6558-03N/03S/43N/43S
SAFETY CHECK-OUT
(US Model only)
After correcting the original service problem, perform the fol-LEAKAGE TEST
lowing safety checks before releasing the set to the customer:The AC leakage from any exposed metal part to earth ground
1. Check the area of your repair for unsoldered or poorly-sol-and from all exposed metal parts to any exposed metal part hav-
dered connections. Check the entire board surface for soldering a return to chassis, must not exceed 0.5 mA (500
splashes and bridges.microampers).
2. Check the interboard wiring to ensure that no wires areLeakage current can be measured by any one of three methods.
Opinched� or contact high-wattage resistors.1. A commercial leakage tester, such as the Simpson 229 or
3. Check that all control knobs, shields, covers, ground straps,RCA WT-540A. Follow the manufacturersO instructions to
and mounting hardware have been replaced. Be absolutelyuse these instruments.
certain that you have replaced all the insulators.2. A battery-operated AC milliammeter. The Data Precision
4. Look for unauthorized replacement parts, particularly tran-245 digital multimeter is suitable for this job.
sistors, that were installed during a previous repair. Point3. Measuring the voltage drop across a resistor by means of a
them out to the customer and recommend their replacement.VOM or battery-operated AC voltmeter. The Olimit� indica-
5. Look for parts which, though functioning, show obvioustion is 0.75 V, so analog meters must have an accurate low-
signs of deterioration. Point them out to the customer andvoltage scale. The Simpson 250 and Sanwa SH-63Trd are
recommend their replacement.examples of a passive VOMs that are suitable. Nearly all
6. Check the line cords for cracks and abrasion. Recommendbattery operated digital multimeters that have a 2 V AC
the replacement of any such line cord to the customer.range are suitable. (See Fig. A)
7. Check the B+ and HV to see if they are specified values.
Make sure your instruments are accurate; be suspicious of WARNING!!
your HV meter if sets always have low HV.NEVER TURN ON THE POWER IN A CONDITION IN
WHICH THE DEGAUSS COIL HAS BEEN REMOVED.
8. Check the antenna terminals, metal trim, Ometallized�
knobs, screws, and all other exposed metal parts for AC
Leakage. Check leakage as described below.SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY SHADING AND MARK
� ON THE SCHEMATIC DIAGRAMS, EXPLODED
To Exposed Metal
Parts on SetVIEWS AND IN THE PARTS LIST ARE CRITICAL FOR
SAFE OPERATION. REPLACE THESE COMPONENTS
WITH SONY PARTS WHOSE PART NUMBERS AP-
PEAR AS SHOWN IN THIS MANUAL OR IN SUPPLE-
MENTS PUBLISHED BY SONY. CIRCUIT ADJUST-
MENTS THAT ARE CRITICAL FOR SAFE OPERATION
AC
0.15 ?F1.5 kWVoltmeterARE IDENTIFIED IN THIS MANUAL. FOLLOW THESE
(0.75 V)
PROCEDURES WHENEVER CRITICAL COMPONENTS
ARE REPLACED OR IMPROPER OPERATION IS SUS-
PECTED.
Earth Ground
AVERTISSEMENT!!
NE JAMAIS METTRE SOUS TENSION QUAND LA
Fig. A. Using an AC voltmeter to check AC leakage.
BOBINE DE DEMAGNETISATION EST ENLEV?E.
ATTENTION AUX COMPOSANTS RELATIFS � LA
S?CURIT?!!
LES COMPOSANTS IDENTIFI?S PAR UNE TRAME ET
UNE MARQUE � SONT CRITIQUES POUR LA S?CURIT?.
NE LES REMPLACER QUE PAR UNE PIéCE PORTANT LE
NUM?RO SPECIFI?. LES R?GLAGES DE CIRCUIT DONT
LOIMPORTANCE EST CRITIQUE POUR LA S?CURIT? DU
FONCTIONNEMENT SONT IDENTIFI?S DANS LE
PR?SENT MANUEL. SUIVRE CES PROC?DURES LORS
DE CHAQUE REMPLACEMENT DE COMPOSANTS CRI-
TIQUES, OU LORSQUOUN MAUVAIS FONCTIONNE-MENT
EST SUSPECT?.
� 2 � |
ACEC
SONY
