25
Installation and Connection
Installing the Radio
About the
antenna
A good antenna installation is extremely important for transmission and reception
purposes. Note the following, as the type and characteristics of the antenna largely
determines whether the performance of the radio can be fully realized.
• Use an antenna that suits the installation conditions and application objective.
• Use an antenna that suits the operating frequency band.
•
Use an antenna and a co-axial cable with a characteristic impedance of 50Ω.
• Adjust the VSWR (standing wave ratio) until it is 1.5 or less for an antenna with an
adjusted impedance of 50Ω.
• Keep the co-axial cable routing length as short as possible.
Install the antenna
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Antenna installation in a mobile unit
Mount the antenna base at the rear of the car (rear bumper, trunk, rear gate, etc.) and
then attach the antenna to the base.
Cautions
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Ensure that the antenna base is securely grounded to the car body.
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Avoid routing the co-axial cable enclosed with a commercial car antenna cable.
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Do not allow rain water or moisture to penetrate the cable or connectors when laying the co-axial
cable inside the car.
Bumper type
Trunk type
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Antenna installation in a fixed station
There are omni-directional, and directed array antennas for use in an outdoor setting.
• Omni-directional antennas such as the GP (Ground Plane) antenna are suitable for
communications between a local station and mobile stations in all direction.
• Directional antennas such as the Yagi antenna are suitable for communications
between a base station and a remote station in a specific direction.
