Panasonic SA-HT990E, Service Manual

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make adjustment if there is a noticeable degradation in picture quality. Optical adjustments
cannot be made inside the optical pickup. Adjustment is generally unnecessary after replacing
the traverse unit.
12.2.2. Important points in electrical adjustment
- Follow the adjustment procedures described in this manual.
12.3. Storing and handling of test discs
- Surface precision is vital for DVD test discs. Be sure to store and
handle them carefully.
1. Do not place discs directly onto the workbench, etc., after use.
2. Handle discs carefully in order to maintain their flatness. Place
them into their case after use and store them vertically. Store
discs in a cool place where they are not exposed to direct sunlight
or air from air conditioners.
3. Accurate adjustment will not be possible if the disc is warped
when placed on a surface made of glass, etc. If this happens, use
a new test disc to make optical adjustments.
4. If adjustment is done using a warped disc, the adjustment will be
incorrect and some discs will not be playable.
12.4. Optical adjustment
12.4.1. Optical pickup tilt adjustment
Measurement point Adjustment point Mode Disc
Tangential adjustment
screw
Tilt adjustment screw
T01 (inner periphery) play
T30 (center periphery)
T43 (outer periphery) play
DVDT-S20 [SPG]
Measuring equipment Adjustment value
None (Main unit display for servicing is used.) Adjust to the minimum jitter value.
12.4.1.1. Adjustment procedure
1. While pressing STOP button on the main unit, press "5" on the
remote control unit.
2. Confirm that "J_xxx/yyy_zz" (display1/display2) is shown on the
front display.
For your information:
"yyy" and "zz" shown to the right have nothing to do with the jitter value. "yyy" is the error
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