2
XDR-S3HD
SERVICE NOTES
Notes on Chip Component Replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
z
UNLEADED SOLDER
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 higher than
ordinary solder.
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 350°C.
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.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK
0
OR DOTTED LINE
WITH MARK
0
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.
TABLE OF CONTENTS
1. GENERAL
........................................................................... 3
2. DISASSEMBLY
2-1. Panel (Front) Assy ............................................................... 6
2-2. DC Fan (M950) ................................................................... 7
2-3. Wires ................................................................................... 7
2-4. Chassis Assy ........................................................................ 8
2-5. MAIN Board ....................................................................... 8
2-6. POWER Board .................................................................... 9
2-7. KEY Board .......................................................................... 9
2-8. VOL Board, TUNE Board ................................................ 10
2-9. Assembly of the Power Cord ............................................ 10
3. DIAGRAMS
3-1. Block Diagram .................................................................. 11
3-2. Printed Wiring Board – Main Section – ............................ 13
3-3. Schematic Diagram – Main Section – ............................... 14
3-4. Printed Wiring Boards – Power Section – ......................... 15
3-5. Schematic Diagram – Power Section – ............................. 16
3-6. Printed Wiring Board – Micon Section – .......................... 17
3-7. Schematic Diagram – Micon Section – ............................. 18
3-8. Printed Wiring Boards – Key Section – ............................ 19
3-9. Schematic Diagram – Key Section – ................................ 20
4. EXPLODED VIEWS
4-1. Main Section ..................................................................... 25
4-2. Front Panel Section ........................................................... 26
4-3. KEY Board Section ........................................................... 27
4-4. Cabinet Section ................................................................. 28
4-5. Chassis Section ................................................................. 29
5. ELECTRICAL PARTS LIST
........................................ 30
1.5 k
Ω
0.15
µ
F
AC
voltmeter
(0.75 V)
To Exposed Metal
Parts on Set
Earth Ground
SAFETY CHECK-OUT
After correcting the original service problem, perform the fol-
lowing 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
examples of a passive VOM that is suitable. Nearly all bat-
tery operated digital multimeters that have a 2 V AC range
are suitable. (See Fig. A)
Fig. A. Using an AC voltmeter to check AC leakage.
