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5 - 4
ADJUSTMENT ITEM
ADJUSTMENT CONDITIONS
OPERATION
VALUE
144 MHz
BAND
DEVIATION
(Left Band)
(Band
Low)
(FM)
[L FMD]
1
•
•
•
Connect a Modulation Analyzer to
the antenna connector (J1) through
an attenuator.
Connect an Audio Generator to the
JIG cable (See the page 5-1 for the
connector and setting details).
Transmitting
Rotate the right band’s
[DIAL]
to
adjust the deviation, then push
the right band’s
[MAIN•BAND]
key during transmit.
±4.2 kHz
(FM-N)
[L FMD]
2
±2.1 kHz
(Band
Center)
(FM)
[L FMD]
3
±4.2 kHz
(FM-N)
[L FMD]
4
±2.1 kHz
(Band
High)
(FM)
[L FMD]
5
±4.2 kHz
(FM-N)
[L FMD]
6
±2.1 kHz
144 MHz
BAND
MODULATION
BALANCE
(Left Band)
(Band
Low)
(FM)
[L FMB]
1
•
•
•
•
Connect a Modulation Analyzer to
the antenna connector (J1) through
an attenuator.
Connect an oscilloscope to the de-
tector terminal of the Modulation
Analyzer.
No audio signals are applied to the
JIG cable (See the page 5-1).
Transmitting
Rotate the right band’s
[DIAL]
to
adjust the wave form, then push
the right band’s
[MAIN•BAND]
key during transmit.
(Square
Wave form)
(FM-N)
[L FMB]
2
(Band
Center)
(FM)
[L FMB]
3
(FM-N)
[L FMB]
4
(Band
High)
(FM)
[L FMB]
5
(FM-N)
[L FMB]
6
144 MHz BAND
DTCS MODULATION
(Left Band)
(FM)
[L MDT]
1
•
•
•
Connect a Modulation Analyzer to
the antenna connector (J1) through
an attenuator.
No audio signals are applied to the
JIG cable (See the page 5-1).
Transmitting
Rotate the right band’s
[DIAL]
to
adjust the deviation, then push
the right band’s
[MAIN•BAND]
key.
±0.8 kHz
(FM-N)
[L MDT]
2
144 MHz
CTCSS MODULATION
(Left Band)
(FM)
[L MCT]
1
•
•
•
Connect a Modulation Analyzer to
the antenna connector (J1) through
an attenuator.
No audio signals are applied to the
JIG cable (See the page 5-1).
Transmitting
Rotate the right band’s
[DIAL]
to
adjust the deviation, then push
the right band’s
[MAIN•BAND]
key .
±0.75 kHz
(FM-N)
[L MCT]
2
• CONNECTION FOR MODULATION ADJUSTMENTS
Fuses
20 A
DC power supply
(13.8 V/20 A)
⊕
−
MODULATION ANALYZER
(0.1–1 GHz)
ATTENUATOR
(40 dB/100 W)
To J1
OSCILLOSCOPE
(DC to 10 kHz)
<SETTING>
HPF :
OFF
LPF
: 20 kHz
De-emphasis : OFF
Detector :
(P-P)/2
IC-E2820
Black
Red
⊕
−
¤
DEVIATION ADJUSTMENT