A730 CD Player
Studer is a registered trade mark of Studer Professional Audio AG, Regensdorf
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Electrical Adjustments
•
Plug the two flat cables and the ground lead to their corresponding connectors. Place the front panel with the
new CD drive above the unit’s bottom, using appropriate supports so that the front panel is parallel to its in-
stalled position.
•
Preadjustment:
Turn R23 to its clockwise stop. Laser current is set now to its minimum setting. Turn R33
and R77 to their center positions. Switch the unit on. Verify if the pickup lens moves up and down when ad-
justing R33. If so, set R33 back to its center position. If not, check the wiring of the new cables to the Servo
Board, and also check if the flex PCB is completely plugged into the ZIF connector.
•
Disc Motor Gain:
This setting is fixed now, no adjustment required.
•
Laser Current:
Insert a the “Philips SBC444” test CD (order no. see table below). Close the hinged cover.
Press PLAY repeatedly and adjust R23 counterclockwise until a voltage of 50 ±2 mV can be measured be-
tween TP2 and TP3. If the CD’s table of contents (“TOC”) can be read, two bars appear in the display.
•
Focus Offset:
While the CD is playing, adjust the voltage between TP7 and TP25 to 0 ±5 mV with R33. Tip:
The thickness of the inserted disc has a crucial influence on the focus offset adjustment and refers to a
nominal disc thickness of 1.23 mm. The Philips SBC444 test disc fulfills this specification.
•
Radial Offset:
Insert the “Vérany Digital Test #2” test CD (order no. see table below). Play track 38 and ad-
just with R77 the reproduced sine-wave to minimum dropouts.
Workaround:
If neither the Vérany nor the Philips test CDs are available, set R77 to a
position corresponding to “01:30” on a clock dial (no matter whether AM or PM), as
shown at the right.
•
The upgrade is terminated now, the CD player can be reassembled.
Transport Lock
The new CD drive has a mechanical transport lock. Before trans-
porting the unit, two Allen screws (key no. 2.5) must be released
(approx. 10 turns
counterclockwise
). If so, the drive is fixed in a de-
fined position.
These screws must be tightened (approx. 10 turns
clockwise
) be-
fore the unit is put into operation again.
Test CDs
Type
Studer order no.
Philips SBC444 and SBC444 A
10.241.026.01
Vérany Digital Test #1 and #2
10.693.001.00
Prepared and edited by:
Copyright by Studer Professional Audio AG
Studer Professional Audio AG
Printed in Switzerland
Technical Documentation
Order no. 10.27.4166 (Ed. 1100)
Althardstrasse 30
CH-8105 Regensdorf – Switzerland
Subject to change
unlock
lock
unlock
lock
Laser
pickup
