Ref Adjustments - Icom IC-7851 Servise Manual

3-4 REF ADJUSTMENTS

• REF adjustment screen
ADJUSTMENT
REFERENCE 1 Before starting the adjustment:
FREQUENCY Wait for 5 minutes, after turning ON the power.
-PREPARATION- 2 • Connect a Frequency Counter to the [REF I/O] terminal.
-ADJUSTMENT- 3 1) Push [F-2] (REF).
2) Push [F-1] (OSC).
3) Turn the main dial to set the reference frequency.
4) Push [F-7] (SET).
DIGI-SEL knobs 4 1) Push [F-2] (DIGI-VR).
2) Set the DIGI-SEL VR (both main and sub) to the center po-
3) Push [F-7] (SET).
FILTER 5 1) Push [F-3] (FIL CAL) to enter the fi lter calibration mode.
CALIBRATION 2) Push [F-7] (SET).
(RF-A)
FILTER 6 • Push [F-7] (SET).
CALIBRATION • Returns to the Reference adjustment menu.
(RF-B)
7 • Push [F-4] (EXIT).
OPERATION
• Enters to the Reference adjustment menu.
• Returns to the Reference adjustment menu.
sition.
• Returns to the Reference adjustment menu.
• Returns to the main adjustment menu.
3-8
[DIGI-SEL] knobs
ADJUSTMENT
VALUE
ITEM/POINT
–
10.000,000,0
(±0.1 Hz)
[REF OSC]
Center
position
[DIGI-SEL] knobs
(Automatic
[Roofi ng 1.2k(A)] adjustment)
(Automatic
[Roofi ng 1.2k(B)]
adjustment)
Push [F-7].
–
–
MHz