SG-303/307 WHIP ANTENNA MANUAL
© SGC 2007
INSTALLATION WITH AN ANTENNA COUPLER
The high voltage wire which connects the coupler to the antenna base must be at least 2 inches
away from any metal structure. Never tie wrap this wire to other wires or to a metal holder. If the
high voltage wire is not at least 2 inches away from any metal structure or wires, high voltage
arcing may occur, which will damage the coupler and subsequently the transmitter.
Mechanically the coupler can be installed in any position.
NOTE: Any excess high voltage wire between the antenna and the coupler must be
cut off before attaching the wire to the coupler. The ground wire should also be kept
as short as possible.
Coupler wiring through the body of the vehicle
IMPORTANT: The high voltage antenna wire must always be at least 2 inches away from any
metal structure.
The antenna must be unobstructed. Do not mount the antenna next to the metal body of the
vehicle. This will severely limit the radiation and the range of communication, and may cause the
antenna to arc and damage the coupler and transmitter.
The hole diameter for the high voltage and waterproof feed-through bushing is .890 inches. Install
the bushing in a location which allows the antenna to be lowered. Routing the RF coaxial cable
and the two wires for the 12 volt supply to the coupler is not critical. If necessary, the coupler can
be installed as much as 100 feet away from the radio. These wires can be tie wrapped to any
metallic or non-metallic point of the body structure.
