User Manual

14221-1200-4000, Rev. A
35
6.1.1 Direct Center or Center-Rear of Rooftop
The center of the vehicle’s roof is the best location for a rooftop-mount antenna (location  in Figure
6-1). For optimal performance, the mounting area under the antenna must be flat with a minimum radius
of six (6) inches of metal ground plane. It must be located directly in the center of the roof to minimize
human exposure to RF electromagnetic energy. Other obstructions such as a light bar or another antenna
may prevent the antenna from being mounted in the direct center of the roof. In this case, the antenna
should be mounted a minimum of one foot away from and behind the obstruction but in the middle of the
roof with respect to the left and right sides of the vehicle (location  in Figure 6-1).
6.1.2 Center of Trunk Lid
Certain vehicles do not allow for the antenna to be placed in the center or center-rear of the roof. In this
case, the next best location for the antenna is in the direct center of the trunk lid (location  in Figure
6-1). The antenna must be located directly in the center of the trunk lid to minimize human exposure to
RF electromagnetic energy.
6.1.3 Rear Deck Lid for Stand-Alone GPS Receive Antenna
If a GPS combination-type antenna is not utilized for the mobile radio installation and the radio’s GPS
receiver functions must be available for operational use, a stand-alone GPS receive antenna must be
separately mounted and connected to the radio. The vehicle’s rear deck lid (location  in Figure 6-1) is
the recommended mounting location for this case. This locates the GPS antenna inside the vehicle.
6.2 ANTENNA INSTALLATION PROCEDURES
An antenna must be installed before completing the radio installation.
Table 4-7 (page 30) and Figure 6-1 list the mobile radio antennas available for use with the radio. As
presented in the previous section, various mounting locations exist. Optimal performance is achieved via
a rooftop antenna mounted in the direct center of the motor vehicle’s roof.
6.2.1 Installing Antenna Mounts AN-125001 -002 and -004
These NMO style antenna mounts can each be used with several different antenna elements. Only limited
access under the mounting location is typically required. The installation procedure is presented in
Section 6.2.1.3.
6.2.1.1 Standard Antenna Mount AN-125001-002
This standard ¾-inch NMO antenna mount requires a ¾-inch hole in a relatively flat area of the vehicle
body, with a vehicle metal thickness of between 0.020 and 0.040 inches.
6.2.1.2 Thick-Roof Antenna Mount AN-125001-004
This thick-roof NMO antenna mount uses either a ⅜ -inch or a ¾-inch mounting hole in a relatively flat
area of the vehicle body, with a vehicle metal thickness of between 0.040 and 0.1875 inches (
3
/
16
-inch
maximum thickness).
NOTE