Leakage Test - Sony HCD-F50 Service Manual

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CAUTION
Use of controls or adjustments or performance of
procedures other than those specified herein may
result in hazardous radiation exposure.
This appliance is classified as a CLASS 1 LASER product.
The CLASS 1 LASER PRODUCT MARKING is located on
the rear exterior.
Laser component in this product is capable of emitting radiation
exceeding the limit for Class 1.
The following caution label is located inside the unit.
TE
L 13942296513
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
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SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.
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After correcting the original service problem, perform the follow-
ing 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
return 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
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" indica-
tion is 0.75 V, so analog meters must have an accurate low-
voltage scale. The Simpson 250 and Sanwa SH-63Trd are ex-
amples of a passive VOM that is suitable. Nearly all battery
operated digital multimeters that have a 2 V AC range are suit-
able. (See Fig. A)
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3 6 7 1 3 1 5
0.15 µ F
Fig. A. Using an AC voltmeter to check AC leakage.
ATTENTION AU COMPOSANT AYANT RAPPORT
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 COM-
POSANTS QUE PAR DES PIÈCES SONY DONT LES
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NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.
.
– 3 –
9 4 2 8
SAFETY CHECK-OUT
To Exposed Metal
Parts on Set
0 5 8 2 9 9 4 2 8
1.5 k Ω
Earth Ground
À LA SÉCURITÉ!
m
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AC
voltmeter
(0.75 V)