Tuning Control - Icom IC-25A Instruction Manual

НОМ ТО ТОМЕ
The following instructions are for tuning in any mode. Please read carefully and understand fully
before turning ON your unit. Proper tuning is necessary for optimum operation.
PRESET FREQUENCIES
When the POWER Switch is turned ON, the frequency display will be "5.00" representing 145.000
MHz (IC-25A : "6.01" representing 146.010MHz). The frequencies of the VFO's and the Memory
Channels are preset so that they start from the frequencies shown above whenever the IC-25A/E is
· turned ON.
TUNING CONTROL
Rotating the Tuning Knob clockwise increase the frequency; turning it counterclockwise decreases
the frequency in 5KHz steps when VFO "А" is used, or in 25KHz (IC-25A : 15KHz) steps when
VFO "B" is used.
The click stops of the knob change in 5KHz steps or 25KHz steps (IC-25A : 15KHz steps). One
complete rotation of the tuning knob results frequency increases or decreases of a 250KHz or
1,250KHz (IC-25A : 750KHz).
When you reach 145.995MHz, turning the Tuning Control knob clockwise will bring the operating
frequency to 144.000MHz, the lowest edge, and you can continue increasing the frequency from
there by continuing to rotate the knob clockwise. The VFO endless system functions in the same
way when decreasing the frequency from 144.000MHz, and will prevent you from inadvertently
operating out of the amateur radio band. (1С-2БА : 145.995MHz and 144.000MHz should be read
as 148.195MHz and 143.800MHz.)
. VFO/MEMORY CHANNEL SWITCH апа VFO SWITCH
The CPU in the IC-25A/E contains two "МЕО" for both receiving and transmitting. The VFO's
are labeled "А" VFO and "B" VFO and are selectable with the VFO Switch, when the VFO/
MEMORY CHANNEL Switch is the VFO position. The dual VFO system gives the IC-25A/E
many very convenient features. Please read this section very carefully and perform the operation
several times until you are comfortable with the system. Try the example for practice!
1. "A" VFO is for both transmitting and receiving and is selected by placing the VFO Switch in
the "A" (out) position. The transmit and receive frequency will be controlled by "A" VFO,
displayed on the frequency display and stored in "А" memory.
2. "B" VFO is for both transmitting and receiving and is selected by placing the VFO Switch in
the "B" (in) position. The transmit and receive frequency will be controlled by "B" VFO,
displayed on the frequency display, and stored in "B" memory.
NOTE: The memory channel positions are described in the "MEMORY CHANNEL OPERA-
TION" on page 13.
Ш When the IC-25A/E is first turned ON, 145.000MHz (IC-25A : 146.010MHz) is preset into
the VFO "A" and VFO "B".
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