After correcting the original service problem, perform the following
safety checks before releasing the set to the customer:
1. Check the area of your repair for unsoldered or poorly-soldered
connections. Check the entire board surface for solder splashes
2. Check the interboard wiring to ensure that no wires are “pinched”
or contact high-wattage resistors.
3. Look for unauthorized replacement parts, particularly transistors,
that were installed during a previous repair. Point them out to the
customer and recommend their replacement.
4. Look for parts which, though functioning, show obvious signs of
deterioration. Point them out to the customer and recommend their
5. Check the line cord for cracks and abrasion.
Recommend the replacement of any such line cord to the
6. Check the B+ voltage to see it is at the values specified.
7. Check the antenna terminals, metal trim, “metallized” knobs,
screws, and all other exposed metal parts for AC leakage. Check
leakage as described below.
To Exposed Metal
Parts on Set
Fig.A. Using an Acvoltmeter to check AC leakage.
WHEN SERVICING, DO NOT APPROACH THE LASER EXIT WITH
THE EYE TOO CLOSELY. IN CASE IT IS NECESSARY TO
CONFIRM LASER BEAM EMISSION, BE SURE TO OBSERVE
FROM A DISTANCE OF MORE THAN 25 cm FROM THE SURFACE
OF THE OBJECTIVE LENS ON THE OPTICAL PICK-UP BLOCK.
The use of optical instrument with this product will increase eye
Use of controls or adjustments or performance of procedures other
than those specified herein may result in hazardous radiation
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.
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. A commercial leakage tester, such as the Simpson 229 or RCA
TW-540A. Follow the manufacturers’ instructions to use these
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 volmeter. The “limit” indication is 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 2V AC range are suitable. (See Fig. A)
Boards requiring use of unleaded solder are printed with the lead-free
mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with the
lead free mark due to their particular size.)
: LEAD FREE MARK
Unleaded solder has the following characteristics.
• Unleaded solder melts at a temperature about 40°C highter than
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to about
Caution: The printed pattern (copper foil) may peel away if the
heated tip is applied for too long, so be careful!
• Strong viscosity
Unleaded solder is more viscous (sticky, less prone to flow) than
ordinary solder so use caution not to let solder bridges occur such
as on IC pins, etc.
• Usable with ordinary solder
It is best to use only unleaded solder but unleaded solder may also
be added to ordinary solder.
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFÉS 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 PIÈSES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.