Pll Adjustment; Transmitter Adjustment - Icom IC-A110 Service Manual

4-2 PLL ADJUSTMENT

ADJUSTMENT ADJUSTMENT CONDITION
Vdd
1 • Operating frequency :
VOLTAGE
118.000 MHz
• Receiving
PLL LOCK
1 • Operating frequency :
VOLTAGE
118.000 MHz
• Receiving
2 • Transmitting
TUNE
1 • Operating frequency :
VOLTAGE
118.000 MHz
• Receiving
REFERENCE
1 • Operating frequency :
FREQUENCY
136.950 MHz
• Connect an RF power meter or a
50 Ω dummy load to the antenna
connector.
• Transmitting

4-3 TRANSMITTER ADJUSTMENT

ADJUSTMENT ADJUSTMENT CONDITION
OUTPUT
1 • Operating frequency :
POWER
127.000 MHz
• No audio applied to the [MIC]
jack.
• Transmitting
MODULATION
1 • Operating frequecy :
DEPTH
127.000 MHz
• Connect an audio generator to
the [MIC] jack and set as :
1 kHz/10 mVrms
• Set a modulation analyzer as :
HPF
LPF
De-emphasis : OFF
Detector
• Pre-set R110 and R121 on the
MAIN unit to the center position.
• Transmitting
2 • Set an audio generator as:
1 kHz/1 mVrms
• Transmitting
HEAD SET
1 • Operating frequency :
MODULATION
127.000 MHz
• Connect an audio generator to
the [EXT MIC] jack and set as :
1 kHz/1 mVrms
• Transmitting
MEASUREMENT
UNIT
MAIN
MAIN
MAIN
Rear
panel
MEASUREMENT
UNIT
Rear
panel
Rear
panel
: OFF
: OFF
: (P–P)/2
Rear
panel
4 - 3
LOCATION
Connect a digital
multi-meter to drain
terminal of Q51.
Connect a digital
multi-meter to the
check point CP2.
Connect a digital
multi-meter to the
check point CP1.
Loosely couple the 136.9500 MHz
frequency counter
to the antenna con-
nector.
LOCATION
Connect an RF
power meter to the
antenna connector.
Connect a modula-
tion analyzer to the
antenna connector
through an attenua-
tor.
Connect a modula-
tion analyzer to the
antenna connector
through an attenua-
tor.
ADJUSTMENT
POINT
VALUE
UNIT ADJUST
13.5 V MAIN
0.5 V MAIN
0.5 V
0.7 V MAIN
MAIN
ADJUSTMENT
POINT
VALUE
UNIT ADJUST
9.0 W MAIN
90 % MAIN
30 %
30 % MAIN
R392
L41
L40
R59
X1
R150
R121
R110
R336