Specifications

20
a conventional Vee antenna as an inverted Vee. The coupler is very flexible
in this regard.
44..11 AAnntteennnnaa SSeelleeccttiioonn
The automatic antenna tuner will operate into almost any end fed antenna
with a length of 2.5 meters or more, provided an effective ground is used.
The antenna efficiency will be proportional to length and in most applica-
tions will be maximum at a length of 1/4 wavelength. This means that the
longest possible antenna should be selected for each installation.
Very short antennas are only recommended when there is no other alterna-
tive such as in a vehicular mobile installation. The performance of short
whip antennas is usually very poor, particularly at the lower frequencies,
and radiation efficiency will be only a few percent of a full sized antenna.
However, a special electrically long antenna such as the SG-303 9 ft. mobile
antenna overcomes much of the radiation problem.
44..22 WWhhiipp AAnntteennnnaass -- 22..55--33..00 mmeetteerrss ((88--99 fftt))
This antenna is recommended only for vehicular mobile installations. The
short length will result in poorer performance when compared with the
longer antennas. A special high performance 9 foot antenna, the SG-303, is
manufactured by SGC specifically for this problem. The SG-303 is SGC Part
Number 55-27.
44..33 WWhhiipp AAnntteennnnaa -- 77..00 ttoo 88..55 MMeetteerr ((2288 fftt))
This antenna is recommended for marine installation on smaller vessels. It
may also be used in base stations if there is no way of using a longer anten-
na. The SG-203 is this type of antenna. Order SGC Part Number 55-23.
44..55 LLoonnggwwiirree AAnntteennnnaa --
2233 mmeetteerr ((7755 fftt)) aanndd 4466 mmeetteerr ((115500 fftt))
For most applications the longwire antenna will give the best results and is
recommended when practical. The diagrams at the end of this section show
some recommended methods of installation. These are only a few of the
many possible methods of installation and frequently a different configura-
tion will be the best at a particular site. SGC's long wire antenna, 60 feet in
length, provides efficient operation on low frequencies and high frequen-
cies alike. Order SGC Part Number 55-10.
SGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA 98005 USA
P.O. Box 3526, 98009 Fax: [phone] Tel: [phone] or 1-800-259 7331
E-mail: [e-mail] Web site: http://www.sgcworld.com
© 1998 SGC Inc
SG-235 Manual