Icom IC-705, Basic Manual, Page: 38 / 96

4-5
BASIC MANUAL
4
RECEIVING AND TRANSMITTING
Selecting the IF filter
SSB, CW, RTTY, and AM modes
The IC-705 has 3 IF filter passband widths for
each mode, and you can select them on the
FILTER screen.
You can set the IF filter to wide (FIL 1),
mid (FIL 2), or narrow (FIL 3).
1. Select the operating mode. (Example: USB)
2. Touch the filter icon for 1 second.
• Opens the FILTER (SSB) screen.
3. Touch the filter icon several times to select
FIL 1 (wide), FIL 2 (mid), or FIL 3 (narrow).
4. Touch [BW].
• Selects the passband width mode.
5. Rotate to select the passband
width.
L
You cannot change the passband width in the
FM, FM-D, WFM, or DV mode.
L
When you change the passband width, the
Digital Twin PBT setting value is reset to the
center position.
L
“BPF” is displayed when a band width less
than 500 Hz is selected in the SSB, CW, or
RTTY mode.
6. To close the FILTER screen, push .
TIP: When you set the IF filter to FIL2 or FIL3
in the FM mode, the transceiver will transmit in
the FM narrow mode.
Mode IF filter Selectable range (steps)
SSB
FIL 1 (3.0 kHz)
50 Hz to 500 Hz (50 Hz)/
600 Hz to 3.6 kHz (100 Hz)
FIL 2 (2.4 kHz)
FIL 3 (1.8 kHz)
SSB-D
FIL 1 (3.0 kHz)
50 Hz to 500 Hz (50 Hz)/
600 Hz to 3.6 kHz (100 Hz)
FIL 2 (1.2 kHz)
FIL 3 (500 Hz)
CW
FIL 1 (1.2 kHz)
50 Hz to 500 Hz (50 Hz)/
600 Hz to 3.6 kHz (100 Hz)
FIL 2 (500 Hz)
FIL 3 (250 Hz)
RTTY
FIL 1 (2.4 kHz)
50 Hz to 500 Hz (50 Hz)
600 Hz to 2.7 kHz (100 Hz)
FIL 2 (500 Hz)
FIL 3 (250 Hz)
AM
AM-D
FIL 1 (9.0 kHz)
200 Hz to 10.0 kHz (200 Hz) FIL 2 (6.0 kHz)
FIL 3 (3.0 kHz)
FM
FM-D
DV
FIL 1 (15 kHz)
Fixed FIL 2 (10 kHz)
FIL 3 (7.0 kHz)
WFM FIL 1 (200 kHz) Fixed
Selecting the IF filter shape
SSB and CW modes
You can set the IF filter shape for each mode.
1. Select the operating mode. (Example: USB)
2. Touch the filter icon for 1 second.
• Opens the FILTER (SSB) screen.
3. Touch [SHARP] or [SOFT].
4. To close the FILTER screen, push .
• SHARP
This selection is to emphasize the passband width of
the filter. The filter has an almost ideal shape factor.
Signals that are out of the passband are extremely
filtered out, and it gives you better audio quality.
• SOFT
The filter shoulders are roundly formed as in analog
filters. This decreases noise components in the
high and low frequencies of the filter passband,
and increases the S/N of the target signal. These
characteristics play an effective role in picking up
very weak signals in the 50 MHz band, for example.
The shape factor is retained, and the sharpness of
the bandpass is excellent.
You can reset to the default settings
by touching this key for 1 second.