Pll adjustment, Frequency adjustment, 2 pll adjustments – Icom IC-910H User Manual
Page 20: 3 frequency adjustment
5 - 2
5-2 PLL ADJUSTMENTS
30.2 MHz
LEVEL
REFERENCE
FREQUENCY
144M LOCK
VOLTAGE
440M LOCK
VOLTAGE
MAIN BFO
LEVEL
SUB BFO
LEVEL
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
1
1
2
1
2
3
1
2
3
1
2
• Display frequency: Any
• Receiving
• Display frequency: Any
• Receiving
This adjustment must be performed
at 5 minutes later after power ON.
• Display frequency: 173.9800 MHz
• Mode
: USB
• Receiving
• Display frequency: 136.0200 MHz
• Receiving
• Display frequency: 155.0000 MHz
• Receiving
• Display frequency: 479.9800 MHz
• Mode
: USB
• Receiving
• Display frequency: 420.0200 MHz
• Receiving
• Display frequency: 450.0000 MHz
• Receiving
• Display frequency: Any
• Mode
:USB
• Receiving
• Sub display freq. : Any
• Mode
:USB
• Receiving
PLL
PLL
PLL
PLL
PLL
PLL
Connect an RF volt-
meter or spectram
analyzer to check
point J541.
Connect an RF volt-
meter or spectram
analyzer to check
point P551.
Connect a frequency
counter to check
point P551.
Connect a digital
multimeter or oscillo-
scope to check point
CP100.
Connect an RF volt-
meter to check point
P251.
Connect a digital
multimeter or oscillo-
scope to check point
CP300.
Connect an RF volt-
meter to check point
P421.
Connect an RF volt-
meter to check point
P601.
Connect an RF volt-
meter to check point
P701.
–10 dBm (or more than
–11.5 dBm, when R570
is in maximum posi-
tion.)
Maximum level
(–13 dBm to –7dBm)
60.400000 MHz
2.7 V
0.6 V to 1.6 V
–10 dBm to –4 dBm
3.4 V
0.5 V to 1.5 V
–16 dBm to –10 dBm
–11 dBm to –5 dBm
–11 dBm to –5 dBm
PLL
PLL
PLL
PLL
PLL
PLL
R570
Adjust in
sequence
L551, L552
s e v e r a l
times.
The trimmer
capacitor of
X512.
L193
Verify
Verify
C402
Verify
Verify
Verify
Verify
5-3 FREQUENCY ADJUSTMENT
FM TX-LO
FREQUENCY
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
1 • Display frequency: Any
• Mode
: FM
• Disconnect P501, P502 (PA unit)
from J51 and J52 on the MAIN unit.
• Apply no audio signals to [MIC]
connector.
• Transmitting
MAIN
Connect a frequency
counter to check
point CP51.
10.85000 MHz
MAIN
L255
After adjustment, connect P501, P502 (PA unit) to J51, J52 on the MAIN.