1 ANTENNA SYSTEM
■Antenna for ship
Required antenna element length
Required antenna element length to achieve full per- formance varies according to the lowest frequency:
The lowest frequency | Required antenna element length |
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1.6 MHz band | 7 m; 23.0 feet or longer |
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4 MHz band | 3 m; 9.8 feet or longer |
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The longer the antenna element, the better the an- tenna efficiency.
Undesirable antenna element lengths
AVOID multiples of 1⁄2λ (half wavelength) for an- tenna element lengths, since tuning becomes difficult.
L : Antenna element length to be avoided [m]
f : Operating frequency [MHz]
n : Natural number (n = 1, 2, 3, ...)
L = 300 ⋅ | 1 | ⋅ n | |
2 | |||
f |
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[Example]
At an operating frequency of 16 MHz, avoid the fol- lowing antenna element lengths:
L = | 300 | ⋅ | 1 | ⋅ n | 9.4, 18.8, ... | |
16 | 2 | |||||
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1 m | 39 inches |
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For example, if 15 m is selected for an antenna ele- ment length, you have no problem in the
Insulator
Backstay operates as a
Insulator
Whip antenna
NOTE: Keep antennas as far away from other objects as possible, especially metal objects.
■Antenna for land operation
In some countries, HF transceivers can be used for land mobile operation. Ask your Icom Dealer for de- tails, since the radio law varies according to each country.
For land mobile operation on 4 MHz and above, an optional
Refer to the
Connect a suitable antenna element for a base sta- tion. To achieve full performance, refer to “Required antenna element length” above.
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