Sharp 27DV-S100 Service Manual page 21

Ë MTS ADJUSTMENT
MTS Level Adjustment (for TV tuner)
1. Receive the following monaural signal. Monaural
signal: 300Hz, 245mVrms.
2. Connect the rms voltmeter to pin (39) of IC3001.
3. Enter the service mode and select "INPUT LEVEL".
4. Adjust the data so that the rms voltmeter reads 490
+10/-10mVrms.
MTS VCO Adjustment (for TV tuner)
1. Keep the unit in no-signal state.
2. Connect the frequency counter to pin (39) of IC3001.
3. Connect a capacitor (100uF, 50V) between positive
(+) side of C3005 and ground.
4. Enter the service mode and select "MTS VCO".
5. Adjust the data so that the frequency counter reads
62.94 +0.72/-0.75kHz.
Filter Adjustment (for TV tuner)
1. Feed the following stereo pilot signal to pin (14) of
IC3001. Stereo pilot signal: 9.4kHz, 600mVrms.
2. Enter the service mode and select "FILTER".
3. Adjust the data until "OK" appears in position on the
screen. Make sure the "OK" is displayed almost at
the center of the data range.
Separation Adjustment (for TV tuner)
1. Connect the rms voltmeter to pin (39) of IC3001.
2. Receive the following composite stereo signal 1.
Composite stereo signal: 30% modulation, left
channel only, noise reduction on, 300Hz.
3. Enter the service mode and select "WIDE BAND".
4. Adjust the data until the AC voltage reading of the
rms voltmeter is minimum.
5. Receive the following composite stereo signal 2.
Stereo signal: 30% modulation, left channel ony,
noise reduction on, 3kHz.
6. Enter the service mode and select "SPECTRAL".
7. Adjust the data until the AC voltage reading of the
rms voltmeter is minimum.
8. Take the above steps 1 thru 7 again for fine
adjustment.
MTS Level Adjustment (for VCR tuner)
1. Receive the following monaural signal. Monaural
signal: 300Hz, 245mVrms.
2. Connect the rms voltmeter to pin (22) of IC3601 (or
negative (-) side of C1321).
3. Adjust R3614 to become the output level as 490
+10/-10mVrms.
Separation Adjustment (for VCR tuner)
1. Connect the rms voltmeter to pin (22) of IC3601 (or
negative (-) side of C1321).
2. Receive the following composite stereo signal 1.
Composite stereo signal: 30% modulation, left
channel only, noise reduction on, 300Hz.
3. Adjust R3601 to become the output level as the
minimum.
4. Receive the following composite stereo signal 2.
Stereo signal: 30% modulation, left channel only ,
noise reduction on, 3kHz.
5. Adjust R3612 to become the output level as the
minimum.
6. Take the above steps 1 thru 5 again for fine
adjustment.
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27DV-S100
27DV-CS10