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SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety checks 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
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” indication
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 battery operated
digital multimeters that have a 2V AC range are suitable. (See
Fig. A)
To Exposed Metal
Parts on Set
0.15
µ
F
1.5 k
Ω
AC
Voltmeter
(0.75 V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
TABLE OF CONTENTS
1. GENERAL
.......................................................................... 4
2. DISASSEMBLY
2-1.
Upper Cover and CD Door ................................................. 5
2-2.
Front Panel ......................................................................... 5
2-3.
Main Board ......................................................................... 6
2-4.
Amp Board ......................................................................... 6
2-5.
CD Tray .............................................................................. 7
2-6.
CD Decoder Board ............................................................. 7
2-7.
Base Unit ............................................................................ 8
2-8.
Cassette Door ..................................................................... 8
3. MECHANICAL ADJUSTMENTS
............................... 9
4. ELECTRICAL ADJUSTMENTS
................................. 9
5. DIAGRAMS
5-1.
Circuit Boards Location ................................................... 14
5-2.
Block Diagrams
• Deck Section ................................................................... 15
• CD Section ...................................................................... 17
5-3.
IC Block Diagrams ........................................................... 19
5-4.
Printed Wiring Board —CD Section — ........................... 24
5-5.
Schematic Diagram — CD Section — ............................. 29
5-6.
Schematic Diagram —Panel Section — .......................... 33
5-7.
Printed Wiring Board —Panel Section — ........................ 37
5-8.
Printed Wiring Board — Deck Section — ....................... 42
5-9.
Schematic Diagram —Deck Section — ........................... 47
5-10. Schematic Diagram —Main Section — ........................... 51
5-11. Printed Wiring Board —Main Section — ........................ 55
5-12. Printed Wiring Board — Amp Section — ........................ 60
5-13. IC Pin Function ................................................................ 65
6. EXPLODED VIEWS
6-1.
Cabinet Section ................................................................. 67
6-2.
Front Panel Section .......................................................... 68
6-3.
Cassette Mechanism Deck Section ................................... 69
6-4.
CD Mechanism Deck Section 1 ....................................... 70
6-5.
CD Mechanism Deck Section 2 ....................................... 71
6-6.
Base Unit Section (KSM-213BCM) ................................. 72
7. ELECTRICAL PARTS LIST
........................................ 73
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