Specifications

SMARTUNER MANUAL 33
SGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA. 98005 USA
© Nov2000 SGC, Inc. P.O. Box 3526, 98009 Fax: [phone] Tel: [phone]
E-Mail: [e-mail] Web Site: www.sgcworld.com
may be approximated by placing a screen of chicken mesh, copper hardware cloth, or
similar material over the roof of the building. More frequently, a counterpoise system of
radial wires must be used. SGC recommends the use of at least 8 to 12 radials bonded
together in the center. If the antenna is at ground level, the radials should be buried a
few inches below the surface.
5.4 Corrosion
Ground connections are subject to corrosion and oxidation. All joints must be clean and
the hardware adequately tightened. Joints should be well soldered wherever possible.
The joints may be protected by an application of silicon grease and, under severe
conditions, covered with electrical tape and waterproof varnish or a durable brand of
silicon caulking.
If you are mounting your SMARTUNER on a vessel where a lot of salt spray is en-
countered, it is a good idea to put the wire connections that are exposed to weather on
your six-month periodic maintenance plan. Then, every six months, you will be
reminded to undo each of the connections, clean, retighten, and reseal.
Use jumpers around metal backstay triangles on split backstay antennas. Corrosion may
cause up to several hundred ohms of resistance to occur even though you may think
that a metal-to-metal connection would be a good one.
5.5 Antenna Coupler Mounting
The coupler is mounted using the proper mounting ears on the case. Choose a location
immediately adjacent to the antenna feed point. In trunk-mounted mobile installations,
locate the coupler so that the antenna insulator is within a few centimeters of the
antenna exit hole. Note also that the antenna lead must pass through an insulated
bushing. High voltage connecting cable must be used. (RG-8U cable with solid
insulation may be used if the outer shielding is removed). When the coupler is installed
on the outside, or on the deck, we recommend a protective housing.
5.6 Antenna Connection
The antenna lead is connected to the high voltage insulator. During operation, use two
wrenches when tightening the nut to prevent the stud rotating. A potential of several
thousand volts may be present at the antenna terminal and adequate protection must be
made against accidental contact. It is also necessary that the antenna be spaced at least 3
centimeters from the conducting surface. Sharp points in the lead-in wire should be
avoided to prevent corona discharges.
6.0 Installation Procedures