Sansui AU 5900 AU 6900 Service Manual

Page 1

SERVICE MANUAL

All-6900
All-7900

STEREO AMPLIFIER
SANSUI All-5900

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1. BLOCK DIAGRAM

_TONE CONTROL

EQUALIZER AMP

Pm aut Maul lrt
AUX l C

AUXZC

Tape Flay 5w

Made 5w
Mutmg 3w
Laudrrzas sw

Protect Speaker

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Phanol@-- i M W _ SPEAKER
PhaMZCOI-i i L i k b OUTPUT
L'CH INPUT § EZYW 5 5 51 2 L's
l 1.1" u t: u I \
7 °__L ... i r: K i quC e {Kass F e E» g; a. 5"??? -<*mi
[915(027 53 L I l $4
Deck? é, ________________________ k Phones
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Deck 195 C 747M AMP ~-REGIILATEII 7sz "015cm,

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1 £ng E: :3 50 AMP- 29V supva surm cincun

Land SW DIN Jack

E

(AU-1900)
TONE CONTROL

Defer:
llZEr" (7n
Tone

Select ®®

Tune SW

High mm
Law Filter

Law Filter
lanelvflltr
High [titer

PREAMAW SW
PRfeMAW SW

1
7m Seleclar T -P Tone Selectar

OLIST 0F CIRCUIT BOARD

fUNCTION OF CIRCUIT BORD Au-sm AU»6900 AU-7900
Equalizer a Regulated Power Supply Circuit Board r-2599 r-2599 #2599
Switching Circuit Board between Pre- and Main-Amp. F4600 F2600 F-2600
Switching Circuit Board for Pick-up Load F-260l F4601 F-2601
Lever Switch Circuit Board F-ZEOZ F-2602 F-2609
Volume & Balance Volume Circuit Board ~ F-2603 F-2603 F-2608
Tone Control Circuit Board F-2604 F1606 F-2610
Filter Unit Circuit Board F'ZEflS F4607 F-26I1
Power Amplifier Circuit Board F-2596 Fr2596 F2596
Earth Circuit Board F4598 F4598 F-2598

TABLE OF CONTENTS

1. BLOCK DIAGRAM .. 1 l 3-16 Figures of Semiconductors.. 9
2. SPECIFICATIONS ..., . 2 3-17. Other Parls . . ., 9, 10
3. PARTS LOCATIO PARTS LIST . . .. . 3 0 COMMON PARTS LISTS FOR
3A1. F-2596 Pcwer AmpIIIIer Circuit Board I . 3 RESISTORS It CAPACITORS ONLV . (Attached)
3-1 F- -2598 Earth Circuit Board ... , 4 I 4. TROUBLESHOOTING CHART .. , .
3-3. F- -2593 Equalizer Circuit Board .. I . 5 . 4-1. Operation Block agram of Power
34 F- 2600 Switching Circuit Board between Amplifier ....... . 11
Pre and Main Amp . 5 4-2, Operation Block Diagram of Power
35. F-ZEOZ Switching Circu Supply 8r Protector Circuit .......... . 11
Pick-up Load ,I s l +1 Troubleshooting of Power Amplifier
3-6. F-ZSOZ Lever Switch Circuit Board ,. . 6 Sectlon ...
3-7. p260; Volume & Balance Volume 4-4. Troubleshooting of Power Supply and
Circuit Board ................................. s Protector Circuii.11
3-Bt F4608 Volume & Balance Volume 5. SCHEMATIC DIAGRAM. 12
Circuit Board . r . . .. 7 5-1. AU-59m. .. 12
3-9. F-2609 Lever Switch Circul . . 7 52. AU-59wu l3
3-) F-2610 Tone Control Circuit Board .. . 7 5-3. AU-7900. 14
3-11. F-2611 Filter Circuit Board ....... . 7 6. ADJUSTMENT 15
3-12. r-zwe Tone Control Circuit Board . . B 6-1 Driver Circuit Board Adjustment 12
3-13. F-2607 Filter Circuit Board . . 8 6- 2 Replacement of power Transistors . 15
3-14, F4604 Tone Control Circuit . . . . . 8 7. PACKING LIST ........... . b cow-r
3-15. F4605 Filter Unit Circuit Board .......... . . B 8. ACCESSORY PARTS LIST . hack cow-r