Icom IC-7400 Instruction Manual page 15

• When functioning as RF gain control
(Squelch is fixed open; SSB, CW, RTTY only)
Adjustable
range
Minimum RF gain
• When functioning as squelch control
(RF gain is fixed at maximum.)
Noise squelch (FM mode)
Noise squelch
threshold
(FM mode)
Squelch is
open.
Shallow
While rotating the RF gain control, noise may be
heard. This comes from the DSP unit and does not
indicate an equipment malfunction.
u MIC GAIN CONTROL [MIC GAIN]
Adjusts microphone input gain.
• The transmit audio tone in SSB, AM and FM modes can
be adjusted in tone control set mode. (p. 88)
✔ How to set the microphone gain.
Set the [MIC] control so that the ALC meter sometimes
swings during normal voice transmission in SSB mode.
Make sure that voice peak readings do not exceed the ALC
range brackets on the meter.
Recommended level for
an Icom microphone
Decreases
MIC GAIN
i AF CONTROL [AF] (inner control)
Varies the audio output level from the speaker.
AF
Decreases
No audio output
o RF POWER CONTROL [RF PWR]
Continuously varies the RF output power from min-
imum to maximum
(less than 5 W*)
* AM mode: less than 5 W to 40 W
Decreases
RF PWR
Maximum
RF gain
S-meter squelch
threshold
S-meter
squelch
Deep
Increases
RF/SQL
Increases
Max. audio output
.
(100 W*)
Increases
PANEL DESCRIPTION
!0 CW PITCH CONTROL [CW PITCH] (p. 28)
Shifts the received CW audio pitch and monitored
CW audio pitch without changing the operating fre-
quency.
• The pitch can be changed from 300 to 900 Hz in approx.
25 Hz steps.
Decreases
CW PITCH
!1 ELECTRONIC CW KEYER SPEED CONTROL
[KEY SPEED] (p. 28)
Adjusts the internal electronic CW keyer's speed.
• 6 wpm (min.) to 60 wpm (max.) can be set.
Slow
KEY SPEED
!2 AUTO NOTCH/MANUAL NOTCH SWITCH
[A/NOTCH] (p. 52)
Toggles the notch function between manual and au-
tomatic when pushed.
• "NOTCH" appears when manual; "A NOTCH" appears
when automatic notch is selected.
!3 NOTCH CONTROL [NOTCH] (outer control; p. 52)
Adjusts the notch filter frequency to remove an in-
terfering signal.
NR
Low frequency
!4 ANTENNA SELECTOR SWITCH [ANT] (p. 74)
Switches the antenna connector selection between
ANT1 and ANT2 when pushed.
!5 NOISE REDUCTION LEVEL CONTROL [NR]
(inner control; p. 52)
Adjusts the noise reduction level when the noise re-
duction is in use. Set for maximum readability.
NR
Decreases
OFF
!6 ANTENNA TUNER SWITCH [TUNER] (pgs. 75, 76)
➥ Turns the antenna tuner ON and OFF
when pushed momentarily.
➥ Starts to tune the antenna manually when
pushed for 1 sec.
• When the tuner cannot tune the antenna, the tuning
circuit is bypassed automatically after 20 sec.
!7 NOISE REDUCTION SWITCH [NR] (p. 52)
Switches the noise reduction ON and OFF.
• "NR" appears while the noise reduction is activated.
1
Increases
Fast
NOTCH
High frequency
NOTCH
Increases
(bypass)
2