Page 1
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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:
1. Check the area of your repair for unsoldered or poorly-sol-dered
connections. Check the entire board surface for solder splashes
and bridges.
2. Check the interboard wiring to ensure that no wires are pinched
or contact high-wattage resistors.
3. Look for unauthorized replacement parts, particularly transis-
tors, that were installed during a previous repair. Point them out
to the customer and recommend their replacement.
4. Look for parts which, though functioning, show obvious signs
of deterioration. Point them out to the customer and recom-
mend their replacement.
5. Check the line cord for cracks and abrasion. Recommend the
replacement of any such line cord to the customer.
6. Check the B+ voltage to see it is at the values specified.
7. 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 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 a VOM
or battery-operated AC voltmeter. The limit indica-tion is
0.75V, so analog meters must have an accurate low-voltage scale.
The Simpson 250 and Sanwa SH-63Trd are ex-amples of a pas-
sive VOM that is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are suit-able. (See Fig. A)
WARNING!!
WHEN SERVICING, DO NOT APPROACH THE LASER EXIT
WITH THE EYE TOO CLOSELY. IN CASE IT IS NECESSARY
TO CONFIRM LASER BEAM EMISSION, BE SURE TO
OBSERVE FROM A DISTANCE OF MORE THAN 25 cm
FROM THE SURFACE OF THE OBJECTIVE LENS ON THE
OPTICAL PICK-UP BLOCK.
ATTENTION AU COMPOSANT AYANT RAPPORT
Ã- LA SÉCURITÉ!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE
! !! !
! SUR LES
DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT
CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE
REMPLACER CES COM-POSANTS QUE PAR DES PIÈCES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK
! !! !
! 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
PUB-LISHED BY SONY.
CAUTION:
The use of optical instrument with this product will increase eye
hazard.
CLASS 3B LASER
LUOKAN 3B LASER
LASERKLASS 3B
CAUTION
Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous ra-
diation exposure.
To Exposed Metal
Parts on Set
AC
voltmeter
(0.75 V)
Earth Ground 1.5 k-„¦ 0.15 µF
Fig. A. Using an AC voltmeter to check AC leakage.
Page 2
-“ 3 -“ TABLE OF CONTENTS
Section Title Page
1. GENERAL
2. DISASSEMBLY
2-1. Terminal Cover, Lower Case .......................................... 2-1
2-2. Upper Case .................................................................... 2-1
2-3. Mechanism Deck ............................................................ 2-1
2-4. Chucking Arm Block ....................................................... 2-1
2-5. MD-90, Board, Lever Assembly ...................................... 2-2
2-6. Base (C) Assembly ......................................................... 2-2
2-7. Optical Device ................................................................ 2-2
2-8. BU Holder ....................................................................... 2-2
2-9. Gate Assembly, Cover (T) .............................................. 2-3
2-10. Roller (Slider) ................................................................. 2-3
2-11. Slider (L), Slider (R) ........................................................ 2-3
2-12. FL-123 Board ................................................................. 2-3
2-13. MB-99, IR-39 Boards ...................................................... 2-4
2-14. Sliders (L) and (R) Phase Adjustment ............................ 2-4
2-15. Internal Views ................................................................. 2-5
2-16. Circuit Boards Location .................................................. 2-6
3. BLOCK DIAGRAMS
3-1. Overall Block Diagram .................................................... 3-1
3-2. RF/SERVO Block Diagram ............................................. 3-3
3-3. Signal Processor Block Diagram .................................... 3-5
3-4. System Control Block Diagram ...................................... 3-7
3-5. Video Block Diagram ...................................................... 3-9
3-6. Audio Block Diagram .................................................... 3-10
3-7. Interface Control Block Diagram ................................... 3-11
3-8. Power Block Diagram ................................................... 3-12
4. PRINTED WIRING BOARDS AND SCHEMATIC
DIAGRAMS
4-1. Frame Schematic Diagram ............................................. 4-3
4-2. Printed Wiring Boards and Schematic Diagrams ........... 4-5
- IR-39 (IR) Printed Wiring Boards and Schematic
Diagrams .................................................................... 4-5
- MB-99 (VIDEO/AUDIO/SIGNAL PROCESS/SERVO)
Printed Wiring Board .................................................. 4-7
- MB-99 (SYSTEM CONTROL) Schematic
Diagram .................................................................... 4-11
- MB-99 (RF SERVO) Schematic Diagram ................. 4-13
- MB-99 (SIGNAL PROCESS) Schematic Diagram ... 4-15
- MB-99 (SERVO) Schematic Diagram ....................... 4-17
- MB-99 (SIGNAL PROCESS) Schematic Diagram ... 4-19
- MB-99 (SIGNAL PROCESS) Schematic Diagram ... 4-21
- MB-99 (POWER) Schematic Diagram ...................... 4-23
- MB-99 (AV OUT) Schematic Diagram ...................... 4-25
- MB-99 (VIDEO) Schematic Diagram ........................ 4-27
- MB-99 (AUDIO) Schematic Diagram ........................ 4-29
- MB-99 (AVMS) Schematic Diagram ......................... 4-31
- MD-89 (FUNCTION SWITCH 1)
Printed Wiring Board and Schematic Diagram ......... 4-33
- FL-123 (INTERFACE CONTROL)
Printed Wiring Board ................................................ 4-35
- FL-123 (INTERFACE CONTROL)
Schematic Diagram .................................................. 4-37
- MD-90 (FUNCTION SWITCH) Printed Wiring Board
and Schematic Diagram ........................................... 4-39
- MD-91 (SWITCH) Printed Wiring Board and
Schematic Diagram .................................................. 4-39
Section Title Page
5. IC PIN FUNCTION DESCRIPTION
5-1. System Control PIN Function (MB-99 Board IC103) ...... 5-1
5-2. System Control PIN Function (FL-123 Board IC403) ..... 5-2
6. TEST MODE
6-1. General Description ....................................................... 6-1
6-2. Starting Test Mode ......................................................... 6-1
6-3. Syscon Diagnosis ........................................................... 6-1
6-4. Drive Auto Adjustment .................................................... 6-5
6-5. Drive Manual Operation ................................................. 6-7
6-6.Mecha Aging ................................................................ 6-10
6-7.Emergency History ....................................................... 6-10
6-8. Version Information ...................................................... 6-12
6-9. Video Level Adjustment ................................................ 6-12
6-10. IF CON Function Check Mode ..................................... 6-12
6-11. Troubleshooting ............................................................ 6-15
7. ELECTRICAL ADJUSTMENT
7-1. Power Supply Check ...................................................... 7-1
1. MB-99 Boards .......................................................... 7-1
7-2.Adjustment of Video System .......................................... 7-2
1. Video Level Adjustment (MB-99 Board) ................... 7-2
2. Checking S Video Output S-Y .................................. 7-2
3. Checking S Video Output S-C .................................. 7-2
7-3. Adjustment Related Parts Arrangement ......................... 7-2
8. REPAIR PARTS LIST
8-1. Exploded Views .............................................................. 8-1
8-1-1. Case Assembly ............................................................ 8-1
8-1-2. MECH.DECK Block (1) ................................................ 8-2
8-1-3. MECH.DECK Block (2) ................................................ 8-3
8-1-4. CHASSIS Block ........................................................... 8-4
8-1-5. Supplied Accessories .................................................. 8-5
8-2. Electrical Parts List ......................................................... 8-6
