18
Installing the Radio
TM9100 Installation Guide
© Tait Electronics Limited
August 2005
2.4
Installing the Antenna
This section provides information on installing an external antenna within
the RF exposure limits.
Install the external antenna according to the antenna manufacturer’s
instructions. Good quality 50
Ω
coaxial cable must be used, such as RG58
or UR76.
Important
Route the cable in a manner that minimizes:
■
coupling into the electronic control systems of
the vehicle
■
coupling of electric vehicle systems, such as alternators,
into the radio.
Avoid sharp bends in the cable. These distort the cable and
alter its electrical characteristics.
Warning!!
RF exposure hazard
To comply with FCC RF exposure limits:
1.
Mount the antenna at a location such that no person or persons can
come closer than 35 inches (0.9 m) to the antenna.
2.
For 40W/50 W radios:
■
VHF radios must be installed using an antenna mounted centrally
on the vehicle roof, with a gain of 2.15dBi or 5.15 dBi.
■
UHF radios must be installed using an antenna mounted either
centrally on the roof with a gain of 2.15 dBi or 5.65 dBi, or
centrally mounted on the trunk with a gain of 5.65dBi.
3.
For 25W radios, the radio must be installed using an externally
mounted antenna with a gain of either 2.15 dBi or 5.15dBi.
Terminating the
Antenna Cable
1.
Run the free end of the coaxial cable to the radio’s mounting position
and cut it to length, allowing approximately 8 inches (20 cm) excess
at the radio end.
2.
Terminate the free end of the antenna cable with the mini-UHF plug
or BNC plug (supplied) as shown in
Figure 2.4
.
Figure 2.4
Terminating the antenna cable
5/16"
9/16"
5/32"
(4 mm)
(8 mm)
(14 mm)
