Icom YPL 880, Instruction Manual

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1
ANTENNA SYSTEM
2001 NEW
n
Antenna for ship
Required antenna element length
Required antenna element length to achieve full
performance varies according to the lowest frequency:
The longer the antenna element, the better the
antenna efficiency.
Undesirable antenna element lengths
AVOID
multiples of 1 ⁄
2
λ
(half wavelength) for
antenna 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
f
×
1
2
n
×
[Example]
At an operating frequency of 16 MHz, avoid the
following antenna element lengths:
L =
300
16
×
1
2
n
×
9.4, 18.8, ...
1 m 39 inches
For example, if 15 m is selected for an antenna
element length, you have no problem in the 1.6–25
MHz marine bands range.
Insulator
Backstay operates as
a long-wire antenna.
Insulator
Whip antenna
NOTE: Keep antennas as far away from other
objects as possible, especially metal objects.
The lowest frequency Required antenna element length
1.6 MHz band
7 m; 23.0 feet or longer
4 MHz band 3 m; 9.8 feet or longer