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5 - 2
5-2 SOFTWARE ADJUSTMENTS
REFERENCE
FREQUENCY
[REF]
CENTER
VOLTAGE
BFO
[LSB]
[USB]
[CW]
SSB-IF
SHIFT
[LSB-IFS]
[USB-IFS]
1
1
2
1
2
3
1
2
3
4
• Connect the frequency counter to the check point
CP18 on the RF unit.
• Receiving
• Dual watch mode
: ON
• Set the receiver to [A-BAND] and FM mode.
• Operating frequency
: 145.100 MHz
• Connect an SSG to the antenna connector and set as
Level
: 1 mV* (–47 dBm)
Frequency
: 145.100 MHz
Modulation
: OFF
• Connect the Digital multimeter to the check point CP1
on the RF unit.
• Receiving
• Set the receiver to [B-BAND] and FM mode.
• Operating frequency
: 145.100 MHz
• Connect an SSG to the antenna connector and set as
Level
: 1 mV* (–47 dBm)
Frequency
: 145.100 MHz
Modulation
: OFF
• Connect the Digital multimeter to the check point CP11
on the RF unit.
• Receiving
• Connect the frequency counter to the check point on
the LOGIC unit (See page 5-3).
• Receiving
• Connect the frequency counter to the check point on
the LOGIC unit (See page 5-3).
• Receiving
• Connect the frequency counter to the check point on
the LOGIC unit (See page 5-3).
• Receiving
• Connect an SSG to the antenna connector and set as
Frequency
: 14.0990 MHz
Modulation
: OFF
• Receiving
• Set an SSG as
Level
:
A
+ 35 dB
Frequency
: 14.1005 MHz
Modulation
: OFF
• Receiving
• Connect an SSG to the antenna connector and set as
Frequency
: 14.1010 MHz
Modulation
: OFF
• Receiving
• Set an SSG as
Level
:
A
+ 35 dB
Frequency
: 14.0995 MHz
Modulation
: OFF
• Receiving
• Rotate
[R-DIAL]
to set to 247.05000 MHz.
• Push
[• LOCK]
key.
• Adjust L21 to CP1 voltage to be 1.0 V.
• Adjust L105 to CP11 voltage to be 1.0 V.
• Rotate
[R-DIAL]
to set to 448.5 kHz.
• Push
[• LOCK]
key.
• Rotate
[R-DIAL]
to set to 451.5 kHz.
• Push
[• LOCK]
key.
• Rotate
[R-DIAL]
to set to 449.2 kHz.
• Push
[• LOCK]
key.
• Set an SSG’s level to 10 dB S/N sensitivity (
A
).
• Measure the AF output level while the IC-R20
outputs 1 kHz signal (
B
).
• Measure the AF output level (
C
).
• If AF output level
C
is lower than
B
, skip this
adjustment.
• If AF output level
C
is higher than
B
, rotate
[R-DIAL]
to adjust the AF output level to the same
level as
B
.
• Push
[• LOCK]
key.
• Set an SSG’s level to 10 dB S/N sensitivity (
A
).
• Measure the AF output level while the IC-R20
outputs 1 kHz signal (
B
).
• Measure the AF output level (
C
).
• If AF output level
C
is lower than
B
, skip this
adjustment.
• If AF output level
C
is higher than
B
, rotate
[R-DIAL]
to adjust the AF output level to the same
level as
B
.
• Push
[• LOCK]
key.
ADJUSTMENT
ADJUSTMENT CONDITION
OPERATION
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit.