–3 –
TABLE OF CONTENTS
1. SERVICING NOTES......................................................... 4
2. GENERAL
Location of controls................................................................. 5
Adjusting the sound emphasis (MEGA BASS/TONE) ........... 5
Playing a CD ........................................................................... 6
Listening to the radio............................................................... 6
Playing a tape .......................................................................... 7
Recording ................................................................................ 7
3. DISASSEMBLY
3-1. Cabinet (Front) Sub Assy .................................................... 8
3-2. Wires ................................................................................... 9
3-3. Secondary Board, Power Board .......................................... 9
3-4. VOL SEL Board ................................................................ 10
3-5. Tuner Board....................................................................... 10
3-6. Cabinet (Upper) Assy ........................................................ 11
3-7. Main Board ....................................................................... 11
3-8. CD Mechanism Block ....................................................... 12
3-9. Tape Mechanism Block ..................................................... 12
3-10. Holder Assy, Cassette ........................................................ 13
3-11. PRE Board......................................................................... 13
4. MECHANICAL ADJUSTMENTS............................... 14
5. ELECTRICAL ADJUSTMENTS
Tape Section .......................................................................... 14
Tuner Section......................................................................... 15
CD Section ............................................................................ 16
6. DIAGRAMS
6-1. IC Pin Description............................................................. 17
6-2. Circuit Boards Location .................................................... 18
6-3. Block Diagram – CD Section –......................................... 19
6-4. Block Diagram – Main Section –...................................... 21
6-5. Printed Wiring Board – Tuner Section – ........................... 23
6-6. Schematic Diagram – Tuner Section – .............................. 25
6-7. Printed Wiring Board – CD Section –............................... 27
6-8. Schematic Diagram – CD Section –.................................. 29
6-9. Schematic Diagram – PRE Section –................................ 31
6-10. Printed Wiring Boards – Main Section – .......................... 33
6-11. Schematic Diagram – Main Section (1/2) – ...................... 35
6-12. Schematic Diagram – Main Section (2/2) – ...................... 37
6-13. Printed Wiring Board – Control Section – ........................ 39
6-14. Schematic Diagram – Control Section – ........................... 41
6-15. Printed Wiring Boards – Power Supply Section – ............ 43
6-16. Schematic Diagram – Power Supply Section –................. 45
7. EXPLODEDVIEWS
7-1. Cabinet (Front) Section ..................................................... 50
7-2. Cabinet (Rear) Section ...................................................... 51
7-3. Cabinet (Upper) Section.................................................... 52
7-4. Tape Mechanism Section-1 ............................................... 54
7-5. Tape Mechanism Section-2 ............................................... 55
7-6. Optical Pick-up Section .................................................... 56
8. ELECTRICAL PARTS LIST......................................... 57
To Exposed Metal
Parts on Set
0.15µF 1.5k
Ω
AC
voltmeter
(0.75V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety check before releasing the set to the customer:
Checkthe antenna terminals,metal trim, “metallized” knobs,screws,
and all other exposed metal parts forAC leakage. Check leakage as
described below.
LEAKAGETEST
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-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 aVOM
or battery-operatedAC 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)