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7-4
7
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) 0.1 (Fixed)
• Selectable AGC time constant
(unit: seconds)
■
AGC function control
The AGC (Automatic Gain Control) controls receiver
gain to produce a constant audio output level, even
when the received signal strength varies greatly.
The transceiver has three preset AGC settings (time
constants: fast, mid, slow) for non-FM modes.
The FM mode AGC time constant is fixed as ‘FAST’
(0.1 seconds) and the AGC time constant cannot be
selected.
D
Selecting the preset value
Select a non-FM mode.
q
Push the Multi-function [AGC](
w
) key several times
to select AGC fast, mid or slow.
• Hold down [AGC VR] for 1 second to turn OFF the AGC
function.
[EXIT/SET]
[AGC VR]
[AGC] control
(F) Function keys
AGC indicator
[MAIN DIAL]
(
≈
) Multi-function keys
• When selecting “AGC VR”
• The AGC screen
• When selecting “AGC-MID”
D
Setting the AGC time constant preset value
D
Adjusting the AGC time constant
Select a non-FM mode.
q
Push [AGC VR], then rotate the [AGC] control to ad
-
w
just the time constant.
• The [AGC VR] indicator lights.
• “VR” is displayed to the right of the Multi-function [AGC]
(
) key.
• To set the time constant to fast, rotate to the right. And to
set the time constant to slow, rotate to the left.
Select a non-FM mode.
q
Push the Multi-function [AGC](
w
) key several times
to select AGC fast, mid or slow.
Hold down the Multi-function [AGC](
e
) key for 1 sec-
ond.
• The AGC screen is displayed.
Rotate [MAIN DIAL] to set the desired time con-
r
stant.
• The selectable time constant is shown to the right.
• Hold down [DEF](F) for 1 second to select the default
value.
• While in the AGC Set mode, you can select the AGC or
the operating mode.
Push [EXIT/SET].
t
• Exits the AGC screen.
NOTE: When you are receiving a weak signal, and
a strong signal is momentarily received, the AGC
function quickly reduces the receiver gain. When
that signal disappears, the transceiver may not re-
ceive the weak signal because of the AGC action. In
that case, select AGC fast, or hold down [AGC-VR]
for 1 second to turn OFF the time constant.