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GF-7850H(D)
©
CIRCUIT ADJUSTMENT (TUNER SECTION)
AM IF/RF
Oscilloscope
SIGNAL
400 Hz, 30%, AM modulated
Sweep
Test
MW/LW
GENERATOR
DIAL
QUENCY | POINTER
SETTING
REMARKS
455 kHz
For UK:
468 kHz
Adjust for
145 kHz
295 kHz | Highest
frequency
Adjust for
170 kHz | 170 kHz
Tracking
220 kHz | 220 kHz
Repeat steps 2,3,4 and 5 until no further improvement can
be made.
MW RF
cai | ats ey
ae
Repeat steps 7,8,9 and 10 until no further improvement
can be made.
|
ena
pon
a
rr
ere
Adjust for
maximal output.
14 | sacking L2SMME |
Repeat steps 12,13,14 and 15 until no further improvement
can be made.
best "'IF'' curve.
maximal output.
7
Lowest
Band
frequency
coverage
1650 kHz]
Highest
frequency
Adjust for
generator
loop _ bar antenna
Figure 12—1
AMIF
455 kHz
Figure 12—2 AMIF CURVE
Electronic
MW/LW
voltmeter
bar antenna
Signal
Test
generator
loop
Figure 12—3 MW RF
Electronic
Dumm
:
voltmeter
(See Figure 12—5)
Signal
Rod Antenna
generator
Figure 12—4 SW RF
}-—= To telescopic rod antenna
Z=50 ohms<
f= ee
Z: Output impedance of signal generator
To chassis GND
Figure 12-5 SW DUMMY
-12—
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