Sony CDP-CX225, Service Manual

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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.
SAFETY-RELATED COMPONENT WARNING !!
COMPONENTS IDENTIFIED BY MARK ! OR DOTTED LINE
WITH MARK ! 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
(US model only)
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
return to chassis, must not exceed 0.5 mA (500 microampers). Leak-
age current can be measured by any one of three methods.
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. 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 battery-operated AC voltmeter. The “limit” indication is 0.75
V, so analog meters must have an accurate low-voltage 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)
NOTES ON HANDLING THE 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, observe
from more than 30 cm away from the objective lens.
LASER DIODE AND FOCUS SEARCH OPERATION CHECK
Carry out the “S curve check” in “CD section adjustment” and check
that the S curve waveform is output repeatedly.
SECTION 1
SERVICING NOTE
Fig. A. Using an AC voltmeter to check AC leakage.
To Exposed Metal
Parts on Set
0.15µF
1.5k
Ω
AC
voltmeter
(0.75V)
Earth Ground