Onwa ARGO 300, Руководство по эксплуатации

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General rules for best mobile antenna performanc
About SWR
e
1. Mount antenna on vehicle as high as possible.
2. The higher percentage of the antenna length mounted above rooftop, the better
performance.
3.Centre antenna in middle of selected location (i.e., boot, gutter or roof ).
4.Install an antenna cable line away from noise sources (ignition system, gauges
,etc.).
5.Be sure to mount antenna with a good mental-to-metal ground.
6. Prevent antenna cable damage.
Antenna performance may be peaked by slightly adjusting its length(1/8 to 1 )
using an SWR (standing wave ratio) meter. This meter is purchased separately or
the SWR can be checked professionally. Most antennas are factory-tuned,but this
adjustment may improve antenna efficiency. An SWR reading below 3:1 is desired,
as this indicates that over 75% of the transmit power is broadcast power is
broadcast into the air. The rest is reflected back into your transceiver and
dissipated as harmless heat.
See chart below. An SWR of 2:1 or below is good, 2.5 or even 3 is usually not user
noticeable or significant.
SWR Reading Output Power Transmitted
1 :1 100%
1.3 :1 98.3%
1.5 :1 96.0%
1.7 :1 93.3%
2 :1 89.0%
3 :1 75.0%
4 :1 64.0%
5 :1 58.0%
6 :1 49.0%
10 :1 33.0%
Roof Mount
Front Cowl Mount
Rear Deck Mount
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