees.
3. No high-power radar signal beamed directly at the unit; this may
damage the pre-amplifier in the antenna.
4. No harmonics from a high-power, broad band transmitter within a
few megahertz of the carrier frequency (1.575 GHz) should be
present. This may jam the GPS receiver.
