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5 - 3
5-4 RECEIVER ADJUSTMENTS
SENSITIVITY
SQUELCH
• Operating channel : ch16
• [SQUELCH] control :
Max. counterclockwise
• Connect an SSG to the antenna
connector and set as:
Frequency
: 156.800 MHz
Level
: 100 µV*
(–67 dBm)
Modulation
: 1 kHz
Deviation
: ±3.5 kHz
• Receiving
• Operating channel : ch16
• [SQUELCH] control :
Max. counterclockwise
• Connect an SSG to the antenna
connector and set as:
Frequency
: 156.800 MHz
Level
: 0.22 µV*
(–120 dBm)
Modulation
: 1 kHz
Deviation
: ±3.5 kHz
• Receiving
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
1
1
MAIN
MAIN
Connect the distor-
tion meter to the
[EXT SP] jack with a
4
Ω
load.
Connect a DC volt-
meter to the check
point CP2.
Less than 0.32 µV
1.0 V
MAIN
Verify
R16
,
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit.
5-3 TRANSMITTER ADJUSTMENTS
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 J4
(pin 3) on the MAIN unit with an
AC millivoltmeter and set as:
Frequency
: 1 kHz
Level
: 45 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.
26 W
±4.3 kHz
MAIN
MAIN
R71
R138