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9. MW IF Adjustment
Requirement:
•
Test point: J203 (SP OUT (LCH,RCH))
•
Adjustment point: L802
1) Set S.S.G. to AM, carrier of 999kHz with 30% modulation, and source at 1kHz.
2) Tune the receiving frequency of the unit at MW 999kHz.
3) While monitoring the waveform at 1kHz through the oscilloscope, lower the output level of S.S.G. maximum.
4) Adjust L802 so that the AC millivoltmeter points maximum.
6. MW Tracking Adjustment
Requirement:
•
Test point: J203 (SP OUT (LCH,RCH))
•
Adjustment point: L952,L953
1) Set S.S.G. to AM, carrier of 999kHz with 30% modulation, source at 1kHz, and output at MAX.
2) Tune the unit to the receiving frequency at MW 999kHz.
3) While monitoring the waveform at 1kHz through the oscilloscope, lower the output level of S.S.G. maximum.
4) Adjust L952 so that the AC millivoltmeter indicates maximum.
5) Set S.S.G. to AM, carrier of 603kHz with 30% modulation, and source at 1kHz.
6) Set the unit to the receiving frequency at MW 603kHz.
7) Adjust L953 so that the AC millivoltmeter indicates maximum.
8) Repeat the above steps 1 to 7 two to three times.
7. LW Tracking Adjustment
Requirement:
•
Test point: J203 (SP OUT (LCH,RCH))
•
Adjustment point: TC942,L941
1) Set up to TC942 to center before adjustment.
2) Set S.S.G. to AM, carrier of 144kHz with 30% modulation, source at 1kHz, and output at MAX.
3) Tune the unit to the receiving frequency at LW 144kHz.
4) While monitoring the waveform at 1kHz through the oscilloscope, lower the output level of S.S.G. maximum.
5) Adjust L941 so that the AC millivoltmeter indicates maximum.
6) Set S.S.G. to AM, carrier of 290kHz with 30% modulation, and source at 1kHz.
7) Set the unit to the receiving frequency at LW 290kHz.
8) Adjust TC942 so that the AC millivoltmeter indicates maximum.
9) Repeat the above steps 2 to 8 two to three times.
8. MW Auto-Stop Check
Requirement:
•
Test point: J203 (SP OUT (LCH,RCH))
1) Set S.S.G. to AM, carrier of 999kHz with 30% modulation, source at 1kHz, and output at 10~70dBuv.
2) Apply the tuning search function, and check that the unit automatically stops at MW 999kHz.
<FM Adjustment>
Make the following preparation for FM adjustment.
Preparation
•
Standard Signal Generator (S.S.G.) / Loop antenna / Oscilloscope / AC millivoltmeter / Dummy resistance (6 ohms)
1) Connect the unit and measuring instruments as shown in the diagram below.
2) Connect the output of S.S.G. to the antenna input of the unit.
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