Daewoo DV-K784N-JJ, Service Manual

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10. Audio Output Confirmation (AC Head Tilt/Height
Adjustment
Test Points: Audio Out Audio Out Jack
Observe: Oscilloscope
1). Connect the oscilloscope to the audio output jack on VCR.
2). Playback the 400-1000Hz Audio Alignment Tape.
3).Confirm that the audio output signal is between –8dBm and
–10dBm.
NOTE:
If the audio signal is not within the specification, readjust the
A/C Head Tilt Screw and the A/C Head Height Nut slightly to
maximize the audio output. Refer to Fig. 11 for adjustment
screw location.
11. AC Head Azimuth Adjustment
Test Points: Audio Out Audio Out Jack
Observe: Oscilloscope
1). Connect the oscilloscope to the audio output jack on VCR.
2). Play back the 400-1000Hz Audio Alignment Tape.
3).Adjust the AC Head Azimuth Screw for maximum audio out-
put (specification = –12dBm to 14dBm). Refer to Fig. 11 for
adjustment screw location.
4).After completing the adjustment procedure, reconfirm "Fine
Adjustment of Envelopes at Drum Entrance/Exit Parts".
12. X-Axis Adjustment (Fig. 19)
Test Points: CTL Pulse Test Pin Path Adj. Fixture
Envelope Test Pin Path Adj. Fixture
Observe: Oscilloscope
Adjust: VR Control Path Adj. Fixture
S/T Guide Rollers Transport Mech.
1).Connect the Path Adj. Fixture to PT01 on the Main circuit
board.
2).Play back the Alignment Tape (Color Bar Signal).
3. Connect the channel-1 scope probe to the CTL pulse test pin
on the Path Adj. Fixture.
4).Connect the channel-2 scope probe to the envelope test pin on
the Path Adj. Fixture. Externally trigger the scope using the
SW pulse test pin on the Path. Adj. Fixture.
5).Adjust the VR Control on the Path Adj. Fixture to its center
range position.
6).Using a flat blade screwdriver, adjust the X-Axis Position
Point by turning Adjust Boss so that the envelope waveform
is as shown in Fig. 19 when the VR Control on the Path Adj.
Fixture is turned fully CCW or CW.
7).After completing the adjustment procedure, perform the
"Playback Phase Adjustment".
Fig. 19 X-Axis Adjustment