User's Manual Part 2

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Antenna
In any radio system an effective antenna installation is essential. Because of the
need to reduce the size of HF antennas so that they can be fitted to a vehicle,
mobile antenna bandwidth becomes quite narrow and hence tuning is critical. In
most cases the only tuning adjustment that can be effected is adjustment to
position. Particular attention must be given to the antenna position if satisfactory
performance is to be obtained. Refer to the instructions supplied with the antenna
you have selected.
Antenna Mounting
The antenna mounting must provide a strong secure anchorage for the base of the
antenna. To obtain maximum radiation, the antenna base must be well bonded
electrically to the vehicle chassis. Paint, dirt, rust, etc. should be removed from the
respective fixing points. The mounting point must provide a low resistance
electrical path to the main vehicle metallic structure.
Antenna Feed Cables
Antenna feed cables should be run (as far as possible) away from other vehicle
wiring and especially away from ignition high tension wiring. Where passing
through body panels or internal bulkheads, grommets must be used to protect the
cables. Water-proof connectors must be used when they are outside the vehicle.
Voltage Standing Wave Ratio (VSWR)
After installation it is recommended that the VSWR of the antenna should be
measured for each channel. The instructions supplied with the antenna selected
will detail this operation.