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

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If the VSWR is less than 1.5:1 at the frequencies you operate, do not spend extra time
trying to improve the VSWR. Any improvements beyond 1.5:1 yield minimal gains in
antenna performance and cause excess wear on the antenna, roof or mast. Please note the
length of coax will vary the VSWR on certain bands. Lengths less than 50 feet have
stronger harmonic resonances than longer lengths. If a particular band will not properly
resonate, try adding 3-5 feet or more of coax. Record the resonant frequencies with and
without the added coax. There will be a change in resonant frequencies on one or more
bands. RF loss at HF is not a major problem with RG8X or larger coax. There will be a
minimal performance difference between a 50 ft. length and a 75 ft. length of coax.
To lessen the possibility of RFI/TVI, roll up 6-8 turns of coax 8" inches diameter
approximately one quarter wave (or multiple) from the base of the antenna. Use the
quarter wave length of the frequency that causes the greatest amount of
Maintenance
The AV-640 should be inspected mechanically at least once a year. Normal wear and tear
varies significantly with climate.
Anti-Oxidation paste such as NoAIOX® or others can be applied to the radiator tubing
sections. Use small amounts. Do not place the paste on the coax connector or inside of the
Matching Unit.
Inspect the inside of the Matching Unit on a regular basis. Remove dirt, bugs, or
questionable material. Look for any degradation of parts. High voltage static
discharges (lightning) may cause a failure to the small coil in the Matching Unit. This
coil is a protection device. Make sure it is in good shape.
Do not screw and unscrew the nylon insert nuts several times. If portable operation
is desired, use stainless steel hardware without the nylon locking feature.
The AV-640 may be painted. Clean all aluminum surfaces well to improve paint
adherence. Paint the antenna
after it is assembled and tuned. DO NOT PAINT
PLASTIC PARTS.
Technical Assistance
Technical assistance is available during normal business hours on weekdays. Hy-Gain
is located in the Central Time Zone. Our hours are 7:00 AM till 4:00 PM CST Monday
through Friday.
Hy-Gain can be reached by telephone, FAX, email and regular mail at the
following addresses:
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