Icom IC-7851 Instruction Manual page 141

7
FUNCTIONS FOR RECEIVE
■
IF filter selection (Continued)
D 1.2 kHz Filter calibration
The IC-7851 has the 1.2 kHz Optimum Roofing Filter
operating at 64 MHz. The characteristic of this Roofing
Filter may slightly vary, depending on the operating en-
vironment or after long usage. You can adjust it in the
Filter calibration mode.
You can automatically or manually adjust the filter.
Automatic adjustment
q
Hold down [FILTER] for 1 second.
• The Filter screen is displayed.
w
Select the desired mode.
e
Push [ROOFING](F) several times to select '1.2k.'
• '15k,' '6k,' '3k,' and '1.2k' are selectable.
r
Push [ADJ](F).
• Enters the Filter calibration mode.
t
Hold down [CAL](F) for 1 second to start the auto-
matic adjustment.
• "CAL" blinks.
• When the adjustment is successful, two beeps sound.
• If the adjustment fails, an error beep sounds.
y
Push [ADJ](F).
• Exits the Filter calibration mode.
Manual adjustment
q
Hold down [FILTER] for 1 second.
• The Filter screen is displayed.
w
Select the desired mode.
e
Push [ROOFING](F) several times to select '1.2k.'
• '15k,' '6k,' '3k,' and '1.2k' are selectable.
r
Push [ADJ](F).
• Enters the Filter calibration mode.
t
Rotate [MAIN DIAL] to adjust.
• The adjustable values are between 0% and 100%.
(±1100 Hz of the set value in 5 Hz steps)
• Adjust the appropriate value so that you can easily hear
a desired signal and undesired signals are reduced.
y
Push [ADJ](F).
• Exits the Filter calibration mode.
• When selecting "1.2 k" Roofing filter
• In the Filter calibration mode
(Automatic adjustment)
• In the Filter calibration mode
(Manual adjustment)
7-8
Blinks