June, 2000
6880907Z66-O
2-1
Section 2
Installation
Your mobile two-way radio offers various installation
possibilities. The standard radio package contains a
direct mounting trunnion and power cables. Ensure
that the cables can be routed to the radio without being
exposed to excessive heat or mechanical damage.
Before You Start
Licensing
For the United States only: The Federal Communica-
tions Commision (FCC) regulations state that a station
license must be obtained for each radio installation by
the owner of the equipment. The station licensee is
responsible for ensuring the transmitter power, fre-
quency, and deviation are within the limits permitted
under the station license. For outside the United States:
Adhere to the applicable rules of your local licensing
authority.
Your radio is completely adjusted, tested, and
inspected before shipment. No technician's license is
required for installing and maintaining radio equip-
ment. However, the frequency and deviation of the
transmitter must be checked at the time of installation
and at least annually.
Power Protection Circuitry
The GTX mobile you are installing has been tested for
proper transmitter power output before leaving the
factory. Each radio is set to the proper output power
level while connected to an accurate 50 Ohm load
impedance. Once the power level has been set, the
internal power control/protection circuitry will reduce
the power output whenever it senses a load impedance
significantly different from 50 Ohm. This protection
circuitry greatly enhances the radio's reliability with
minimal performance degradation.
If you check transmitter output power levels during
installation, be sure you are using a good 50 Ohm load,
with a minimum of adapters and using short test
cables. Any load variation from 50 Ohm may cause an
apparent reduction in output power due to the normal
operation of the control/protection circuitry. A load
impedance of 50 Ohm is required for all bands. How-
ever, it has more effect in 800/900 MHz radios since
cables, meters, connectors, etc. have larger effects in
these bands. If power seems to be unusually low
(greater than can be explained by the normal calibra-
tion differences you experience), check your test setup.
If power output goes up as you improve the quality of
the load impedance (be sure to de-key when making
any changes in load), the control/protection circuitry is
performing normally.
Typical mismatches in the load impedance (greater
than 1.2:1 VSWR) may result in a 10-20% variation in
the actual measured power output. Within these limits,
the radio operates normally and you should not
attempt to service it.
Installation Planning
Planning
Planning is the key to fast, easy radio installation.
Before a hole is drilled or a wire is run, inspect the vehi-
cle and determine how and where you intend to mount
the antenna, radio, and accessories. Plan wire and cable
runs to provide maximum protection from pinching,
crushing, and overheating.
Recommended Tools For Installation
The following tools are recommended for proper
installation of your new radio.
• Portable Drill
• Hammer
• Center Punch
• 5/ 16" (8 mm) Hex Nut Driver
• 1 /4" (7 mm) Hex Nut Driver
• Phillips #2 Screwdriver
• TORX Screwdriver, T25
• 3/8" (9 mm) Diameter Drill Bit
• 5/16" (8 mm) Diameter Drill Bit
• 5/32" (4 mm) Diameter Drill Bit
Antenna Mounting
Refer to Section 1 of this manual in subsection “Mobile
Antenna Installation” on pages 1-2 and 1-3.
