Laney MXD120 H-Twin Schematic

MXD120/H/Twin

Service InformationService Information

Laney

Classic British Amplification

Newlyn Road, Cradley Heath, West Midlands. B64 6B£

www.laney.co.uk

1

MJACK

G

SK1

GG

A A

B B

Input

C4
4N7 1 00V
R1
10K

R2
1M

G G

+15V

C2

-15V

47P 50V

D1
1N41 48

D2

1N4148

C7

G

+15v

TL072

-15V

R4

C6
270P 250 V

2U2 6 3V
R6

4K7

U1A

22K

FootSwitch

2

0R0

C9

R21

LN1

150K

10N 1 00V

SK3
SJACK

G

AA

R19
100K

CD4069UBE

VDD

147

1 2

U2A

G

Clean Channel

C12

3N3 5 0V

Treble

VR4

R9
10K

22KB6S

C14

220N 63 V

Bass

VR2

100K A6S

220N 63 V

Mid

C13

VR3

C10

100N 63 V

2K2B6S

G

100N 63V

C19

100K A6SD

LN2
0R0

G

VR5A

1N41 48

G

Drive Channel

R8
100K

Hard wire on top side of pcb

-15V

R16
10K

SW1A
2P2WPS

G

SW1B
2P2WPS

G

Channel Select

3

Q2
2N38 19

D7

TL072

R3
10K

G

Drive On

R13
1K

D4
3V9 Z D0. 5W

R18
100K

G

R5
33K

C17

10N 100V

U1B

-15V

G

R20

47K

C8

100N 63 V

D5
LED3MMG

R15
2K2

TS2
BC307

R24
1M

U2B

3 4

CD4069UBE

VR1
100K A6S

G

R14

G

100K

R12
470K

G

C5
1N 10 0V

C15
100N 63V

C20
100N 63 V

VR5 B
100K A6SD

-15V

G

4

R11
10K

TS1
BC307

U2C

5 6

R22
47K

CD4069UBE

C18
100N 63V

R10
100K

R25
1M

22N 100V

R7
220K

C11
100N 63 V

G

5

C21

47P 50V

R23
1M

U2D

C22

R26
220K

Q1
2N38 19

9 8

CD4069UBE

D3
1N41 48

LN7
0R0

R36
3K3

220N 63V

220N 63V

C28
C31

100N 63V

LN3
0R0

C32

3N3 5 0V

C23

Treble

G

VR9

22KB6S

Bass

VR7
100K A6S

VR8

2K2B6S

Mid

+15V

TL072

-15V

R33

10K
SW2B

R35
10K

G

6

R29
10K

U3A

2P2WPS

Max On/Off

R28
6K8

2P2WPS
SW2A

100N 63V C25

R34
10K

G G

R37
15K

C27

4N7 1 00 V

R30
15K

TL072

R32
10K

1N 10 0V

U3B

C26

100K A6S

VR6

Master Volume

R31
22K

C24
47N 100V

LN6
0R0

G

R27
220K

7

Tape/CD In

SK2

G

G

PHONOSTV

Q3

2N38 19

D8

1N41 48

LN5

Top

Bot

0R0

R43
22K

R46
22K

R48
10K

G

R38
220K

LN8
0R0

TL072

G

FXSEND

FXRETURN

DSP Level

8

R52
100K

D10
1N41 48

R40
100K

100K

LN12
0R0

D9
1N41 48

LN15
0R0

C30

47P 50V
R39

100K

U4B

TL072

LN9
0R0

G

R41

+15V -15V

C29

47P 50V

-15V

U4A

+15V

R50
1K

VR1 0
22KB6S

G

LN14

C C

TO OUTPUT PCB

9353/9391

Programming He ader

HD2

123456

PTA0
PTA1

PTA2/IRQ

PTA3
PTA4

D D

PTA5/OSC

FX Return
FX Send

123456

+5VDSP

-15V
G

HD1

1

DSP Program Select

SW3
16PGRY

1
2
3
4

C

FXRETURN

FXSEND

+15V

G

LN16
0R0

NOTE:

2

HD6WL

HD3

123456

R44

R45

R51
330R 5W

LN10
0R0

C38
10U 5 0V

G

15V Z D1. 3W

560R 5W

560R 5W

15V Z D1. 3W

+15VDSP

15V Z D1. 3W

G

D11

D14

G G

D12

G G

IN OUT

GND

G

U5
7805

LN11
0R0

C36
47U 5 0V

C37
47U 5 0V

G

C3

-15V

100N 63V

C1
100N 63 V

G

+5VDSP

C33

C34
100N 63 V

10U 5 0V

3

+15V

+15V

R17
1K

G

D6
5V1 Z D0. 5W

4

VDD

G

C16
470U 16 V

-15V

R49
4K7

D13
LED3MMR

Power

G

Line Out

G

SK4
MJACK

C35

R47
100K

R42
1K

6

G

2U2 6 3V

G

5

0R0

NOTE: MXD65 / R51 = 270R
NOTE: MXD120 / R51 = 330R

NOTE: All resistors to be 1/4W unless otherwise stated
NOTE: All capacitors to be rated at 16V or higher

Title

MXD65 / MXD120 PREAMP

Number Revis ionSize

A3

Date: 10/1 0/2 003 Sheet of
File: C:\D ocu ments and Sett in gs\..\9387_6 .Sch Drawn By:

9387 6

7

119387_6.Sch

Rich Thompson

8

1

A A

2

3

4

5

6

7

8

+40V-40V

HD1

123456

To Preamp PCB

HD6WL

B B

C C

G

HARDWIRED SOCKET

Wir e d D i rec t to O u tp ut PC B

FX Sen d

SK2
MJACKGSJ

FX Retur n

Gi

R3
1K

Q1
2N38 19

Gmu

C5
100U 25V

Gmu

Gmu

Gi

D4
1N41 48

TS8

MPSA42

C1

2U2 6 3V

D2
3V9 Z D0. 5W

D1
3V9 Z D0. 5W

R12
10K

Gmu

Gi

R13
33K

OFFSET ADJ

C2

R4
10K

1N 10 0V

Gi

C6
1U 63 V

Gmu

Gi

G

100R

LN10
0R0

+45V

R9
100R

R8

TS4
MPSA92

1K

TS2

MPSA92

R1

VR1

1KH

TS1
MPSA92

R7
220R

R2
100R

TS3
MPSA92

Gi

R6
100R

100P 100 V

C3
47U 5 0V

C4

-45V2

LN5
0R0

R5
100K

TS5
MPSA42

LN3
0R0

R10
2K2

R16
330R

R15
10K

-45V2

C7

47P 50V

LN4
0R0

LN8
0R0

R11
220R

TS6
MPSA92

D3
1N41 48

TS9

MPSA42

TS10

MPSA92
D7
1N41 48

2U2 6 3V

TS7
SAP16N

100N 63 VC10

R17
330R

1N41 48D6

R18

6K8

C11

6K8R19
330RR20

100N 63 VC13

G

G

1N41 48D8

TestPoint1

BIAS ADJ

TestPoint2

LN9
0R0

R22
220R

VR2
470RH

R14
0R22 5W

R21
0R22 5W

SAP16P
TS11

-45V

D5
1N40 07

D9
1N40 07

C16
47N 1 00V

R23
10R 2W5

G

R24
10R 2W5

L1
COIL20T

Extension Loudspeak er

Internal Loudspeak er

SP4
SPADE 4.8

SP6
SPADE 4.8

R29

R28

0R22 5W

220R

G

SK4
MJACKSJ

Head Version Only!

Mai n s T ra nsf orm er
230V = 5600-2050B
120V = 5600-2052B

MAINS FUSE 230V =T2A L, 115V = T5A L

Mains In

IEC Inlet

Green/Yellow

D D

Flame proof resister

FP

Must only be replaced with same type and rating

Indicates safety critical component
Must only be replaced with approved type

Black(Brown)

Fuse Integral to IEC

White (Blue)

Chassis Transformer Primary

1

Fuse

Mains Switch

AC Line(Live)

AC Input (Neutral)

NOTE:
Set VR5 to give 20mV across TP1 and TP2

Refer to service manual before adjusting bias preset

2

MAINS TRANSFORMER

These items not on pcb

3

SP3

SPADE4.8
SP1

SPADE4.8
SP2

SPADE4.8

G

4

1N40 07

C15

220N 250V

LN6
0R0

D11

D10

BR1

1N40 07

+V

AC
AC

-V

6A 20 0V

+45V

C9

C14
100N 63V

4700 U 63V

G

-45V

5

C12

4700 U 63V

-45V2

C8
100N 63V

Gmu

LN7
0R0

R26

10R 2W5

R25
10R 2W5

6

BLT

Industries

+40V

G

-40V

Title

MXD120 OUTPUT

Number Revis ionSize

A3

Date: 23/1 0/2 003 Sheet of
File: D:\93 91_3\93 91 _3. Sch Drawn By:

9391 3

7

119391_3.Sch

Rich Thompson

8