Sony rcd w 3 service manual

Page 2

RCD-W3

NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electrostatic
breakedown 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 flexible 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 reflective surface by the objective lens in the optical pick
up block. Therefore, when checking the laser diode emission, ob
serve from more than 30 cm away from the objective lens.

The Laser component in this product is capable of emitting
radiation exceeding the limit for Class 1.

This appliance is classified as
a CLASS 1 LASER product.
The CLASS I LASER PRODA
UCT MARKING is located on
the rear exterior.

CLASS 1 LASER PRODUCT
LUOKAN I LASERLAITE

KLASS 1 LASERAPPARAT

CAUTION

Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous ra~
diation exposure.

Notes on chip component replacement

- Never reuse a disconnected chip component.

' Notice that the minus side of a tantalum capacitor may be
damaged by heat.

Flexible Circuit Board Repairing

' Keep the temperature of soldering iron around 270°C
during repairing.

- Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).

' Be careful not to apply force on the conductor when soldering
or unsoldering.

SAFETY-RELATED COMPONENT WARNING !!

COMPONENTS IDENTIFIED BY MARK A OR DOTTED LINE
WITH MARK A ON THE SCHEMATIC DIAGRAMS AND IN
THE PARTS LIST ARE CRITICAL TO SAFE OPERATION.
REPLACE THESE COMPONENTS WITH SONY PARTS
WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS
MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY.

SAFETY CHECK-OUT

After correcting the original service problem, perform the follow-
ing safety checks before releasing the set to the customer:

Check the antenna terminals, metal trim, metallized knobs, screws,
and all other exposed metal parts for AC leakage. Check leakage as
described below.

LEAKAGE

The AC leakage from any exposed metal part to earth Ground and

from all exposed metal parts to any exposed metal part having a

retum to chassis, must not exceed 0.5 mA (500 microampers). Leak-

age current can be measured by any one of three methods.

I. A commercial leakage tester, such as the Simpson 229 or RCA
WT7540A. Follow the manufacturers instructions to use these
instruments.

2. A battery-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a VOM
or batteryeoperated AC voltmeter. The limit" indication is 0.75
V, so analog meters must have an accurate lowAvoltage scale.
The Simpson 250 and Sanwa SH-63Trd are examples of a pas»
sive VOM that is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are suitable. (See Fig. A)

To Exposed Metal
Parts on Set

A C
voltmeter
(0. 75 V)

0. 15uF

{$1.5m
;_|

'5 Earth Ground

Fig. A. Using an AC voltmeter to check AC leakage.

ATTENTION AU COMPOSANT AYANT RAPPORT

A LA SECURITEII
LES COMPOSANTS IDENTIFIES PAR UNE MARoUE ASUFI
LES DIAGRAMMES SCHEMATIQUES ET LA LISTE DES
PIECES SONT CRITIQUES POUR LA SECURITE DE
FONCTIONNEMENT. NE REMPLACER CES COMPOSANTS
QUE PAR DES PIECES SONY DONT LES NUMERos
SONT DONNES DANS CE MANUEL ou DANS LES
SUPPLEMENTS PUBLIES PAR SONY.