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22
HCD-GN77D
VIDEO SECTION
Note :
1. VIDEO 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 (VIDEO BOARD)
Purpose
This adjustment is made to satisfy the NTSC standard, and if not
adjusted correctly, the brightness will be too large or small.
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
SUPPLEMENT-1 “1. DRIVE AUTO ADJUSTMENT”
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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