Aiwa NSX-R50, Руководство по обслуживанию

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<FM Adjustment>
Make sure that the following settings are done before adjustment.
Preparation
* Measuring instruments: Standard Signal Generator (S.S.G.) / Oscilloscope / Millivoltmeter / Dummy resistor (6
Ω )
(1) Connect the measuring instruments as shown in the diagram below.
(2) Connect the output terminal of signal generator to the antenna input terminal of the unit.
DUMMY
SPOUT(L)
AC MILLIVOLTMETER
CH2 CH1
6
Ω
OUTPUT
OSCILLOSCOPE
CH2 CH1
LOAD
SET
Standerd Signal Genertaor
FM ANT
SPOUT(R)
9. Tracking Adjustment
Requirements
* Test Point: SP OUT (Lch, Rch)
(1) Adjust the S.S.G. setting to FM; carrier at 108 MHz, distortion at 75 kHz, and source 1 kHz.
(2) Adjust the unit to FM 75 MHz.
(3) While monitoring 1 kHz waveform through oscilloscope, decrease the S.S.G. output level (till slight noises appear in the
waveform).
(4) Adjust L901, 902, 904 and 905 so that the millivoltmeter indicates the maximum level.
10. Separation Check
Requirements: Same as Item 9.
(1) Adjust the S.S.G. setting to FM; carrier at 83 MHz; distortion at 67.5 kHz; source at 1 kHz, and output at 60 dBuv.
(2) Switch the S.S.G. to PILOT ON, and set to PILOT 7.5 kHz.
(3) Adjust the unit to FM 83 MHz.
(4) Check that S.S.G outputs only from Lch and that the difference between Lch and Rch at that time is 25 dB or above.
(5) Check for Rch in the same manner.
11. Auto-Stop Function Check
Requirements: Same as Item 5.
(1) Adjust the S.S.G. setting to FM; carrier at 108 MHz; distortion at 75 kHz; source at 1 kHz and output at 25 dBuv.
(2) Start the tuning search mode, and check that the auto-stop function is applied at FM 108 MHz.
Standard Signal Generator