Servicing Notes - Sony HCD-S20 Service Manual

NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT
The laser diode in the optical pick-up block may suffer electro-
static break-down because of the potential difference generated by
the charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also
use the procedure in the printed matter which is included in the
repair parts.
The fl exible board is easily damaged and should be handled with
care.
NOTES ON LASER DIODE EMISSION CHECK
The laser beam on this model is concentrated so as to be focused
on the disc refl ective surface by the objective lens in the optical
pickup block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.
UNLEADED SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with
the lead free mark due to their particular size)
: LEAD FREE MARK
Unleaded solder has the following characteristics.
• Unleaded solder melts at a temperature about 40 °C higher
than ordinary solder.
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to
about 350 °C.
Caution: The printed pattern (copper foil) may peel away if
the heated tip is applied for too long, so be careful!
• Strong viscosity
Unleaded solder is more viscous (sticky, less prone to fl ow)
than ordinary solder so use caution not to let solder bridges
occur such as on IC pins, etc.
• Usable with ordinary solder
It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.
ABOUT PART REPAIR OF EACH BOARD
The part that mounted on each board cannot exchange. When the
mounted part is damaged, exchange with the complete mounted
board or part including complete mounted board.
Printed wiring board and schematic diagram that have been de-
scribed on this service manual are for reference.
TEST DISCS
Use following TEST DISC (for CD) when this unit confi rms the
operation and checks it.
Part No. Description
3-702-101-01 DISC (YEDS-18), TEST
4-225-203-01 DISC (PATD-012), TEST
SECTION 1

SERVICING NOTES

RELEASING THE DISC TRAY LOCK
The disc tray lock function for the antitheft of sample disc in the
shop is equipped.
Releasing Procedure:
1. Press the [
2. Press two buttons of the [x] on the remote commander and
[Z] on the main unit simultaneously for fi ve seconds.
3. The message "UNLOCKED" is displayed on the fluorescent
indicator tube and the disc tray is unlocked.
Note: When "LOCKED" is displayed, the disc tray lock is not released by
turning power on/off with the [ ?/1 ] button.
CAPACITOR ELECTRICAL DISCHARGE PROCESSING
When checking the board, the electrical discharge is necessary for
the electric shock prevention.
Connect the resistor to both ends of respective capacitors.
• POWER Board
CE501, CE502, CE534
] button to turn the power on.
?/1
– POWER Board (Conductor Side) –
800 /2 W
(for CE501)
800 /2 W
(for CE502)
800 /2 W
(for CE534)
HCD-S20
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