Icom IC-756 Marine Radio User Manual


 
Unpacking
After unpacking, immediately report any damage to the
delivering carrier or dealer. Keep the shipping cartons.
For a description and a diagram of accessory equip-
ment included with the IC-756, see UNPACKING on
p. ii of this manual.
Selecting a location
Select a location for the transceiver that allows ade-
quate air circulation, free from extreme heat, cold, or
vibrations, and away from TV sets, TV antenna ele-
ments, radios and other electro-magnetic sources.
Grounding
To prevent electrical shock, television interference
(TVI), broadcast interference (BCI) and other prob-
lems, ground the transceiver through the GROUND ter-
minal on the rear panel.
For best results, connect a heavy gauge wire or strap
to a long earth-sunk copper rod. Make the distance be-
tween the GROUND terminal and ground as short as
possible.
R WARNING: NEVER connect the [GND]
terminal to a gas or electric pipe, since the connec-
tion could cause an explosion or electric shock.
OPERATING ANGLE ADJUSTMENT
Antenna
For radio communications, the antenna is of critical im-
portance, along with output power and sensitivity. Se-
lect antenna(s), such as a well-matched 50 antenna,
and feedline. 1.5:1 of Voltage Standing Wave Ratio
(VSWR) is recommended for a desired band. Of
course, the transmission line should be a coaxial cable.
When using 1 antenna, use the [ANT1] connector.
CAUTION: Protect your transceiver from lightning by
using a lightning arrestor.
13
2
INSTALLATION AND CONNECTIONS
PL-259 CONNECTOR INSTALLATION
30 mm
9
8 in 10 mm
3
8 in 12 mm
1
16 in
Antenna SWR
Each antenna is tuned for a specified frequency
range and SWR may be increased out-of-range.
When the SWR is higher than approx. 2.0:1, the
transceivers power drops to protect the nal transis-
tor. In this case, an antenna tuner is useful to match
the transceiver and antenna. Low SWR allows full
power for transmitting even when using the antenna
tuner. The IC-756 has an SWR meter to monitor the
antenna SWR continuously.
30 mm
10 mm (soft solder)
10 mm
12 mm
solder solder
Soft
solder
Coupling ring
Slide the coupling ring
down. Strip the cable
jacket and soft solder.
Slide the connector
body on and solder it.
Screw the coupling
ring onto the
connector body.
Strip the cable as
shown at left. Soft
solder the center con-
ductor.
q
w
e
r
The rubber feet on the
bottom of the trans-
ceiver provide two op-
erating angles.