Receiver Adjustments - Icom IC-706MKIIG Service Manual

4-4 RECEIVER ADJUSTMENTS

ADJUSTMENT ADJUSTMENT CONDITION
1 • Display freq.
RECEIVER
• Mode
TOTAL GAIN
• [RIT]
• [M4 AGC]
• [M3 NB]
• [P.AMP/ATT]
• Connect a standard signal genera-
tor to the [ANT1] connector and set
as:
Frequency
Level
Modulation : OFF
• Receiving
2 • [P.AMP/ATT]
• Set an SSG as:
Frequency
Level
Modulation : OFF
• Receiving
WFM 1 • Display freq.
RECEIVING • Mode
• Set an SSG as:
Frequency
Level
Modulation : OFF
• Receiving
1 • Display freq.
NOISE
• Mode
BLANKER
• [P.AMP/ATT]
• [M3 NB]
• R623 (MAIN) : Center
• Connect an SSG to the [ANT1] con-
nector and set as:
Frequency
Level
Modulation : OFF
and apply the following signal to
the [ANT1] connector.
1 msec.
• Receiving
2 • [M3 NB]
• Set an SSG as:
Level
Modulation : OFF
• Receiving
*This output level of the standard signal generator (SSG) is indicated as SSG's open circuit.
: 14.10000 MHz
: USB
: OFF
: Fast (F AGC)
: OFF
: Preamp ON
: 14.10150 MHz
: 0.5 μV* (–113 dBm)
: Preamp OFF
: 14.10150 MHz
: 500 μV* (–53 dBm)
and OFF
: 14.10000 MHz
: WFM
: 14.10000 MHz
: 500 μV* (–53 dBm)
: 14.10000 MHz
: USB
: Preamp ON
: OFF
: 14.1015 MHz
: 18 μV* (–82 dBm)
100 msec.
: ON
: 10 μV* (–87 dBm)
MEASUREMENT
UNIT LOCATION
Rear Connect an AC milli-
Panel voltmeter to the [EXT
SP] jack with an 8 Ω
dummy load.
Rear Connect an AC milli-
Panel voltmeter to the [EXT
SP] jack with a 8 Ω
dummy load.
MAIN Connect a digital
multimeter or oscillo-
scope to check point
CP631.
MAIN Connect an oscillo-
scope to check point
CP632.
4 - 8
ADJUSTMENT
VALUE
UNIT
Muximum AF output MAIN
level
30 dB of AF level differ- MAIN
ence
4.0 V MAIN
Adjust the maximum MAIN
noise wave displayed
on the oscilloscope.
At the point where the MAIN
noise just reduces.
POINT
ADJUST
L731,
L741
R741
L632
L621,
L633
R623