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48
5
FUNCTIONS FOR RECEIVE
2001 NEW
■
AGC function
The AGC (auto gain control) controls receiver gain to
produce a constant audio output level even when the
received signal strength is varied by fading, etc.
The transceiver has 3 AGC characteristics (time con-
stant; fast, mid, slow) for non-FM modes.
The FM mode AGC time constant is fixed as ‘FAST’
(0.1 sec.) and AGC time constant cannot be se-
lected.
D
D
AGC speed selection
q
Select a non-FM mode.
w
While
M1
is selected, push [F1
AGC
] several times
to select AGC
F
, AGC
M
, AGC
S
or AGC OFF.
“AGC OFF” appears when AGC time constant OFF
is set with one of FAST, MID or SLOW setting in
AGC set mode.
D
D
Setting the AGC time constant
q
Select the desired mode other than FM mode.
w
While
M1
is selected, push [F1
AGC
] for 1 sec. to
enter AGC set mode.
e
Push one of [F2
FAST
], [F3
MID
] or [F4
SLOW
] to se-
lect the desired AGC speed to be set.
• An underline appears below the time constant indication.
r
Rotate the tuning dial to set the desired time con-
stant.
• AGC time constant can be set between 0.1 to 8.0 sec.
(depends on mode) or turned OFF.
• Push [F2
FAST
], [F3
MID
] or [F4
SLOW
] for 1 sec. to se-
lect a default value each for fast, mid. and slow, respec-
tively.
t
Select another mode other than FM. Repeat steps
e
and
r
if desired.
y
Push [MENU] to exit the AGC set mode.
• Selectable AGC time constant
(unit: sec.)
Mode
Default
Selectable AGC time constant
0.3 (FAST)
OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6
SSB
2.0 (MID)
2.0, 2.5, 3.0, 4.0, 5.0, 6.0
6.0 (SLOW)
0.1 (FAST)
OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6
CW
0.5 (MID)
2.0, 2.5, 3.0, 4.0, 5.0, 6.0
1.2 (SLOW)
0.1 (FAST)
OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6
RTTY 0.5 (MID)
2.0, 2.5, 3.0, 4.0, 5.0, 6.0
1.2 (SLOW)
3.0 (FAST)
OFF, 0.3, 0.5, 0.8, 1.2, 1.6, 2.0, 2.5
AM
5.0 (MID)
3.0, 4.0, 5.0, 6.0, 7.0, 8.0
7.0 (SLOW)
FM
0.1 (FAST)
Fixed
[F1
AGC
] Mode switches
: Medium AGC speed
: Slow AGC speed
: Fast AGC speed
: AGC is not activated
F 1
F 2
F 3
F 4
F 5
F 1
F 2
F 3
F 4
F 5
F 1
F 2
F 3
F 4
F 5
A G C D U P C M P T B W S C P
Push [F1] for 1 sec.
Selected mode
Appears under the selected AGC
speed’s time constant indication.
Push [F2] for 1 sec. to select the default value in
this case.
• When AGC fast is selected
IC-7400.qxd 02.4.2 11:35 Page 48