Mobile Radio Installation Guidelines

Transceiver Location
a.A transceiver location should be selected that provides a solid mounting point which does not interfere with the vehicle operator controls and provides adequate ventilation.
NOTE: Do not mount any transceiver, microphones, speakers, or any other item in the
deployment path of the airbag system.
b.Before using screws to mount the tranceiver equipment, be sure to check for vehicle wiring
under the carpet or behind the instrument panel which could be pinched, cut, or otherwise

Radio Wiring and Routing
a.Transceiver power connections should be made directly to the battery and appropriately
fused as close to the battery as possible. A weatherproof fuse holder is recommended. Twist
the positive and negative power leads together to enhance noise immunity.
b.Use caution when routing wires between the passenger and engine compartments to avoid
chafing or pinching of wires. Use grommets over any exposed sharp edges and strain reliefs
to keep wires in place. Seal all holes to prevent moisture intrusion.
c.Route and secure all underhood wiring away from mechanical hazards such as exhaust
manifolds and moving parts (steering shaft, throttle linkage, fans, etc.).
d.Maintain as great a distance as possible between mobile radio power leads and the vehicle’s
electronic modules and wiring. Avoid running power leads in parallel with vehicle wiring
over long distances.

Antenna Location and Installation
a.Permanently installed antennas are preferable over magnetic, glass, or body lip mounts for
anything other than for low power or temporary installations. Most of these alternate
antennas can reflect significant power back at the feedpoint; this reflected power could then
radiate from the feedline inside the passenger compartment and be picked up by the vehicle
wiring. However, a magnetic-mount antenna is a good tool for checking the proposed fixed
antenna location for unwanted effects on the vehicle since antenna location is a major factor
in these effects.
b.Glass mounted antennas should be kept as high as possible in the center of the rear window
or windshield. Some vehicles use glass that contains a thin metallic coating for defrosting
or to control solar gain; glass mount antennas may NOT function properly when mounted
on this type of glass. (Ford Privacy Glass contains such a coating.) Also, refer to the antenna
manufacturer’s recommendations.
NOTE: On some Ford vehicles, the rear window contains the entertainment radio
antennas (AM and FM). Avoid using the rear window to mount mobile radio
antennas in these vehicles.

If a magnetic mount antenna is used, take care to locate the magnetic base in a location which avoids interference to the vehicle’s compass mechanism, if so equipped. Also, some Ford
vehicles use non-metallic body panels (decklids, etc.). If metallic backing panels are used,
do not block the reception paths for factory installed antennas, such as Global Position
Satellite (GPS) transceivers, if so equipped.
d. Antenna Tuning: It is important that the antenna be tuned properly and reflected power be
kept to less than 10% (VSWR less than 2:1).
NOTE: Your installation should be checked periodically for proper SWR and any signs
of damage or deterioration to maintain proper operation with your vehicle.

Antenna Cable Routing
a.Always use a high quality, one piece coaxial cable (at least 95% shield coverage). Connector
quality and termination techniques are just as important. The ARRL handbook provides
excellent guidelines for terminating coaxial cables.
b.The antenna cable should be treated in the same way as the control and power cables. Avoid
sharp edges and pinches and keep the cable as short as possible. Also, avoid routing the
antenna cable in parallel with vehicle wiring over long distances. If it is necessary to cross
over wiring, cross at right angles. (In some cases, additional shielding between the antenna
cable and the vehicle wiring may be helpful.


This entry was posted in Uncategorized. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s