Icom IC-756 - Manual (Page 30)

The received CW audio pitch and monitored CW
audio can be adjusted to suit your preferences (300
to 900 Hz) without changing the operating frequency. The received CW audio pitch can be adjusted in 3 Hz
steps.
■ APF function
The APF (Audio Peak Filter) changes the receive fre-
quency response by boosting a particular frequency
for better copying of desired CW signals. The peak
frequency can be adjusted with [APF] from 300 to 900
Hz manually. The boost frequency width can be se-
lected from 80, 160 or 320 Hz.
q Push [CW] to select CW mode.
w Push the [APF] switch to turn the audio peak filter
ON.
- The [APF] switch lights.
- “
,” etc. appears in the LCD.
e Rotate the [APF] control to adjust the center fre-
quency of the peak frequency.
r Push [APF] for 2 sec. to select the boost frequency
width of the audio peak filter between 80, 160 and
320 Hz.
- “ ,” “ ” or “ ” indicate the fre-
quency width.
t Push the [APF] switch momentarily to cancel the
audio peak filter.
320 320 APF APF 160 160 APF APF 1 80 80 APF APF
320 320 APF APF
■ CW reverse mode
CW-R (CW Reverse) mode receives CW signals with
a reverse side CW carrier point like that of LSB and
USB modes.
Use when interfering signals are near a desired signal
and you want to change the interference tone.
• Push [CW] for 2 sec. once or twice to select CW or
CW-R mode.
- Check the interfering tone.
• Receive audio tone response
27
4
RECEIVE AND TRANSMIT
14.100.00 VFO VFO
USB USB
USB USB
14.205.00 14.205.00
T X T X
1
ANT ANT
1
METER METER
Po Po
2.4k 9 2.8k 455 12:34 320 APF
[APF] switch
[APF]
control
APF indicator
■ CW pitch control
■ RTTY reverse mode
Received characters are occasionally garbled when
the receive signal is reversed between MARK and
SPACE. This reversal can be caused by incorrect
TNC connections, settings, commands, etc. To receive a reversed RTTY signal correctly, select
RTTY-R (RTTY Reverse) mode.
• Push [RTTY] for 2 sec. once or twice to select RTTY
or RTTY-R mode.
- Check the receive signal.
BFO
1/3 octave
Push for 2 sec.
Desired signal
(600 Hz)
CW mode (USB side)
Interference
(800 Hz)
BFO
1/2 octave
Desired signal
(600 Hz)
CW-R mode (LSB side)
Interference
(400 Hz)
CW