Hy-Gain AV-640, Инструкция по эксплуатации и сборке

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Antenna Mast
The recommended support mast for the AV-640 is steel water pipe between the sizes of 1-
1/4" OD to 2 1/2" OD and with a length that will place the antenna base at a safe height.
Do not use
thin walled conduit, aluminum tubing, or "TV" mast. The AV-640 is designed
to operate at a height of 8 or more feet for proper performance. Placement on the side of a
house or garage at eaves level is acceptable as long as the counterpoise whips will not be in
contact any snow on the roof Placement above metal roofs is acceptable if the antenna
base is at least 5 feet or more above the metal surface.
Antenna Grounding
Although the AV-640 is designed to operate efficiently without the requirement of an earth
ground, SAFETY GROUNDING must still be provided to protect equipment, property
and persons from the hazards of lightning strikes and other weather related electrical
discharges. In addition the coaxial cable feeding the antenna should have the shield
grounded to eliminate the risk of any indoor equipment failure from allowing hazardous
voltages from appearing indoors and creating a shock hazard. The support mast should be
grounded with a large diameter ground wire.
The AV-640 is DC grounded for static discharge. This is accomplished with a choke coil
in the Matching Unit. This coil could fail under high voltage spikes from a near or direct
lightning strike.
Additional protection can be accomplished by grounding the shield of the coax where it
enters the building to a good earth ground or directly burying the cable in the earth for
several feet before it enters the building. The coaxial cable should be totally disconnected
from the station during threatening weather conditions for maximum lightning
protection.
Antenna Guying
For normal operation up to 80 mph winds, the AV-640 will not require guying. For
extreme locations such as tall building rooftops, a safety guy is recommended. Use
Dacron® rope to guy the center radiator. Attach ropes 14 feet above the antenna base.
Use care not to disturb the radiator stubs.
Customer Supplied Components
• Quality low-loss 50 ohm coax cable with PL-259 connectors
• VSWR Analyzer (MFJ-259B or equiv.) or HF transceiver with VSWR meter
• Mounting mast with required hardware to provide sturdy support