Midland ALAN 199-A, User Manual

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• Mount it as far as possible from sources of noise (ignition system, gauges, etc.)
and keep the transmission line away from these noise sources.
• An antenna mounted in a boat requires a good ground connection.
This can be either a metal hull or a ground made of tin-foil or copper sheeting.
This ground should cover an area of at least 1 m2 or more. Be sure the transceiver
also has an adequate ground. There are many types of mobile CB antennas: a full
quarter-wave length whip, a centerloaded whip, top loaded whip and the base loa-
ded type are typical. A vertically polarized whip antenna is best suited for mobile ser-
vice. It is omnidirectional.
If it’s the loaded type, you will find it a physically shorter antenna. But, for greater
efficiency the 2.5 m long, full quarter-wave whip is better. Antenna length is directly
related to efficiency.
Generally, the longer it is the more efficient.
There are many possible antenna locations on a car.
Four of the most popular are shown and discussed on the following.
Roof Mount
In this position the antenna radiates equally in all directions.
Since the normal 1/2 wavelength whip antenna is too long for
roof mounting on a vehicle, the antenna is shortened and loa-
ding coil is used to provide the proper electrical length. Our
fiberglass roof mount is a good durable antenna.
Front Cowl Mount The radiation pattern is slightly greater in the direction of the
rear fender opposite the side on which the antenna is moun-
ted. However, the front position offers a number of advanta-
ges. The CB antenna can be easily mounted. It can double as
both the CB and the standard auto radio antenna by emplo-
ying a two-way coupler. Ask about our complete line of
antennas.
Rear Deck Mount The radiation pattern is stronger in the direction of the front
fender opposite the side on which the antenna is mounted. In
this position you can use a full quarter-wave antenna or a
shorter loaded whip. Here you might consider one of the full
2.5 meters whips.
Bumper Mount The antenna radiates in a pattern directly in front of and to
the rear of the vehicle, with maximum radiation directly away
from the vehicle, in a horizontal plane. Despite its fairly irre-
gular pattern, a bumpermounted full-length whip antenna
will normally give the best results. Removing the antenna is
simple and will leave no holes in the car.
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ISTR.199-A 3-12-2002 14:24 Pagina 5