CFD-131 - Sony Audio Service Manual (repair manual). Page 3

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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.
To Exposed Metal
Parts on Set
0.15µF
1.5k
AC
voltmeter
(0.75V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
SAFETY  CHECK-OUT
After correcting the original service problem, perform the following
safety check 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 TEST
The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a re-
turn to chassis, must not exceed 0.5 mA (500 microampers).
Leakage 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 digi-
tal 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 passive VOM
that is suitable. Nearly all battery operated digital multimeters that
have a 2V AC range are suitable. (See Fig. A)
LASER DIODE AND FOCUS SEARCH OPERATION CHECK
1. Open the lid for CD.
2. Push on PUSH SWITCH (S603) as following figure.
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.
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.
S603
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