SG-231 MANUAL
SGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA. 98005 USA
© 11/00 SGC, Inc.
P.O. Box 3526, 98009 Fax: (425) 746-6384 Tel: (425) 746-6310
E-Mail: [email protected] Website: www.sgcworld.com
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midpoint connector. Because the antenna system starts at the output of the
coupler, the antenna lead from the coupler to the hypothetical antenna is part
of the antenna system. Avoid having the led end wire touch any other metal
structure: it will capacitively short your antenna to ground.
8. The backstay of your mast is the
only
viable antenna on a sailboat. The SG-
231 coupler is specifically designed to be used for such applications.
9.
For vehicular installation, do not use any inexpensive CB antennas and/or
mounts. These antennas will not perform well from 1.8 to 10 MHz even though
the coupler will load and tune the antenna whip. A high voltage of 15,000 to
30,000 volts RF will be applied to the antenna depending on the RF power level
and frequency. The inexpensive ball mounts for CB antennas are not designed
for so stringent a purpose. We recommend the use of an antenna system such
as the SG-303: it was specifically designed for such extreme applications.
5.1 Steps to Antenna Installation
System installation is a three-part process covering the following steps:
1. Selection and installation of the antenna.
2. Mounting the antenna coupler.
3. Connecting the appropriate interface cables between the coupler and the
transceiver.
This manual section will discuss the three steps mentioned above in detail and will
provide sufficient information to enable the user to confidently install a complete
system properly.
The antenna system is a key part of the communication system. For satisfactory
operation the system must be carefully selected and then installed correctly. The
unbalanced antennas used with the automatic antenna coupler, use the ground
(counterpoise) as half of the antenna system. The ground forms an “image” antenna
and is a critical part of the system. It is essential to consider both the ground and the
antenna when designing the system installation.
5.2 Antenna Location
The figures in Section 4.0 illustrate several different antenna installations. The
following points should be carefully considered when designing the antenna system.
1. The antenna should be located in a position free of obstructions, particularly
in the desired direction of communication.
2. The antenna should be kept as far away as possible from buildings, trees,
and vegetation. If metallic masts or supports are used, arrange the insulators
so that the antenna is spaced at least 2 meters from the mast.