Icom IC-551D Instruction Manual page 19

1. Тһе Tuning knob tension will become tighter by turning the brake adjustment screw clock-
wise, and will become looser by turning the screw counterclockwise. |
2. While performing this adjustment, the Tuning knob must be turned continuously as the screw
is adjusted in order to set the tension for a comfortable touch.
DIAL LOCK SWITCH
After the IC-b51D is set at a certain frequency for rag chewing, mobile operation, etc., turning the
Dial Lock switch to the ON (down) position, the VFO is locked at the displayed frequency, thus
inactivating the operation of the tuning knob. To change the frequency, the Dial Lock must first
be disengaged by turning the dial lock switch again to OFF (up) position, the frequency will change
with the direction of the tuning knob rotation. |
TS (TUNING SPEED) BUTTON
Pushing the TS Button, the TS indicator LED will be illuminated. While this indicator is ON, the
. frequency is increased or decreased in 1KHz steps in all modes, and the smaller vernier marks on
the Knob correspond to 1KHz steps.
VFO SELECT SWITCH
The CPU in the IC-551D contains two "VFO's" for both receiving and transmitting. The VFO's are
labeled "A" VFO and "B" VFO and are selectable with the VFO Select Switch. This dual VFO
system gives the IC-551D 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!
1. "A" VFO is for both transmitting and receiving and is selected by placing the VFO Select
Switch in the "A" position. The transmit and receive frequency will be controlled by "А"
VFO, displayed on the frequency display and stored іп "А" memory.
2. "B" VFO is for both transmitting and receiving and is selected by placing the VFO Select
Switch in the "В" position. The transmit and receive frequency will be controlled by "В"
VFO, displayed on the frequency display, and stored in "В" memory.
3. RA-TB: The receive frequency is controlled by "А" VFO and the transmit frequency is
controlled by "B" VFO. Both frequencies are stored in their respective memories, and
displayed during their respective operation times ("А" frequency during receive, and "В"
frequency during transmit).
4. RB-TA: The receive frequency is controlled by "В" VFO and the transmit frequency is
controlled by "А" VFO, the reverse of the above. Again, both frequencies are stored in their
respective memories, and displayed during their respective operation times (this time "В"
frequency during receive and "А" frequency during transmit).
b. А-В: Instantly sets the frequency of "B" VFO to the same as that of "A" VFO. This is
very convenient when the RIT control can not cover the transmitting and receiving frequencies
differ by more than 1KHz or when you want to OSO with several KHz split transmitting and
receiving frequencies. |
NOTE: The MS, 1, [2], and [3] positions are described in the "MEMORY CHANNEL ОРЕ-
RATION" on page 19.
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