SAFETY CHECK-OUTTABLE OF CONTENTS
After correcting the original service problem, perform the f1. SERVICING NOollowingTES......................................................... 4
safety check before releasing the set to the customer:
Check the antenna terminals, metal trim, Ometallized� knobs, scr2. GENERALews,
and all other exposed metal parts for AC leakage. ChecLocation of controlsk leakage as................................................................. 5
described below.Adjusting the sound emphasis (MEGA BASS/TONE) ........... 5
Playing a CD ........................................................................... 6
LEAKAGE TESTListening to the radio............................................................... 6
Playing a tape .......................................................................... 7
The AC leakage from any exposed metal part to earth ground andRecording ................................................................................ 7
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microamperes).
3. DISASSEMBLY
Leakage current can be measured by any one of three methods.
3-1. Cabinet (Front) Sub Assy .................................................... 8
3-2. Wires ................................................................................... 9
1. A commercial leakage tester, such as the Simpson 229 or RCA
3-3. Secondary Board, Power Board .......................................... 9
WT-540A. Follow the manufacturersO instructions to use these
3-4. VOL SEL Board ................................................................ 10
instruments.
3-5. Tuner Board....................................................................... 10
3-6. Cabinet (Upper) Assy ........................................................ 11
2. A battery-operated AC milliammeter. The Data Precision 245
3-7. Main Board ....................................................................... 11
digital multimeter is suitable for this job.
3-8. CD Mechanism Block ....................................................... 12
3-9. Tape Mechanism Block ..................................................... 12
3. Measuring the voltage drop across a resistor by means of a VOM
3-10. Holder Assy, Cassette ........................................................ 13
or battery-operated AC voltmeter. The Olimit� indication is 0.75
3-11. PRE Board......................................................................... 13
V, so analog meters must have an accurate low-voltage scale. The
Simpson 250 and Sanwa SH-63Trd are examples of a passive
4. MECHANICAL ADJUSTMENTS...............................14
VOM that is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are suitable. (See Fig. A)
5. ELECTRICAL ADJUSTMENTS
Tape Section .......................................................................... 14
Tuner Section......................................................................... 15
To Exposed MetalCD Section ............................................................................ 16
Parts on Set
6. DIAGRAMS
6-1. IC Pin Description ............................................................. 17
6-2. Circuit Boards Location .................................................... 18
6-3. Block Diagram � CD Section �......................................... 19
AC
0.15?F6-4. Block Diagram � Main Section � ...................................... 211.5k&voltmeter
6-5. Printed Wiring Board � Tuner Section � ........................... 23
(0.75V)
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
Earth Ground
6-10. Printed Wiring Boards � Main Section � .......................... 33
6-11. Schematic Diagram � Main Section (1/2) � ...................... 35
Fig. A. Using an AC voltmeter to check AC leakage.
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. EXPLODED VIEWS
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
� 3 � |
ACEC
