Icom IC-910H Service Manual page 60

5-2 PLL ADJUSTMENTS
ADJUSTMENT ADJUSTMENT CONDITION
30.2 MHz 1 • Display frequency: Any
LEVEL • Receiving
1 • Display frequency: Any
REFERENCE
FREQUENCY • Receiving
2 This adjustment must be performed
at 5 minutes later after power ON.
1 • Display frequency: 173.9800 MHz
144M LOCK
VOLTAGE • Mode
• Receiving
2 • Display frequency: 136.0200 MHz
• Receiving
3 • Display frequency: 155.0000 MHz
• Receiving
440M LOCK 1 • Display frequency: 479.9800 MHz
• Mode
VOLTAGE
• Receiving
2 • Display frequency: 420.0200 MHz
• Receiving
3 • Display frequency: 450.0000 MHz
• Receiving
MAIN BFO 1 • Display frequency: Any
LEVEL • Mode
• Receiving
SUB BFO 2 • Sub display freq. : Any
LEVEL • Mode
• Receiving
5-3 FREQUENCY ADJUSTMENT
ADJUSTMENT ADJUSTMENT CONDITION
1 • Display frequency: Any
FM TX-LO
FREQUENCY • Mode
• Disconnect P501, P502 (PA unit)
from J51 and J52 on the MAIN unit.
• Apply no audio signals to [MIC]
connector.
• Transmitting
After adjustment, connect P501, P502 (PA unit) to J51, J52 on the MAIN.
MEASUREMENT
UNIT
PLL
PLL
PLL
: USB
PLL
: USB
PLL
:USB
PLL
:USB
MEASUREMENT
UNIT
MAIN
: FM
5 - 2
LOCATION
Connect an RF volt- –10 dBm (or more than
meter or spectram –11.5 dBm, when R570
analyzer to check is in maximum posi-
point J541. tion.)
Connect an RF volt- Maximum level
meter or spectram (–13 dBm to –7dBm)
analyzer to check
point P551.
Connect a frequency 60.400000 MHz
counter to check
point P551.
Connect a digital
multimeter or oscillo-
scope to check point
CP100.
0.6 V to 1.6 V
Connect an RF volt- –10 dBm to –4 dBm
meter to check point
P251.
Connect a digital
multimeter or oscillo-
scope to check point
CP300.
0.5 V to 1.5 V
Connect an RF volt- –16 dBm to –10 dBm
meter to check point
P421.
Connect an RF volt- –11 dBm to –5 dBm
meter to check point
P601.
Connect an RF volt- –11 dBm to –5 dBm
meter to check point
P701.
LOCATION
Connect a frequency 10.85000 MHz
counter to check
point CP51.
ADJUSTMENT
POINT
VALUE
UNIT ADJUST
PLL
PLL Adjust
sequence
L551, L552
s e v e r a l
times.
The trimmer
capacitor of
X512.
2.7 V PLL
3.4 V PLL
PLL
PLL
ADJUSTMENT
POINT
VALUE
UNIT ADJUST
MAIN
R570
in
L193
Verify
Verify
C402
Verify
Verify
Verify
Verify
L255