Panasonic RX-DT505 Service Manual page 30

RX-DT505
2. The servo processor IC MN6650 of the newly-developed digital servo circuit automatically performs the following adjustments which were
originally adjusted in the conventional analog servo circuit:
(1) Focus offset, (2) Tracking offset, (3) Focus gain, (4) Tracking gain, and (5) Tracking balance. Therefore, you do not have to perform
not the above-mentioned electrical adjustments manually. Only the best eye (PD balance) needs tc be adjusted adjustment. You can obtain
an optimum servo control for a disc to be played.
[You must perform the best eye (PD balance) adjustment manually.]
The following flow chart shows the sequence of automatic adjustments.
Flow chart on automatic adjustment sequence
START
Focus search operation: ON
Focus offset adjustment
Tracking offset adjustment Because the microcomputer precisely performs
automatic adjustments as shown in the flow chart,
it will take approx. 5 seconds to finish reading TOC
data if a used disc is eccentric one or its surface is
Temporary adjustment of focus gain warped.
Spindle motor starts rotation
No
Does focus pull in? Approx. 2.5 sec.
Yes
Focus servo operation: ON
Tracking servo operation: ON
Temporary adjustment of tracking gain
Tracking balance adjustment |
Does tracking pull in?
No
Yes
Fine adjustment of focus gain
Fine adjustment tracking gain
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