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*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit.
5-3 TRANSMITTER ADJUSTMENTS
5-2 PLL ADJUSTMENTS
5 - 2
LOCK
VOLTAGE
REFERENCE
FREQUENCY
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
1
2
3
4
1
• Operating channel : ch16
• Receiving
• Operating channel : ch116
• Receiving
• Operating channel : ch16
• Output power
: Low
• Transmitting
• Operating channel : ch116
• Output power
: Low
• Transmitting
• Operating channel : ch16
• Output power
: Low
• Connect an RF power meter or a
50
Ω
dummy load to the antenna
connector.
• Transmitting
MAIN
Rear
Panel
Connect a digital
multi-meter or oscil-
loscope to check
point CP1.
Connect a digital
multi-meter or oscil-
loscope to check
point CP2.
Loosely couple the
frequency counter
to the antenna con-
nector.
2.5 V
3.4–4.1 V
2.8 V
2.5–3.5 V
156.8000 MHz
MAIN
MAIN
L13
Verify
L10
Verify
C70
OUTPUT
POWER
FREQUENCY
DEVIATION
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
1
1
• Operating channel : ch16
• Output power
: High
• Transmitting
• Operating channel : ch16
• Output power
: Low
• Connect an audio generator to J7
(pin 5) with an AC millivoltmeter
and set as:
Frequency
: 1 kHz
Level
: 30 mV
• Set an FM deviation meter as:
HPF
: OFF
LPF
: 20 kHz
De-emphasis
: OFF
Detector
: (P–P)/2
• Transmitting
Rear
Panel
Rear
Panel
Connect an RF
power meter to the
antenna connector.
Connect an FM
deviation meter to
the antenna con-
nector through an
attenuator.
25 W
±4.3 kHz
MAIN
MAIN
R84
R172