iCOM AH-760 HF Automatic Tuning Antenna User Guide
- June 11, 2024
- ICOM
Table of Contents
iCOM AH-760 HF Automatic Tuning Antenna User Guide
IMPORTANT!
The antenna is a critical element in any communication system. Correct
installation is very important factor for achieving the utmost in antenna
system performance and operation of your transceiver. We recommend that
installation of the AH-760 HF AUTOMATIC TUNING ANTENNA be carried out by
qualified technicians only.
PRECAUTIONS
DANGER HIGH VOLTAGE! NEVER touch the antenna terminal, ground terminal or antenna while transmitting. Place the AH-760 in a position where no one can touch them.
NEVER use the antenna system without a ground connection. USE the ground terminals for the ground connection. The mounting plate is not internally connected. DO NOT operate your HF transceiver without running the vehicle’s engine. When the transceiver’s power is ON and your vehicle’s engine is OFF, the vehicle’s battery will soon become exhausted. DO NOT use the AH-760 in areas where the temperature is below –30°C or above +60°C.
FOR TRAFFIC SAFETY
Use the original Antenna Mounting Systems, which cover most of installations
scenarios on virtually any type of vehicle to ensure the best communications
and compliance with traffic safety guidelines.
INSTALLATION
Select or fabricate a strong metal bracket for the antenna plate, about 8–10 mm (0.31–0.39 inches) thick, and weld or bolt it firmly to the vehicle chassis or other strong structure. For the greatest radiation effectiveness, position antenna as high as possible. For human safety, mount the antenna at the front and opposite side of the steering wheel, whenever possible. Refer to the pictorial installations and scenarios shown in the overleaf. Make sure to allow enough clearance around antenna so that any antenna flexing will not damage the vehicle — bear in mind that Main Assembly can flex as much as 16 cm (0.63 inches), without damage. Make sure the upper 2/3rds of the antenna Main Assembly is as far from the vehicle’s vertical and horizontal metal panels as possible. Use the antenna Level Mark for reference. Mount the antenna on the bracket plate provided with a 17 mm (0.67 inches) hole for the M16×2 mm (M0.63×0.08 inches) threaded mounting stud. Rotate the Main Assembly until VENT and EARTH STRAP are directed towards the vehicle body, and then firmly tighten the stud nut. Use only the original hardware and proper tools.
RF-GROUND:
It is absolutely essential that the antenna is connected to an effective and
stabile RF GROUND POINT — the vehicle chassis. It is further recommended that
body panels are also bonded to the vehicle chassis. Make sure all contact
points are free of paint and ground to a shiny finish and protected from
rusting with conductive grease, before bolting the mounting stud and ground
strap terminals.
CABLING:
Three cables are supplied with each antenna — a coaxial cable, a control cable
and an adapter cable. A ground strap is provided on the base of the antenna to
ensure a reliable connection with the vehicle’s metalwork. Connect the ground
strap to both the chassis frame and the cabin metalwork, whenever possible.
Avoid feeding the antenna cables together with the engine ignition cabling
routes. Use a ground terminal for the entire HF system where your transceiver
is installed. Feed both (B+ and B–) thick wires from the vehicle battery to
the R/T location. Do not use the vehicle’s metalwork as a replacement of the
B– wire. Refer to typical correct installation cabling diagram for the
location of antenna cables and connection points.
D Typical Installation Scenarios for AH-760 HF AUTOMATIC TUNING ANTENNA
Most recommended SUV installation scenarios use a Universal Gibbet Mounting System (front) or the Spare Wheel Antenna Bracket (rear). Note the upper 2/3rd of the Antenna Main Assembly is kept clear of the vehicle’s hood and other metal panels. Best communications in all directions is ensured.
Recommended installation options on typical pickup vehicle using a Universal
Gibbet Mounting System (front) and a customer provided bracket (middle). Both
methods provide effective communications in all directions.
Recommended installation options on a typical sedan vehicle use a Universal
Gibbet Mounting System for both front and rear antenna locations. Note the
upper 2/3rd of the Antenna Main Assembly is optimally raised above the trunk
and hood of the vehicle.
NON-RECOMMENDED installation methods using a Universal Gibbet Mounting System (both at the rear) shown on a typical minivan or 4WD vehicles. Note the entire Antenna Main Assembly and partially Whip Section are OBSTRUCTED by vehicle metal panels. Communications will be affected.
For best communications, position the antenna as high as possible. Please use a Level Mark triangle as a reference when selecting a Universal Gibbet Raiser. The picture to the left indicates the preferred option selection. The picture to the right indicates an antenna installation that uses the optional NVIS- kit, for best communications on the 30–300km short ranges, and up to 1500 km medium ranges. Note, with the NVIS-kit installed, the antenna upper tuning range will be limited to 16 MHz.