Icom IC-7700 - Manual (Page 99)

5-11
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AGC function
The AGC (auto gain control) controls receiver gain to
produce a constant audio output level even when the
received signal strength varies greatly.
The transceiver has 3 preset AGC characteristics (time
constant: fast, mid, slow) for non-FM mode.
The FM mode AGC time constant is fixed as ‘FAST’
(0.1 sec.) and AGC time constant cannot be
changed.
D D Selecting the preset value
q Select any non-FM mode.
w Push [AGC] (MF5) several times to select AGC fast,
AGC medium (MID) or AGC slow.
• Push and hold for 1 sec. to turn the AGC
function OFF.
D D Adjusting the AGC time constant
q Select any non-FM mode.
w Push , then rotate [AGC] control to adjust
the AGC time constant.
• [AGC VR] indicator above the switch lights green.
D D Setting the AGC time constant preset value
q Select any non-FM mode.
w Push and hold [AGC] (MF5) for 1 sec. to enter AGC
set mode.
e Push [AGC] (MF5) several times to select FAST time
constant.
r Rotate the main dial to set the desired time constant
for ‘AGC FAST.’
• AGC time constant can be set between 0.1 to 8.0 sec.
(depends on mode) or turned OFF.
• Push and hold [F-4•DEF] for 1 sec. to select a default
value.
t Push [AGC] (MF5) to select medium time constant.
y Rotate the main dial to set the desired time constant
for ‘AGC MID.’
• AGC time constant can be set between 0.1 to 8.0 sec.
(depends on mode) or turned OFF.
• Push and hold [F-4•DEF] for 1 sec. to select a default
value.
u Push [AGC] (MF5) to select slow time constant.
i Rotate the main dial to set the desired time constant
for ‘AGC SLOW.’
• AGC time constant can be set between 0.1 to 8.0 sec.
(depends on mode) or turned OFF.
• Push and hold [F-4•DEF] for 1 sec. to select a default
value.
o Select another non-FM mode. Repeat steps e to i
if desired.
!0 Push to exit the AGC set mode screen. EXIT/SET
AGC VR
AGC VR
[AGC] control AGC VR AGC
5
FUNCTIONS FOR RECEIVE
Mode Default Selectable AGC time constant
0.3 (FAST)
0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6, 2.0,
SSB 2.0 (MID)
2.5, 3.0, 4.0, 5.0, 6.0
6.0 (SLOW)
0.1 (FAST)
0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6, 2.0,
CW 0.5 (MID)
2.5, 3.0, 4.0, 5.0, 6.0
1.2 (SLOW)
RTTY
0.1 (FAST)
0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6, 2.0,
PSK
0.5 (MID)
2.5, 3.0, 4.0, 5.0, 6.0
1.2 (SLOW)
3.0 (FAST)
0.3, 0.5, 0.8, 1.2, 1.6, 2.0, 2.5, 3.0,
AM 5.0 (MID)
4.0, 5.0, 6.0, 7.0, 8.0
7.0 (SLOW)
FM 0.1 (FAST) Fixed
• Selectable AGC time constant (unit: sec.)