Icom IC-905, Основное руководство

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4-4
BASIC MANUAL
4
RECEIVING AND TRANSMITTING
AGC function control
SSB, CW, RTTY, and AM modes
The Automatic Gain Control (AGC) function controls
receiver gain to produce a constant audio output level,
even when the received signal strength greatly varies.
L
Each mode and band memorizes the AGC setting.
D
Selecting the AGC time constant preset
value
The transceiver has FAST, MID, and SLOW preset
AGC settings for all modes, except the FM, DV, DD,
and ATV modes.
1. Select the operating band and mode.
(Example: SSB, 144 MHz band)
2. Push .
• Opens the FUNCTION screen.
3. Touch [AGC] to select the desired time constant.
L
Touching [AGC] selects FAST, MID, or SLOW.
L
For FM, DV, DD, and ATV modes, FAST is fixed.
4. To close the FUNCTION screen, push .
NOTE: While you are receiving weak signals, and
a strong signal is momentarily received, the AGC
function quickly reduces the receiver gain. When that
signal disappears, the transceiver may not receive
the weak signal because of the AGC action. In that
case, select FAST, or touch [AGC] for 1 second to
open the AGC screen, and then select OFF.
D
Setting the AGC time constant
You can set the preset AGC time constant to a desired
value.
1. Select the operating mode. (Example: SSB)
2. Push .
• Opens the FUNCTION screen.
3. Touch [AGC] for 1 second.
• Opens the AGC (SSB) screen.
4. Touch FAST, MID, or SLOW. (Example: MID)
5. Rotate to set the time constant.
6. To close the AGC (SSB) screen, push .
Selectable AGC Time constant (unit: seconds)
Mode Default Adjustable time constant
LSB
USB
0.3 (FAST)
OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2,
1.6, 2.0, 2.5, 3.0, 4.0, 5.0, or 6.0
2.0 (MID)
6.0 (SLOW)
CW/
RTTY
0.1 (FAST)
OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2,
1.6, 2.0, 2.5, 3.0, 4.0, 5.0, or 6.0
0.5 (MID)
1.2 (SLOW)
AM
3.0 (FAST)
OFF, 0.3, 0.5, 0.8, 1.2, 1.6, 2.0,
2.5, 3.0, 4.0, 5.0, 6.0, 7.0, or 8.0
5.0 (MID)
7.0 (SLOW)
FM/DV/
DD/ATV 0.1 (FAST) Fixed
You can reset to the default setting
by touching this key for 1 second.