only on certain frequencies? Does the problem only happen in certain
modes? This type of information is extremely useful in quickly isolating
your problem.
B
B e
e p
p a
a tt ii e
e n
n tt
Finding the reason for less than ideal system operation may
take one telephone call or it may take several calls. Regardless of how com-
plex the problem is, your SGC representative will be able to walk you
through the process of solving your problem in a logical step-by-step man-
ner. There is nothing magic about HF. Although it may seem so at times, the
rules of physics don't change. The Smartuner and accessories will always
give top performance when carefully installed.
4
4..0
0
A
An
ntte
en
nn
na
a T
Ty
yp
pe
es
s
The automatic antenna tuner is designed for use with end-fed unbalanced
antennas such as whips and long wires. The radiating portion of the anten-
na is connected directly to the tuner through a high voltage insulator. It is
extremely important that the antenna type, site location and grounding
technique be correctly chosen so that the system will radiate effectively.
Broadband resonant antennas (e.g. log periodic) that cover the full range of
the system may be used with the tuner if desired. Narrow band resonant
antennas, such as dipoles, vee's and inverted vee's may only be used if the
antenna VSWR (including coaxial feeder) is less than, or equal to 3:1 at the
operating frequency.
Note that if a dipole or Vee type antenna; is used, the antenna may be oper-
ated at any frequency within the range of the coupler if each side of the vee
or dipole is 23 feet or longer. In addition, the SG-230 is just as happy feeding
a conventional Vee antenna as an inverted Vee. The coupler is very flexible
in this regard.
4
4..1
1
A
An
ntte
en
nn
na
a S
Se
elle
ec
cttiio
on
n
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,
19
© 1998 SGC Inc
SG-230 Manual
SGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA 98005 USA
P.O. Box 3526, 98009 Fax: 425-746-6384 Tel: 425- 746-6310 or 1-800-259 7331
E-mail: [email protected] Web site: http://www.sgcworld.com