Bang and Olufsen Beosound Century Service manual

Bang&Olufsen

rt.

BeoSound

Typ€ 2651, 2652, 2654, 265/l

Century

Circuit Description

3540178 Danish 3540179 3540180 German 3540181 Fi€nch

English

SERVICE MANUAL

CONTENTS

Survey of modules Specification Wiring Brief

operation

Guidelines for service

of transformer.......,.........

guide

use...............

Bang

1-1

1-2

..

1-3 1-5

&Olufsen

Diagrams

List of List of mechanical Adjustments

etc.

Explanation Wiring Block Diagrams

electrical

Adjusffnents

Tuner..........

Tape............

...............

cD

Loudspeaker Replacement Replacement Replacement

Repair Lubrication Replacement Tape Wow frequencies Test Test mode... Display of tuner variant Gearbox

Keyboard test ..............

LED test Display Presetting Continuous operation Speaker

parts

and repair

of PCB 2 Amplifier of of a

.............

tips

of CD drive mechanism

functions ...................

test ...........,..

of software version

of EEPROM

sound

diagram

diagrams ..................

..........

tips

..................

PCB

3 or 31C4

speaker unit..............

of tape recorder

level

adjustment

of diagram

[ffi;;;; ;;;;;il;il::::::::

GB 5-1 5-1 5-1 5-3 5-4 5-4 5-5 5-5

5-6

5-5

5-6 5-5 5-7 5-7 5-7 5-7 5-7

5-7 5-8 5-8 5-8 5-8

::::::: ::::::::::::::::::::::: :::::r ::::::::::::::::

5-9

DF 5-10 5-10 5-10 5-13 5-25 5-14 5-25 5-14 5-25 5-15 5-27 5-15 5-27

5-17 5-29 5-17 5-29 5-17 5-29 5-17 5-29 5-17 5-29 5-18 5-30 5-18 5-30 5-18 5-30

s-18

5-18

5-18 5-30 5-19 5-31 5-19 5-19 5-31 5-19 5-31

5-20

2-3

2-9

2 2-1 2-2

-2-8

-2-24

5-22

5-22 5-22

5-30 5-30

s-31

5-32

Disassembly

Glass

door... ...................;.

Front

fabric t,"r"..........:::::::::::::::::::::::::::::::::::::::::::::::.::::::.:::.::::::::::::::...........

Handle/PCB 21 Active antenna

panel

Rear CD front frame/PCB 20 Tape/Keyboard Gear box/PCB 9 Gear sensor

iding bracket

Sf Transformer PCB 1 - PCB Tape

mechanism ..............

Insulation

test

front frame..........

for

22

Door sensor

glass

door............

5-1 6-l

5-1 6-2

5-3

.. 5-4

54

6-4

64

......... 6-5 - 6-7

5-8

-

s

I

Bang

&Olufsen

1-1

SURVEY OF MODULES

I

FM/AM

Amplifier

Output Amplifier, left ..............

Output Amplifier, right

2 Door

2 Amplifier

decoder

processing

Sound

sensor transmit....

power

supply diagr. M

..... diagr. A

page

.......

page

............ .

page

2-10

diagr. I

2-19

.. diagr.

2-20

diagr.

2-21

diagr. L

2-22

2-23

3 Microcomputer...........

4 oisptay & Keyboard

J

K

Power

5

Supply & Motor

6 rR Receiver...................

7 rape

7 tape

7

dieital

analos

Reset converter

;$:rr1;;

;"rJ:rrl;l

Control diagr, M

page

2-23

;.T:rr1;l

;#:rr:;?

;#?:;;

;$:T-r?

I

.f

I

Seen from

the

front

r

1-1

SURVEY OF

1-1

MODULES

servo

8 cD

CD Decoder

8

9 Gear-sensor

.................... ............. diagr.

................... diagr.

1o Mains

11 Re_deck electronic

12 Oscillator

17 FM

................... diagr.

Front

end

E

diagr.

page

2-15

page

F

2-16

G

2-17

;:i'1tl-ii

;$:T1?

.

diagr.

D

2-14

A

2-10

page

2O ooor Sensor receive.........

21 active FM Antenna

22 Crossover

network, left ...,,.,,.,,.,,

network, right ......,..... diagr.

..,...,,., diagr, L

page

2-22

diagr.

page

2-19

diagr. J

page

2-20

page

2-21

I

K

from the back

Seen

8

1/17

Z

1-2

SPECIFICATION

GUIDELINES

1-2

SPECIFICATION BeoSound rV ranfe FM-MW-LW Operation Optional Cabinet finish Front

cover

Acoustic

Active

speakers

Output

amplifier Sound Pressure Level Frequency Cabinet Croosover Active Woofer Tweeter Net

Tuner: PretuneJ radio FM section: FM range

FM aerial impedance Sensitivity Qulgting Signal-to-noise ratio

Totai Harmonic

Freqency Channel lmage rejection lF rejection

AM AM

Antenna Sensitivity

Signal-to-noise ratio Total Harmonic Selectivity 59

lmage

lF rejection

principle

crossover network

volume

separation

section: range

rejection

GUIDELINES FOR

Century

range

extra

system:

response

frequency

programs

sensitivity

Distortion

response

Distortion

SERVICE USE

Type 2651

Type

Direct, Beolink Black Grey-Red-Blue-Green,

2x2outputamplifier Class G 95 dB IEC noise/3m/stereo/room 75 - 20,000 Bass Reflex 3500 Hz 24 dB/octave Linkwitz/Ri

10cm-4"

1.8

1 .'l litres

30 FM

87.5

76.0 - 90.0 MHz 75 O <

1,4;rV 26 dB < 45prV >

66 dB mono

>

63 dB

<

0,8%o mono

< 1,0%o

40 - I > 33 dB lkHz > 75 dB >

80 dB

LW MW MW s20 tttOiiz Loop <

4mV/m 26dB

<

1.8mv/m 26

>

47dB 50mV/r < 3% 50mV/m noise >

42 dB 1494kHz >

40 dB 270kHz >

30 dB >

65 dB 270kHz >

50 dB 558kHz

EU

2652

cm

or AM

't08.0

-

5,000 Hz

150

522 - 1610 kHz GB

18.1prH

2653

cB,

easy-touch

1000, one-way

3/q"

-

50 dB S/N stereo

stereo

-279kHzGB

1494KHz

pushbuttons

-8

Hz +4

MHz

EU/GB

JAP

S/N mono

+1.5

S/N 156kHz

dB S/N 558kHz

gOitHt

USA/CAN, 2654

type

6037

dB

ley

dB

USA/CAN

96ikHz

JAp

Tape recorder: Compact

casette

c46

-

C120

-2

INES

1-2

SPECIFICATION

fape

transport

Tape

recording

Record

level

Noise

reduction

rape

swttcn

fape

fread

Wow

and flutter Speed deviation Fast

forward Frequency sig;at

Distortion Channel

Channel Erasure Erasure freqency

range

to-noise ratio

separation unbalance

GUIDELINES

system

Auto reverse HX PRO Auto

Record

Level NR Auto

ferro/chrome oynattoy <

<

< 120 50 - 14,000 > t > 56

> < >35dB1kHz <2dB >70dB 80 kHz

iHarO

0.15% DtN

+2o/o

sec.

C60

Hz

53 dB ferro

62 ;B ferro

dB chrome

64 dB chrome

3oh D31315

with noise

Hz

permalloy)

+3

dB chrome

with

noise reduction

reduction

Bang

&Olufsen

player:

CD

Drsc

type: Converter Frequency Signal-to-noise Harmonic

Connections: nuOio

Power

fotaiOimensionrW"|{*O

Weight

system

range

ratio

distortion

Aux

supply

consumption

(5")

12 cm B itstrea

m

-

20

20,000 kHz

>

94 dB

A-weighted

< O.025o/o

Pin t Pin Pin 3 AF Pin 4 N.C. Pin Pin Pin 7 N.C.

230V AC 240V 12OV AC toovnc Max. t wati in 75x37 75 12 kg

at

l.t.C.

2

Signal

in left

5 AF in right 6 N.C.

2651 EU

AC 2652

2653 USA/CAN

2654

50 watts

stand-by

x17

x 33.5 x 11

and

8 cm

+0.5

0 dB/1 kHz

ground

0.25-2V RM5

O.25-2V

GB

JAP

cm

cm on

(3")

dB/ 2 dB

47kO

RMS

47kO

wall bracket

Optional Beolink'1000 Carrying handle/active nfV

Wall bracket

Subj-ct

loop

antenna

to

accessories:

change

without

FM

antenna

notice

Type

1501, 1502

Type

2036

8720043

Type

2OaS

ltaly

--

Bang

WIRING OF TRANSFORMER

Type 2551

EU 230V-

&0lufsen

wtRtNG

r*o*rrJ*tf,

or

ffifr

ffiX

ffiil

ffiX

ffiil

PCB 10, Mains

ffiil

Qve,rN

.1

\

1-3

WIRING OF

Type 2552 GB 24OV-

1-3

TRANSFORMER

ffim

ffiil ffiil

ffiX

reil

PCB

10, Mains

Jl

II

1

1-4

Type

2553

cDN,

USA 120V-

WIRING

OF TRANSFORMER

1-4

PCB 10,

Mains

ffiil

l

QvnrNS

-/_.-

"'I

g

,\

3\

Bang

BRIEF BeoSound relevant guide).

RADIO: Turn on

Change display indication (display

Tune into

radio

&Olufsen

OPERATION GUIDE

Century is

buttons light

radio

the

=

frequency)

and store all FM

stations in

primarily

up. Use Beolink'l 000for remote

the area

designed for

closeup operation.

control

1-''il'l'0

.,{,

$ltu

'

\'//'

\

N

\F

Z"nffiflNe 2 sec.

Only the (see

User's

DrspLAy:

p

EE.E

BRIEF

OPERATION

COMPACT DISC: Raise

the CD-clamp

Lower

the CD-clamp

playing

Start (Display

Browse

Select track number

the CD

=

track no.)

through tracks

1-5

GUIDE

(ex.

5)

1-!

BRIEF

Searches frequencies table signal

Key (ex.

Store the program

Store the station gram

Erase gram

Switching (not

Browse numbers

Key in

Select

up/down

for an

in frequency

87.5MHz)

station on a vacant

number

the station from no.

all types)

exact

another source

(0-30)

between FM/AM

through

program

the

accep-

(0-30)

pro-

to a

pro-

program

number

EE.E

1.5

E

P]D

P

E

P

E E.E

1

]D

Pause

the CD

Resume or change (display =

Change display indication (display

Random (display

blinking) Random (display when random

Select

another source

Switch to stand-by

AUXITLARY Open auxilay input

(start

now auxilary source)

player

playing

=

play

indication

play

indication rotates

after stop,

display indication

track time)

remaining

SOURCE:

status

on/off

play

is

time)

on)

Switch

to stand-by

ACTIVE OPTION:

Select active antenna

Cut out

REMOTE (No

Disable

Regain

ANTENNA

active antenna option

CONTROL:

light in buttons)

the remote

the remote control function

control

option

function

D

Switch

to stand-by

SOUND ADJUSTMENTS: Raises/lovers

Volume level

Store all sound levels

Loudspeaker

Bass level

Treble level

Loudness

levels

the

balance

t-5

GUIDE

1-5

BRIEF OPERATION GUIDE

DISPLAY: TAPE RECORDER:

playing

tl

t.\ 1

IE

lE

tl

ll

Start

Play the

Play from

I

f

I

Browse through tracks

Pause Fast forwards/rewinds

the tape

Erase tape

Resume

Noise reduction

Noise reduction on/off

(display when noise reduction is

the tape

other side

the beginning

the tape

recorder

(no

source)

playing

indication blinks

after stop

status

(turn)

off)

@r,"..

DISPLAY:

Dnn

-

nnn

NDD

nPl

DEE

DJl

I

nr-

NT

.,9

c

NU

a

1n

1D EE

Select another source

Recording (display

Auto reverse status

Auto reverse onlofl

(display when Start

on CD

as source)

Stop recording

Start recording

Pause the recording

Stop recording completely

pause

mode

blinks alternately)

indication blinks

reverse is

auto

recording

(only

track

if

CD

pause

is

off)

(ex.)

4

selected

mode

rEt

--l

\

rPr

D D

Lnud

Return to approx. recor-

ding start

Resume recording

pause

Select another source

Switch

stand-by

to

after

rPr

Bang

&Olufsen

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RAq<

TRFBI F TDtrRI tr

opEt,rcrosto

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CD ON,/OFF

rurrR

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IAPE ON,/OFF

F M,/AM

TEC TOR

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REG I S TER

3IC3

SYSTEM CONTROL

SH]FT

2rc 8

|

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I'C

SCL

STROBE

CLOCK

DATA

CE

COI,JNT ER

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STOP SIG.

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l'41CROCOI'.1PUTER

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KEYBOARD DATA

KEYBOARD STROBE

LED CLOCK

LED DATA

L =Oc. Ui

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SYS. ON/OFF TAPE oSC. &5/8.41

MOTOR ON/OFF

CLOSE

DOOR

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5TR2 I 8

DISPLAY

KEYBOARD

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