Pll Adjustment - Icom ic-775 Service Manual

5-2
PLL
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITIONS
MEASUREMENT
VALUE
ADJUSTMENT
POINT
UNIT
LOCATION UNIT
ADJUST
REFERENCE
FREQUENCY
1
• Displayed frequency:
Any
•
R360 (PLL
unit)
:
Center
• Receiving
PLL
Connect a frequency
counter
to P3.
60.000000
MHz
PLL
L4
2
Connect an
RF
voltmeter
toP3.
Meiximum
level
(0
dBm
or
more)
L6,
L7
PLL-A
REFERENCE
LOOP LOCK
VOLTAGE
1
•
Displayed frequency: 7.99999
MHz
•
Mode
USB
•
Receiving
PLL
Connect a
digital multi-
meter or oscilloscope
to
R46.
3.2
V PLL
C47
PLL-A
MAIN
LOOP LOCK
VOLTAGE
1
•
Displayed frequency
:
7.99999
MHz
•
Receiving
PLL Connect a
digital
multi-
meter
or oscilloscope to
J12.
6.5
V
PLL
C86
2
• Displayed frequency:
14.99999
MHz
6.5
V C96
3
•
Displayed frequency: 21.99999
MHz 6.5
V Cl 07
4
•
Displayed frequency
:
29.99999
MHz 6.5
V C117
PLL-B
REFERENCE
LOOP LOCK
VOLTAGE
1
.
SPLIT
:
ON
•
Main frequency readout:
7.999999
MHz
•
Mode
:
USB
• Receiving
PLL
Connect a
digital multi-
meter or oscilloscope to
R141.
3.2
V PLL Cl 69
PLL-B
MAIN
LOOP LOCK
VOLTAGE
1
.
SPLIT
:
ON
•
Main frequency readout:
7.999999
MHz
• Receiving
PLL Connect a
digital
multi-
meter
or oscilloscope to
J14.
6.5
V PLL
C205
2
•
Main frequency readout:
14.999999
MHz
6.5
V
C218
3
•
Main frequency readout
:
21 .999999
MHz
6.5
V C229
4
•
Main
frequency readout:
29.999999
MHz
6.5
V
C239
5-2