Philips MC-235-B Service Manual

Micro System

MC230/05/21M/22/25/30

MC235B/05/12/37/79,MC235/37/79

TABLE OF CONTENTS

Location of pc boards & Version variations................1-2

Technical Specifications .............................................1-3

Measurement setup....................................................1-4

Service Aids, Safety Instruction, et c...........................1-5

Disassembly Instructions & Service positions .............. 2

Service Test Programs ...............................................3-1

Set Block diagram ......................................................4-1

Set Wiring diagram .....................................................5-1

Power Board .................................................................. 6

Key Board ...................................................................... 7

Main Board .................................................................... 8

Displsy Board.................................................................9

Set Mechanical Exploded view & parts list .................10

Revison List ................................................................. 11

©

Copyright 2008 Philips Consumer Electronics B.V. Eindhoven, The Netherlands

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or
transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise without
the prior permission of Philips.

Published by SL 0829 Service Audio Printed in The Netherlands Subject to modification

Page

CLASS 1

LASER PRODUCT

GB

3141 785 30025

Version 1.5

LOCATION OF PRINTED CIRCUIT BOARDS

D

RA
OB B_YEK

1-2

HEADPHONE BOARD

DISPLAY BOARD

MAIN BOARD

KEY_A BOARD

FM/AM BOARD

KEY_C BOARD

SPEAKER BOARD

POWER BOARD

VERSION VARIATIONS:

SDR

MC230

x x
x x sweN

Type /Versions:

Features &
Board in used:

Line Out
Video Out
Surround Out
Subwoofer Out
Power Booster Out
Digital Out
Digital in
Matrix Surround

Dolby Pro Logic (DPL)
Incredible Surround
Karaoke Features
Vo xrotceleS egatl
ECO Power Standby (LCD Display Off) x x
ECO6 Tuner Board - Systems Non-Cenelec x x x
ECO6 Tuner Board - Systems Cenelec x x
USB PC LINK

/21 /22 /25 /30 /37

MC235

/79

/37

xx

x

MC235B

/79 /05 /12

x

x xx x ni RDC / ni xuA

x

x

x

x

x

xx
xx

xx

xx

SPECIFICATIONS

GENERAL:

Mains voltage : 120/240V ± 15% Switchable for /21

120V ± 10% for /37
230V ± 10% for /22/25

240V ± 10% for /30
Mains frequency:50/60Hz
Clock accuracy : < 4 seconds per day
Dimension centre unit : 250 x 245 x 96 (mm)

Power consumption
Active : 15W for /21/22/25/37/30
Standby : < 6W (DEMO mode off)
ECO Power Standby : < 1W for /22/25

TUNER:
FM

Tuning range : 87.5-108MHz
Grid : 50kHz

100kHz for /21/37
IF frequency : 10.7MHz ± 20kHz
Aerial input : 75 Ω coaxial

300 Ω for /37
Sensitivity at 26dB S/N : < 22dBf
Selectivity at 300kHz bandwidth : > 33dB
Image rejection : > 20dB [> 25dB]
Distortion at RF=1mV, dev. 75kHz : < 3%

-3dB Limiting point : < 23.5dB
Crosstalk at RF=1mV, dev. 40kHz : > 26dB

1-3

Input sensitivity

Aux in (at 1kHz) : 500mV at 600 Ω

Output sensitivity

Headphone output at 32 ohm : 15mW ± 2dB (Max. vol.)

COMPACT DISC:

Frequency response within ± 3dB : 63Hz - 14kHz
Output level (in Vrms) : 500mV, Z
Signal/Noise ratio (A-weighted) : > 67dBA
Distortion at 1kHz : < 0.02%
Channel unbalance at 1kHz : < ±2dB
Channel separation at 1kHz : > 30dB
Emphasis : 15/50 µS (switched

automatically by CD10)
THD Noise(1kHz) : < 1.5%
Outband Attenuation : > 35dB

[....] Values indicated are for /22/25 only.

= 100Ω

out

MW

Tuning range : 531-1602kHz

530-1700kHz for /21/37

Grid : 9kHz

10kHz for /21/37
IF frequency : 450kHz ± 1kHz
Aerial input : Frame aerial 18.1µH
Sensitivity at 26dB S/N : < 4.0mV/M
[> 3.25mV/M]
Selectivity at 300kHz bandwidth : > 20dB
IF rejection : > 24dB
Image rejection : > 20dB [> 28 dB]
Distortion at RF=50mV, M=80% : < 5%

AMPLIFIER:

Output power
L & R : 2 x 5W FTC (4Ω, 1kHz, 10% THD)
Frequency response within -3dB : 60Hz-14kHz
Digital Sound Control (DSC) : Jazz / Rock / Pop / Classic
Dynamic Bass Boost (DBB) : Jazz / Rock / Pop / Classic

MEASUREMENT SETUP

Tuner FM

1-4

Bandpass

LF Voltmeter

e.g. PM2534

RF Generator

e.g. PM5326

DUT

250Hz-15kHz

e.g. 7122 707 48001

Ri=50Ω

S/N and distortion meter

e.g. Sound Technology ST1700B

Use a bandpass filter to eliminate hum (50Hz, 100Hz) and disturbance from the pilottone (19kHz, 38kHz).

Tuner AM (MW,LW)

RF Generator

e.g. PM5326

Ri=50Ω

DUT

Frame aerial

e.g. 7122 707 89001

Bandpass

250Hz-15kHz

e.g. 7122 707 48001

LF Voltmeter

e.g. PM2534

S/N and distortion meter

e.g. Sound Technology ST1700B

To avoid atmospheric interference all AM-measurements have to be carried out in a Faraday´s cage.
Use a bandpass filter (or at least a high pass filter with 250Hz) to eliminate hum (50Hz, 100Hz).

CD

Use Audio Signal Disc
(replaces test disc 3)

DUT

L

R

SBC429 4822 397 30184

S/N and distortion meter

e.g. Sound Technology ST1700B

LEVEL METER

e.g. Sennheiser UPM550

with FF-filter

Recorder

Use Universal Test Cassette CrO2 SBC419 4822 397 30069

or Universal Test Cassette Fe SBC420 4822 397 30071

LF Generator

e.g. PM5110

DUT

L

R

S/N and distortion meter

e.g. Sound Technology ST1700B

LEVEL METER

e.g. Sennheiser UPM550

with FF-filter

SERVICE AIDS

1-5

Service Tools:

Universal Torx driver holder .................................. 4822 395 91019

Torx bit T10 150mm ............................................. 4822 395 50456

Torx driver set T6 - T20 ......................................... 4822 395 50145

Torx driver T10 extended ...................................... 4822 395 50423

Cassette:

SBC419 Test cassette CrO2 ................................. 4822 397 30069

SBC420 Test cassette Fe ..................................... 4822 397 30071

MTT150 Dolby level 200nWb/M ............................ 4822 397 30271

Compact Disc:

SBC426/426A Test disc 5 + 5A ............................ 4822 397 30096

SBC442 Audio Burn-in Test disc 1kHz ................. 4822 397 30155

SBC429 Audio Signals disc .................................. 4822 397 30184

Dolby Pro-logic Test Disc ...................................... 4822 395 10216

HANDLING CHIP COMPONENTS

ESD Equipment:

Anti-static table mat - large 1200x650x1.25mm ... 4822 466 10953

Anti-static table mat - small 600x650x1.25mm ..... 4822 466 10958

Anti-static wristband .............................................. 4822 395 10223

Connector box (1MΩ) ............................................ 4822 320 11307

Extension cable

(to connect wristband to conn. box) .................. 4822 320 11305

Connecting cable

(to connect table mat to conn. box) .................. 4822 320 11306

Earth cable (to connect product to mat or box) .... 4822 320 11308

Complete kit ESD3

(combining all above products) ......................... 4822 320 10671

Wristband tester .................................................... 4822 344 13999

1-6

GB

All ICs and many other semi-conductors are
susceptible to electrostatic discharges (ESD).
Careless handling during repair can reduce life
drastically.
When repairing, make sure that you are
connected with the same potential as the mass
of the set via a wrist wrap with resistance.
Keep components and tools also at this
potential.

Tous les IC et beaucoup d’autres
semi-conducteurs sont sensibles aux
décharges statiques (ESD).
Leur longévité pourrait être considérablement
écourtée par le fait qu’aucune précaution n’est
prise à leur manipulation.
Lors de réparations, s’assurer de bien être relié
au même potentiel que la masse de l’appareil et
enfiler le bracelet serti d’une résistance de
sécurité.
Veiller à ce que les composants ainsi que les
outils que l’on utilise soient également à ce
potentiel.

F

WARNING

ATTENTION

ESD

D

WARNUNG

Alle ICs und viele andere Halbleiter sind
empfindlich gegenüber elektrostatischen
Entladungen (ESD).
Unsorgfältige Behandlung im Reparaturfall kan
die Lebensdauer drastisch reduzieren.
Veranlassen Sie, dass Sie im Reparaturfall über
ein Pulsarmband mit Widerstand verbunden
sind mit dem gleichen Potential wie die Masse
des Gerätes.
Bauteile und Hilfsmittel auch auf dieses gleiche
Potential halten.

NL

Alle IC’s en vele andere halfgeleiders zijn
gevoelig voor electrostatische ontladingen
(ESD).
Onzorgvuldig behandelen tijdens reparatie kan
de levensduur drastisch doen verminderen.
Zorg ervoor dat u tijdens reparatie via een
polsband met weerstand verbonden bent met
hetzelfde potentiaal als de massa van het
apparaat.
Houd componenten en hulpmiddelen ook op
ditzelfde potentiaal.

Tutti IC e parecchi semi-conduttori sono
sensibili alle scariche statiche (ESD).
La loro longevità potrebbe essere fortemente
ridatta in caso di non osservazione della più
grande cauzione alla loro manipolazione.
Durante le riparazioni occorre quindi essere
collegato allo stesso potenziale che quello della
massa dell’apparecchio tramite un braccialetto
a resistenza.
Assicurarsi che i componenti e anche gli utensili
con quali si lavora siano anche a questo
potenziale.

WAARSCHUWING

I

AVVERTIMENTO

GB

Safety regulations require that the set be restored to its original
condition and that parts which are identical with those specified,
be used

Safety components are marked by the symbol

!

.

NL

Veiligheidsbepalingen vereisen, dat het apparaat bij reparatie in
zijn oorspronkelijke toestand wordt teruggebracht en dat onderdelen,
identiek aan de gespecificeerde, worden toegepast.

De Veiligheidsonderdelen zijn aangeduid met het symbool

!

F

Les normes de sécurité exigent que l’appareil soit remis à l’état
d’origine et que soient utiliséés les piéces de rechange identiques
à celles spécifiées.

Less composants de sécurité sont marqués

!

D

Bei jeder Reparatur sind die geltenden Sicherheitsvorschriften zu
beachten. Der Original zustand des Geräts darf nicht verändert werden;
für Reparaturen sind Original-Ersatzteile zu verwenden.

!

Sicherheitsbauteile sind durch das Symbol

markiert.

I

Le norme di sicurezza esigono che l’apparecchio venga rimesso
nelle condizioni originali e che siano utilizzati i pezzi di ricambio
identici a quelli specificati.

Componenty di sicurezza sono marcati con

!

CLASS 1

LASER PRODUCT

GB

Invisible laser radiation when open.
Avoid direct exposure to beam.

Osynlig laserstrålning när apparaten är öppnad och spärren
är urkopplad. Betrakta ej strålen.

SF

Avatussa laitteessa ja suojalukituksen ohitettaessa olet alttiina
näkymättömälle laserisäteilylle. Älä katso säteeseen!

DK

Usynlig laserstråling ved åbning når sikkerhedsafbrydere er
ude af funktion. Undgå udsaettelse for stråling.

S

Warning !

Varning !

Varoitus !

Advarse !

GB

After servicing and before returning set to customer perform a leakage
current measurement test from all exposed metal parts to earth ground to
assure no shock hazard exist. The leakage current must not exceed

0.5mA.

F

"Pour votre sécurité, ces documents doivent être utilisés par
des spécialistes agréés, seuls habilités à réparer votre
appareil en panne".

PREP ARATIONS AND CONTROLS

Preparations

Rear connections

The type plate is located at the rear of the

system.

A

Power

Before connecting the AC power cord to the

wall outlet, ensure that all other connections

have been made.

– If your system is equipped with a Voltage

Selector, set the VOLTAGE SELECTOR to the

local power line voltage.

WARNING!

–For optimal performance, use only the

original power cable.

–Never make or change any connections

with the power switched on.

To avoid overheating of the system, a safety

circuit has been built in. Therefore, your

system may switch to Standby mode

automatically under extreme conditions. If

this happens, let the system cool down

before reusing it (not available for all versions).

B

Antennas Connection

Connect the supplied MW loop antenna and FM

antenna to the respective terminals. Adjust the

position of the antenna for optimal reception.

MW Antenna

Position the antenna as far as possible from a TV,

VCR or other radiation source.

MW loop

antenna

FM wire antenna

AC power cord

Speakers

(right)

Speakers

(left)

NOT FOR ALL

VERSIONS

VOLTAGE

SELECTOR

110V-

127V

220V-

240V

FM Antenna

For better FM stereo reception, connect an

outdoor FM antenna to the FM AERIAL (FM

ANTENNA) terminal.

C

Speakers Connection

Front Speakers

Connect the speaker wires to the SPEAKERS

terminals, right speaker to "RIGHT" and left

speaker to "LEFT", colored (marked) wire to

"+" and black (unmarked) wire to "-".

Fully insert the stripped portion of the speaker

wire into the terminal as shown.

Notes:

–For optimal sound performance, use the

supplied speakers.

– Do not connect more than one speaker to any

one pair of

+

/

-

speaker terminals.

– Do not connect speakers with an impedance

lower than the speakers supplied. Please refer to

the SPECIFICATIONS section of this manual.

Optional connection

The optional equipment and connecting cords

are not supplied. Refer to the operating

instructions of the connected equipment for

details.

Connecting other equipment to your

system

Connect the audio left and right OUT terminals

of a TV, VCR, Laser Disc player, DVD player or

CD Recorder to the AUX-IN terminals.

Note:

– If you are connecting equipment with a mono

output (a single audio out terminal), connect it to

the AUX left terminal. Alternatively, you can use a

“single to double” cinch cable (the output sound

still remain mono).

Before using the remote control

1

Pull out the plastic protective sheet.

2

Select the source you wish to control by

pressing one of the source select keys on the

remote control (for example CD, TUNER).

3

Then select the desired function (for example

ÉÅ , í , ë).

plastic

protective

sheet

Replacing battery (lithium

CR2025) into the remote control

1

Pull out the knob

A

slightly to the left.

2

Pull out the battery compar tment

B

.

3

Replace a new battery and fully inser t the

battery compar tment back to the original

position.

CAUTION!

Batteries contain chemical substances, s o

they should be disposed off properly.

Preparations

1-7

PREP ARATIONS AND CONTROLS

)

1

3

4

6

7

8

9

5

!

0

2

1

!

7

0

8

*

%

@

3

#

$

&

^

(

5

Controls

Controls on the system and

remote control

1

STANDBY-ON/ ECO POWER

– switches the system on or to Eco Power standby.

2

Display

– shows the status of the system.

3

OPEN • CLOSEç

– opens/ closes the CD door.

4

IR

– remote sensor

5

VOLUME (3 / 4 ) (+/-)

– adjusts the volume level.

6

CD Door

7

Mode Selection

SEARCH/ TUNE (à / á)

for TUNER ........ tunes to a station

for CD ................. fast searches back and forward

within a track/ CD.

STOP 9............ stops CD playback or erase a

CD programme.

PLAYÉÅ ...... star ts or interrupts playback.

PRESET (¡ / ™)

for TUNER ........ selects a preset radio station.

for CD ................. skips to the beginning of a

current track/ previous/

subsequent track

8

DBB (Dynamic Bass Boost)

– enhances the bass.

9

BAND

– selects a waveband.

0

PROGRAM

for CD ................. programmes tracks and reviews

the programme.

for TUNER ........ programmes tuner stations.

!

SOURCE

– selects the respective sound source for CD/

TUNER/ AUX.

@

CLOCK SET

– sets the clock function.

–views the clock.

#

TIMER

– activates/ deactivates or sets the timer function

$

SLEEP

– activates/deactivates or selects the sleeper time.

%

DSC (Digital Sound Control)

– selects sound character istics: ROCK/ JAZZ/

POP/ CLASSIC.

Notes for remote control:

– First select the source you wish to control

by pressing one of the source select keys on

the remote control (for example CD,

TUNER).

– Then select the desired function (for

example ÉÅ, ¡

, ™).

^

RDS.NEWS

– activates RDS news and Traffic Announcement.

–for tuner, displays RDS information.

&

MUTE

–interrupts and resumes sound reproduction.

*

REPEAT

– repeats a track/ CD programme/ entire CD.

(

SHUFFLE

–plays CD tracks in random order.

)

– connects headphones

1-8

PREP ARATIONS AND CONTROLS

Important notes for users in the

U.K.

Mains plug

This apparatus is fitted with an approved 13

Amp plug. To change a fuse in this type of plug

proceed as follows:

1

Remove fuse cover and fuse.

2

Fix new fuse which should be a BS1362 5 Amp,

A.S.T.A. or BSI approved type.

3

Refit the fuse cover.

If the fitted plug is not suitable for your socket

outlets, it should be cut off and an appropriate

plug fitted in its place.

If the mains plug contains a fuse, this should

have a value of 5 Amp. If a plug without a fuse

is used, the fuse at the distribution board

should not be greater than 5 Amp.

Note: The severed plug must be disposed of to

avoid a possible shock hazard should it be

inserted into a 13 Amp socket elsewhere.

How to connect a plug

The wires in the mains lead are coloured with

the following code: blue = neutral (N),

brown = live (L).

¶ As these colours may not correspond with the

colour markings identifying the terminals in

your plug, proceed as follows:

–Connect the blue wire to the terminal

marked N or coloured black.

–Connect the brown wire to the terminal

marked L or coloured red.

–Do not connect either wire to the earth

terminal in the plug, marked E (or e) or

coloured green (or green and yellow).

Before replacing the plug cover, make cer tain

that the cord grip is clamped over the sheath

of the lead - not simply over the two wires.

Copyright in the U.K.

Recording and playback of material may

require consent. See Copyright Act 1956 and

The Performer’s Protection Acts 1958 to 1972.

Norge

Typeskilt finnes på apparatens underside.

Observer: Nettbryteren er sekundert

innkoplet. Den innebygde netdelen er

derfor ikke frakoplet nettet så lenge

apparatet er tilsluttet nettkontakten.

For å redusere faren for brann eller elektrisk

støt, skal apparatet ikke utsettes for regn eller

fuktighet.

Italia

DICHIARAZIONE DI CONFORMITA ’

Si dichiara che l’apparecchio MC230, MC235

Philips risponde alle prescrizioni dell’ar t. 2

comma 1 del D.M. 28 Agosto 1995 n. 548.

Fatto a Eindhoven

Philips Consumer Electronics

Philips, Glaslaan 2

5616 JB Eindhoven, The Netherlands

CAUTION

Use of controls or adjustments or

performance of procedures other than

herein may result in hazardous

radiation exposure or other unsafe

operation.

VAROITUS

Muiden kuin tässä esitettyjen

toimintojen säädön tai asetusten

muutto saattaa altistaa vaaralliselle

säteilylle tai muille vaarallisille

toiminnoille.

1-9

PREP ARATIONS AND CONTROLS

WARNING

Under no circumstances should you try to repair the system yourself, as this will invalidate the

warranty. Do not open the system as there is a risk of electric shock.

If a fault occurs, first check the points listed below before taking the system for repair. If you

are unable to remedy a problem by following these hints, consult your dealer or Philips for help.

Problem Solution

CD OPERATION

“NO DISC” is displayed. –Insert a disc.

– Check if the disc is inserted upside down.

–Wait until the moisture condensation at the lens

has cleared.

–Replace or clean the disc, see “Maintenance”.

–Use a finalised CD-RW or CD-R.

RADIO RECEPTION

Radio reception is poor. – If the signal is too weak, adjust the antenna or

connect an external antenna for better reception.

– Increase the distance between the Micro HiFi

System and your TV or VCR.

GENERAL

The system does not react when buttons –Remove and reconnect the AC power plug and

are pressed. switch on the system again.

Sound cannot be heard or is of poor – Adjust the volume.

quality

.

–Disconnect the headphones.

– Check that the speakers are connected correctly.

–Check if the stripped speaker wire is clamped.

The left and right sound outputs are – Check the speaker connections and location.

reversed.

The remote control does not function – Select the source (CD or TUNER, for example)

properly. before pressing the function button (ÉÅ,í,

ë).

–Reduce the distance between the remote control

and the system.

– Insert the battery with its polarities

(+/– signs) aligned as indicated.

–Replace the batter y.

–Point the remote control directly toward

IR sensor on the front of the system.

The timer is not working. – Set the clock correctly.

–Press TIMER to switch on the timer.

The Clock/Timer setting is erased. –Power has been interrupted or the power cord

has been disconnected. Reset the clock/timer.

Troubleshooting

1-10

2-1

2-1

DISMANTLING INSTRUCTIONS

Dismantling of the Rear Portion

1) Remove 11 screws A and B as indicated to remove the

Rear Cabinet.

2) Remove 2 screws C as indicated to loosen the Speaker

Wire Holder.

3) Remove 2 screws D as indicated to loosen the Speaker

Board .

4) Remove 2 screws E as indicated to loosen the AUX IN

jack.

Dismantling of the Front Boards and CD Door

1) Loosen 3 screws G each to remove the CD Mechanism
Holder Bracket.

2) Loosen 7 screws F1 and F2 as indicated to remove the
Main Board.

3) Remove 3 screws H as indicated to loosen the Gear Motor
Module.

4) Loosen 4 screws I (see Figure 3) to remove the Key_C
Board.

5) Loosen 2 screws J (see Figure 3) to remove the Display
Board.

DISMANTLING INSTRUCTIONS

Repair Hints & Service Positions

Note: The flex cables are very fragile, care should be taken

not to damage them during repair. After repair, be
very sure that the flex cables are inserted properly
into the flex sockets before encasing, otherwise faults
may occurs.

Service position A

Service position B

Figure 1

Figure 3

6) Loosen 4 screws K (see Figure 3) to remove the Key_B
Board.

7) Loosen 8 screws L (see Figure 3) to remove the Key_A
Board.

8) Loosen 8 screws M (see Figure 3) to remove the Door Eject
Lever Bracket Right/Left, then remove CD door.

Figure 4

Figure 5

Service position C

Figure 2

Figure 6