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27
HCD-NXM4D
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1dB of peak.
3. Mode: Playback
4. After the adjustments, apply suitable locking compound to
the pats adjusted.
Adjustment Location:
Playback Head (Deck A).
Record/Playback/Erase Head (Deck B).
Screw
position
L-CH
peak
within
1dB
Output
level
L-CH
peak
R-CH
peak
within
1dB
Screw
position
R-CH
peak
MAIN
board
CN301
set
test tape
P-4-A100
(10 kHz, –10 dB)
pin
3
oscilloscope
L-CH
R-CH
V
H
waveform of oscilloscope
in phase 45
°
90
°
135
°
180
°
good
wrong
pin
2
pin
1
L
R
forward
reverse
VIDEO SECTION
Note :
1. DBM07 board is basically designed to operate without adjust-
ment. Therefore, check each item in order given.
2. Use DVD reference disc unless othermise indicated.
[DVD reference disc]
• LUV-P01 (4-999-032-01) (CD)
•TDV-540C (J-2501-235-A) (DVD-DL)
• TDV-520CSO (J-2501-236-A) (DVD-SL)
3. Use an oscilloscope with more than 10M
Ω
impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
Video Level Check (DBM07 BOARD)
Purpose
This adjustment is made to satisfy the NTSC standard, and if not
adjusted correctly, the brightness will be too large or small.
Procedure:
1. Connect oscilloscope to VIDEO output.
2. Load a DVD reference disc playback.
3. Check the video signal level is 1.00
±
0.05Vp-p.
J1102
VIDEO OUTPUT
75
Ω
Oscilloscope
set
1.00
±
0.05 Vp-p
(WHITE 100%)
RE-ADJUSTMENT OF THE SERVO CIRUIT
The re-adjustment of the servo circuit is necessary when
the part which relates to the servo circuit is replaced.
Referring to “1. DRIVE AUTO ADJUSTMENT” (see page 20).
Choose ALL and do the re-adjustment of each item of
DVD-SL, CD and DVD-DL.
THE PART THAT THE RE-ADJUSTMENT OF THE SERVO
CIRCUIT IS NECESSARY.
1. Optical pick-up
2. RF AMP (IC001)
3. DSP IC (IC509)
4. Motor driver IC (IC501)
5. EEPROM (IC204)
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