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4-6
4-4 TRANSMIT ADJUSTMENTS (CONTINUED)
1)
Select an adjustment item by pushing [↑]/[↓] on the PC keyboard.
2)
Set or modify the adjustment value as specified by pushing [←]/[→], and then push [Enter] to store the value.
ADJUSTMENT
TRANSCEIVER’S
CONDITION
OPERATION
ADJUSTMENT
ITEM
VALUE
DEVIATION
-Verification-
(Transceiver)
1 • Operating channel: 16
• Transmitting
•
C
onnect the modulation analyzer to
the antenna connector through the
attenuator and set it to:
HPF:
OFF
LPF:
20 kHz
De-emphasis:
OFF
Detector:
(P–P)/2
•
C
onnect the audio generator and the
AC millivoltmeter to the FRONT MIC
JACK through the JIG cable, and set
it to:
Frequency:
1 kHz
Wave form: Sine wave
Level:
280 mV rms
–
±3.9~±4.3 kHz
(DSC)
2 • Operating channel: 70
• Transmitting
–
[DSC (1300Hz)]
±2.6 kHz ±10%
3
[DSC (2100Hz)]
±4.2 kHz ±10%
MODULATION
SENSITIVITY
-Verification-
1 • Operating channel: 16
• Transmitting
•
Set the
audio generator
to:
Level:
28 mV rms
[MSENS (INT)]
±2.7~±3.3 kHz
TX SIGNAL-TO-
NOISE RATIO
-Verification-
1 • Operating channel: 16
• Transmitting
•
C
onnect the modulation analyzer to
the antenna connector through the
attenuator and set it to:
HPF:
OFF
LPF:
20 kHz
De-emphasis:
OFF
Detector:
(P‒P)/2
•
C
onnect the AC millivoltmeter to the
modulation analyzer.
•
C
onnect the audio generator and the
AC millivoltmeter to the FRONT MIC
JACK, and set it to:
Frequency:
1 kHz
Wave form: Sine wave
•
Adjust the
audio generator
output level
so that the deviation on the
modulation
analyzer
becomes ±3.0 kHz.
•
The audio output level of the
modulation analyzer at this time is the
reference level (0 dB).
•
Turn off the output of the audio
generator and verify the difference
between the audio output level of the
modulation analyzer at that time and
the reference level.
–
More than
40 dB