Icom IC-R7000 Service Manual page 27

6·4 RECEIVER ADJUSTMENT
INSTRUMENTS REQUIRED CONNECTIONS
(1) VOLTMETER
•INPUT IMPEDANCE : 50kn/V DC OR BETTER SSG
(2) SIGNAL GENERATOR (SSG)
TO R140, R139, 051, 050
VOLTMETER
• FREQUENCY RANGE : 0.1 MHz-1 GHz
!
!
TO ANTENNA
•OUTPUT VOLTAGE : 0.1µV-32mV
CONNECTOR
(-127dBm--17dBm)
(3) AC MILLIVOLTMETER
• MEASURING RANGE
: 1omv-1ov
AC
(4) EXTERNAL SPEAKER
MILLIVOLT-
TO [EXT SP]
B
•IMPEDANCE :an
METER
JACK
-
(5) OSCILLOSCOPE
• FREQUENCY RANGE : DC-20MHz
SPEAKER
• MEASURING RANGE : o.01-10v
MEASUREMENT
ADJUSTMENT
POINT
ADJUSTMENT ADJUSTMENT CONDITIONS VALUE
UNIT LOCATION
UNIT ADJUST
BPF 1
•Display freq.: 850.0000MHz RF Connect a
12V RF R90
TRACKING voltmeter to R140.
2 •Display freq.: 999.0000MHz
Approx. 17V Verify
3 •Display freq.: 762.0000MHz Approx. 9.5 V
4 •Display freq.: 650.0000MHz 6.5V R89
5 •Display freq.: 761.0000MHz Approx. 9.5 V
Verify
6
•Display freq.: 513.0000MHz Approx. 3.5 V
7 •Display freq.: 350.0000MHz
RF
Connect a 7.5V RF R79
• R77 (RF UNIT): Center voltmeter to R139.
8 •Display freq.: 511.0000 MHz Approx. 17.5V
Verify
9
• Display freq.: 250.0000 MHz
Approx. 2.2V
10 •Display freq.: 150.0000MHz
RF
Connect a av RF R71
voltmeter to D51.
11 •Display freq.: 90.0000MHz 1V R73
12 •Display freq.: 249.0000MHz Approx. 17.5V
Verify
NOTE: Repeat steps 10, 11 and 12 several times.
13 • Display freq.: 55.0000 MHz
RF
Connect a 6V RF R68
• R66 (RF UNIT): Center voltmeter to D50.
14 • Display freq.: 89.0000 MHz Approx. 9.5 V
Verify
15 •Display freq.: 25.0000MHz Approx. 3V
IF GAIN 1 •Display freq.: 762.0000MHz
FRONT METER Maximum
RF L57, L58
-
• Mode: FM (narrow) PANEL
2
•Apply RF signal to ANTENNA
IF L4, L14,
CONNECTOR.
L5, L6,
Level: 5.0µV (-93dBm)
L7, LS
-
Dev.: ±3.5kHz
3
Mod.: 1kHz
REAR Connect an AC
Maximum L11
PANEL millivoltmeter to
[EXT SP] JACK with
an an speaker.
NOTE: To prevent noise blanker circuit malfunction, set the core positions of L5 and L6 to equal each other.
FM (wide) 1 • Display freq.: 762.0000 MHz FRONT METER Maximum IF L1
• Mode: FM (wide) PANEL
•Apply RF signal to ANTENNA
CONNECTOR.
Level: 5.0µV (-93dBm)
Dev.: ±3.5kHz
Mod.: 1 kHz
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