2
TA-SB500WR2
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE
WITH MARK 0ON 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.
Notes on chip component replacement
•Never reuse a disconnected chip component.
•Notice that the minus side of a tantalum capacitor may be
damaged by heat.
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 viscou-s (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 CHECK-OUT
After correcting the original service problem, perform the following
safety check before releasing the set to the customer:
Checktheantennaterminals,metaltrim,“metallized”knobs,screws,
and all other exposed metal parts forAC 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 microamperes.).
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-operatedAC 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 orbattery-operatedAC voltmeter.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 2VAC range are suitable. (See
Fig. A)
Fig. A. Using an AC voltmeter to check AC leakage.
1.5 k
Ω
0.15 µFAC
voltmeter
(0.75 V)
To Exposed Metal
Parts on Set
Earth Ground
TABLE OF CONTENTS
1. GENERAL ................................................................... 3
2. DISASSEMBLY
2-1. Disassembly Flow ........................................................... 4
2-2. Wire Cover ...................................................................... 4
2-3. Top Panel ......................................................................... 5
2-4. Side Panel, Front Panel Block ......................................... 5
2-5. DIAT POWER Board ...................................................... 6
2-6. DIAT AMP Board............................................................ 6
3. DIAGRAMS
3-1. Block Diagram ................................................................ 7
3-2. Printed Wiring Board – DIAT AMP Section (1/2) – ....... 9
3-3. Printed Wiring Boards – DIAT AMP Section (2/2) –...... 10
3-4. Schematic Diagram – DIAT AMP Section (1/4) – .......... 11
3-5. Schematic Diagram – DIAT AMP Section (2/4) – .......... 12
3-6. Schematic Diagram – DIAT AMP Section (3/4) – .......... 13
3-7. Schematic Diagram – DIAT AMP Section (4/4) – .......... 14
3-8. Printed Wiring Boards – POWER SUPPLY Section –.... 15
3-9. Schematic Diagram – POWER SUPPLY Section – ........ 16
4. EXPLODED VIEWS
4-1. Panel Section ................................................................... 23
4-2. DIAT AMP/DIAT POWER Boards Section .................... 24
5. ELECTRICAL PARTS LIST................................ 25