BOSE 318882-B1 D7 BULL Schematic

SERVICE BULLETIN

Bulletin Part Number: 318882-B1
Product: L1 Compact Portable Line Array System
Subject: Defective diodes from vendor
Disposition: On all L1 Compact systems built before 7/24/09 (DOM 9205)that are sent in for service, replace

Zener diodes Z1, Z2 and Z7 using the following procedure.

Symptom: No symptom or dead unit.
Reason: Defective diode(s) from the part manufacturer may fail prematurely.
Solution: Perform the rework procedure below.

Rework Procedure:

1. Using the disassembly procedures in the service manual, remove the power supply / power amplifier PCB
assembly from the power stand cabinet.

2. Locate and remove zener diodes Z1, Z2 and Z7. Discard.

3. Using Bose part number 325372-001S, replace Z1, Z2 and Z7 with new parts. The diodes are On-Semi
1N5347B, 5W, 10V zener diodes with axial leads. Be sure to observe polarity when inst alling the new part s.

4. Re-install the power supply / power amplifier PCB assembly into the power stand cabinet.

5. Perform the power stand test proce­dures located in the L1 Compact service
manual to ensure proper operation before
returning the system to the customer.

Notes:

1. Refer to the L1 Compact service
manual, 318882-SM, located on the
service web site located at
http://serviceops.bose.com for
disassembly and test procedures.

2. Refer to the board layout diagram at
right and the schematic diagram located
on page 2 of this bulletin for the locations
of Z1, Z2 and Z7 in the circuit and on the
circuit board.

Date Issued: 8/09

Bose Corporation; The Mountain, Framingham, Ma. 01701-9168

Service documentation available online at http://serviceops.bose.com

page 1 of 2

SERVICE BULLETIN

C10100

C13

221

C74

221

R23

10R

C15

47u

/100V

C17

470u

F/35V

C16

470u

F/35V

R33

10R

R44

10R

VDDA

VDDP

+2727V

VSSA

VDDP

VDDP

VSSA

VDDA

VSSA

R54

100

R51

100K

R43

4.7K

C82

104

L14

22UH

Z4

22V

VSSP

-27V

VSSP

VSSP

L18

BEAD

L20

BEAD

C89

104

C90

104

+2727V

-27V

SGND

VSS

VDD

R50

39K

R40

4.7K

Q2

2N

2222

Q1

2N

2222

R58

4.7K

Z5

5.6V

R57

20K

VDDP

C88

104

VDDP

TO

PRE-

AMP S

ECTION

+1818V

-1818V

SGND

L26

BEAD

L19

BEAD

VDD

VSS

1

SCR4

1

SCR2

1

SCR5

1

SCR6

C73

103

C66

103

C67

103

C47

103

C60

103

C49

103

C104

104

C70

104

C18

1000uF/3535V

C12

1000uF/3535V

L25

BEAD

L27

BEAD

VDDP

1

SCR3

VDDP

VSSP

Z2

10V 5W

VDDP

1

SCR1

C56

103

C65

103

C64

103

C40

47uF/1010V

FUS2

0.5A

FUS3

0.5A

R4

20

U1

1

7

1

1

2

V

S

4

TOP258-Y

!

X2G/F

R16

0

D

3

C

5

R17

*

HVN

Z1 and Z7 locations
L1 Compact schematic
section from sheet 1 of 2

R20

0

C42

47pF/1KV

R62

20

R66

10K

Z6

14V

C55

104

Z7

10V 5W

AUX+

R36

50

R37

50

AUX-

D1

BAV21

R63

4.7K

R18

6.8

C4

47uF/10V

104

1000uF/35V

Z3

30V

R27

180

C80

100nF

R30

3.3K

-27V

R28

C109

104

100K

C94

104

R26

20K

R32

402k

R59

100K

C86

100nF

R535

10k

39K

-27V

-27V

VDDP

R38

210k

Z1

10V 5W

VDD

VSS

BEAD

C21

1nF 1KV

D7

LL4148

C27

10uF/50V

L24

U2A

EL817A

1

2

2

3

C38

35V/100uF

C34

35V/100uF

1000uF/35V

R538

4.7K

R31

1K

U4

TL431

1

HS1

1

D4

3

2

1

MUR1640

R39

16

R29

16

!

R25

10k

BEAD

L21

C91

104

C92

104

L22

BEAD

4

3

101

4.7uF/63V

U2B

EL817A

!

C5

!

YC9

!

*

D5

ES1D

R41

C83

50

1nF 250V

R42

C85

50

1nF 250V

D6

AK

ES1D

SGN

TO

C1

1000uF

10

VD

VS

100

VSS

VDD

VDD

VDD

10

222

VSS

BEA

BEA

VDD

47uF

VDD

C4

VSS

VSS

47

/100

10

10

10

VDD

VD

VS

39

VSS

Z1 and Z7 locations
L1 Compact schematic
section from sheet 2 of 2

10

10

10

10

20

VDD

VDD

VSS

22

VSS

22

10

10

10

10

22

page 2 of 2

BEA

C10

C1

10

C7

10

1000uF

222

VDD

10

470

SGN

10

PRE

SCR

SCR

AMP

-2

ECT

BEA

-2

10

10

VDD

SCR

SCR

SCR

SCR

F/35

470

F/35

FUS

BEA

BEA

FUS

10

22

4.7

4.7

Bose Corporation; The Mountain, Framingham, Ma. 01701-9168

Service documentation available online at http://serviceops.bose.com