– 3 –
NOTES ON HANDLINGTHE OPTICAL PICK-UP BLOCK
OR BASE UNIT
The laser diode in the optical pick-up block may suffer electrostatic
breakdown because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic breakdown 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 more than 30 cm away from the objective lens.
LASER DIODE AND FOCUS SEARCH OPERATION
CHECK
1. Close the lid for CD.
2.Press CD ^button.
3. Confirm the laser diode emission while observing the objecting
lens. When there is no emission, Auto Power Control circuit or
Optical Pick-up is broken.
Objective lens moves up and down once for the focus search.
CAUTION DURINGWHEN MOUNTINGTHE PULLEY
FORTHE LOADING MOTOR
Make the following adjustment when mounting the loading motor
(part number : 1-698-999-11) and motor pulley (part number : 2-
627-174-01) of the CD section.
Specification : A = 0.9 to 1.1mm
SECTION 1
SERVICE NOTE
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK !OR DOTTED LINEWITH
MARK !ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS
LIST ARE CRITICALTO SAFE OPERATION.
REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE
PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN
SUPPLEMENTS PUBLISHED BY SONY.
Flexible Circuit Board Repairing
• Keep the temperature of the 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.
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
SAFETY CHECK-OUT (US Model)
After correcting the original service problem, perform the follow-
ing safety check before releasing the set to the customer :
Checktheantenna terminals,metaltrim, “metallized” knobs,screws,
and all other exposed metal parts forAC leakage. Check leakage as
described below.
LEAKAGETEST
The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5mA (500 microampers).
Leakage current can be measured by any one of three methods.
1. Acommercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers’ instructions to use these
instruments.
2. Abattery-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 aVOM
orbattery-operatedAC voltmeter.The “limit” indicationis 0.75V,
so analog meters must have an accurate low-voltage scale. The
Simpson 250 and Sanwa SH-63Trd are examples of a passive
VOM that is suitable. Nearly all battery operated digital
multimeters that have a 2VAC range are suitable. (See Fig. A)
AC
voltmeter
(0.75V)
To Exposed Metal
Parts on Set
Earth Ground
0.15
µ
F 1.5k
Ω
Fig. A. Using an AC voltmeter to check AC leakage.
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE !SUR LES
DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT
CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS QUE PAR DES PIÈCES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.
