Sansui SC 2000 Service Manual

Page 1

SERVICE MANUAL

STEREO CASSETTE TAPE DECK

8All8lll 80-2000
80-2002
80-3000
80-3003

Page 2

This service manual is designed for service engineers to repair, adjust,
maintain and order the replacement parts of the 502000, SC-2002,
SC-3000, SC-3003 correctly.

When ordering the parts, use the stock number and parts name speci-
fically referring to the Parts Location and Parts Lists.

For general usage and maintenance of the unit, please refer to the
Operating Instructions attached with the unit,

TABLE OF CONTENTS

Section Title Page
1. SPECIFICATIONS .................................................. 2
2. BLOCK DIAGRAM. ................. 2

3. ADJUSTMENTS ........................................
3-1. Tape Speed Adjustment ,,,,,,,,
3-2, Playback Adjustment ...........
3-3. Recording Adjustment ........

4. TROUBLESHOOTING CHART .........

5. PARTS LOCATIONS AND PARTS LIST
S-T (3-1197 Main Circuit Board ..........
5-2. (3-1198 Power Circuit Board .,

5-3, (1-1199 Shut-off Circuit Board ...........................
5-4. (3-1200 LED. Circuit Board ............................. 9
5-5. 6-1201 Switch Circuit Board ........................... 9
5-6. (3-1211 LED» Circuit Board ...................................... 9
5-7. 6-1212 Switch Circuit Board .................................... 9
5-8. Figures ........................................................ 9
6. DISASSEMBLY WITH EXPLODED VIEWS AND PARTS LIST ...... 10
6-1. Hardware Nomenclature ...................................... 10
6-2. Disassembly of the Chassis Section .................. .. 11, 12
6-3. Disassembly of the Mechanism Assy ........................ 13, 14

<> Faking List .......................
OAccessory Parts List .................

7. OPERATION OF MECHANISM .............
7-1. Driving Mechanism .....................
7-2, Forward Mode .......................

7-3. REC Mode .. ........................
7-4. Fast Forward and Rewind Operation .
7-5. Pause Mode .......................

8. SCHEMATIC DIAGRAM ..........................................
8-1. 502000, SC-2002 Schematic Diagram ............................ 17
8-2. SC-3000, SC-3003 Schematic Diagram . 18

9. REPLACEMENT OF MAIN PARTS ..... 19
9-1. Replacement of Mechanism Assy ..... 19

9-2, Replacement of Cassette Assy ................................. 19
9~3. Rep|acement of Cassette well and Cassette lid .................... 19

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TRANSPORT MECHANISM SECTION

1. No Tape Running or Tape Speed not Normal

YES

2. Abnormal Playback Sound

3. Each button inoperative

Does tape run smoothly in PLAY mode?

N0

H

Does capstan rotate normally? YES

NO

1. Capstan belt off or slipping
2. Metal bearing burned out

Flywheel
MMetal Bearlnz

3. Defective motor

ls Pinch roller pressure to
tape correct?

N0

NO

Hiya ls take-up torque proper ?

1. PAUSE button keeps ON 1.
2i Pinch roller spring off

Does tape run smoothly in FF & REW mode?-|

N0

3i

Capstan belt slipping around
tension pulley

2. Weak tension of roller arm spring

Improper back tension

Do FR idler and idler (B) rotate normally?

|£>LAre FF & REW torques proper? l-V-Ei4 Is tape itself faulty?

I

N0

NO

NO

2, Shaft of FR idler burned out

1, Weak FR idler pressure to reel hub

1. FR idler excessively slipping
2. Improper back tension

1 Threading tape
2. lrreqular tape winding

l Does the deck playback recorded Tape normally? I

N0

Lls tape speed correct? (See Tape Speed Adj.)

NO

. Incorrect pinch roller pressure
. Excessive back tension
l Takeup torque inocrrect

Jenner--

or pinchroller

l Running tape slips due to dirty around capstan

lls PLAY button mechanism normal?

NO

YES

in cassette case

YES Are wow and flutter

caused in running tape?

N0

. Unstable take-up

#wNI-t

l Tape path compo

, Defective pinch roller or out of oil

l Excessive back tension

torque

nents or belt dirty

Can tape be taken out?
NO

lls PLAY button locked?

7

Does EJECT button Properly operate? I

NO

I: Control button lever for PLAY is not locked]

NO

1. Improper Spring tension
2. Defecive EJECT Iever

or the spring ofi