Chapter 2. Adjustments; Servo Section - Sharp HT-DV40H Service Manual

HT-DV40H

CHAPTER 2. ADJUSTMENTS

E Market CD-ES700/CD-ES77 Service Manual CD-ES700/CD-ES77 CD-ES700/CD-ES77

[1] Servo Section

• Adjustment
Since this DVD system incorporates the following
automatic adjustment functions, readjustment is
not needed when replacing the pickup. Therefore,
different PWBs and pickups can be combined
freely. Each time a disc is changed, these
adjustments are
Therefore, playback of each disc can be performed
under optimum conditions.
Items adjusted automatically
1) Offset adjustment (The offset voltage between the
head amplifier output and the VREF reference
voltage is compensated inside the IC.)
* Focus offset adjustment
* Tracking offset adjustment
2) Tracking balance adjustment
3) Gain adjustment (The gain is compensated inside
the IC so that the loop gain at the gain crossover
frequency will be 0 dB.)
* Focus gain adjustment
* Tracking gain adjustment
performed automatically.
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