Daewoo DV-K784N-JJ, Руководство по обслуживанию, Страница: 31 / 128

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ADJUSTMENT PROCEDURES
1. Rough adjustment of S&T Guide Rollers
When the parts shown in Fig. 9 are substituted, Tape Path can
change. To prevent this, refer to the following instructions.
1). Play back a T-120 tape.
2). Confirm that the excessive tape wrinkle does not occur at
each guide.
3). If tape wrinkle is observed at the guide rollers in Fig. 10, turn
the S&T Guide Rollers for no wrinkle.
2. Pre-adjustment of AC Head Ass'y
1). Tilt Adjustment
a. Play back a T-120 tape and observe the tape running con-
dition at the upper and lower Flanges of T-Guide Post
Ass'y
1
in Fig. 9.
b. Rotate the AC Head Tilt Screw until tape running condi-
tion is optimized (Fig. 10 & 11).
3. Audio Azimuth Adjustment
1). Play back the Alignment Tape (SP mode) with the following
signal.
NTSC: 7KHz PAL: 6KHz
2). Observe the audio output signal appearing on the
Oscilloscope.
3). Turn AC Head Azimuth Screw so that Maximum audio out-
put signal is obtained.
4. AC Head Height Adjustment
1). Play back a T-120 tape.
2). Confirm that the gap between the lower edge of the tape and
the edge of the AC Head is 0.25 mm.
3).If the measure gap exceeds 0.25 mm, turn the AC Head
Height Screw CCW. If not, turn it CW. Repeat this process
until the measuring meets the specification.
5. X-Axis Position Adjustment (Fig. 12 & 13)
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 the Flat Blade Screwdriver, adjust the X-Axis Position
by turning Adjust Boss (Fig. 11) to obtain the maximum
envelope.
NOTE:
Before performing this adjustment, be sure to remove locking
paint applied to the Adjust Boss.
Fig. 10 Tilt Adjustment
0.2± 0.05 mm
TAPE
Fig. 12 AC Head Height Adjustment
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Fig. 11 AC Head Ass'y Identification