Philips MCM279/55 Schematic

MCM279

Service AIDS & CD playability ...........................1-1...1-4

Specifications ................................................................2

Connection & Controls ...................................................3

Disassembly Instructions ...............................................4

Block & Wiring diagrams ................................................5

MAIN BOARD ................................................................6

KEY & USB JACK BOARD ............................................7

POWER & AMP BOARD ................................................8

EXPLODE DIAGRAM .....................................................9

SERVICE PARTLIST ....................................................10

FACTORY PARTLIST ...................................................11

3141 785 32151

SERVICE AIDS

1-1

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

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.

WARNING

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

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

ESD

CLASS 1

LASER PRODUCT

Lead free

1-2

CD PLAYABILITY

Customer complaint

"CD related problem"

check playability

for at least 10 minutes

CHECK

playability

ok ?

Play a CD

Set remains closed!

"fast" lens cleaning

check playability

playability

ok ?

For flap loaders (= access to CD drive possible) cleaning method

is recommended

Standard repair procedure

clean the lens

check playability

playability

ok ?

add Info for customer

"SET OK"

return set

- 7

For description - see following pages

return set

replace CD Drive

return set

replace CD Drive

return set

playability

ok ?

check "EYE-Pattern"

EYE-Pattern

ok ?

check Laser current

Laser current

ok ?

check CD Drive offsets

replace Signal Processor

return set

CD Drive offsets

ok ?

replace CD Drive

return set

1-3

CD PLAYABILITY

CHECK

PLAYABILITY CHECK

For sets which are compatible with

use CD-RW Printed Audio Disc....................7104 099 96611

TR 3 (Fingerprint) TR 8 (600µ Black dot) maximum at 01:00

• playback of these two tracks without audible disturbance playing time for: Fingerprint ≥

Black dot from 00:50 to 01:10

• jump forward/backward (search) within a reasonable time

For all other sets

use CD-DA SBC 444A..................................4822 397 30245

TR 14 (600µ Black dot) maximum at 01:15 TR 19 (Fingerprint) TR 10 (1000µ wedge)

• playback of all these tracks without audible disturbance playing time for: 1000µ wedge ≥10seconds

Fingerprint ≥10seconds Black dot from 01:05 to 01:25

• jump forward/backward (search) within a reasonable time

CD-RW discs

10seconds

LIQUID LENS CLEANING

Before touching the lens it is advised to clean the surface of the lens by blowing clean air over it. This to avoid that little particles make scratches on the lens.

Because the material of the lens is synthetic and coated with a special anti-reflectivity layer, cleaning must be done with a non-aggressive cleaning fluid. It is advised to use “Cleaning Solvent B4-No2”, available with codenumber 4822 389 10026.

The actuator is a very precise mechanical component and may not be damaged in order to guarantee its full function. Clean the lens gently (don’t press too hard) with a soft and clean cotton bud moistened with the special lens cleaner.

The direction of cleaning must be in the way as indicated in the picture below.

CUSTOMER INFORMATION

It is proposed to add an addendum sheet to the set which informs the customer that the set has been checked carefully - but no fault was found. The problem was obviously caused by a scratched, dirty or copy-protected CD. In case problems remain, the customer is requested to contact the workshop directly. The lens cleaning (method 3) should be mentioned in the addendum sheet.

The final wording in national language as well as the printing is under responsibility of the Regional Service Organizations.

FAST LENS CLEANING (dry brush)

Use lens cleaning CD

SBC AC300...........................................9082 100 00043

Insert the lens cleaning CD, press PLAY and follow the voice guide´s instructions on the CD.

Sanyo DA12T3

CD Drive

VCC

VREF

1800

+5V_HF

VrefCD10

B C

GND

Laser power control

100n

2878

470n

2876

3821

3823

2880

33p

+5V

BC807-40

7879

3817

47R

3820

4R7

47R

3819

2879

2877

47u

7811-A

LM358D

10K

3822

47R

3818

2841

100n

47n

2869

+5V_HF

LASER DIODE

U >250mV

->Laser damaged !

4,6V

3,3V

3,9V

0,17V

Sanyo DA12T3

HF-Amplifier

680R

3905

3903 3K3

BC847B

7877

47n

2818

1K5

3902

470R

3893

+3.3V

2K2

3908

10K

3923

BC847B

7878

BC847B

7876

4n7

2813

3896 100R

220u

2885

2881 560p

47n

2887

560R

3901

2883 470n

2817

4u7

3n3

2814

3898 220R

3895

27K

470n

2884

+3.3V

3909

820R

3907

100R

3920

33K

3897

2882

82p

3K3

3904

2K7

3899

3906

470R

+5V_HF

HFIN

VrefCD10

100p

28152816

22n

LDON

to 3826,3827

VREF GE

VDDA1

VRIN

VSSA1

ISLICE

HFIN

HFREF

IREF

CD_DA: 0V / CD_RW: 3V

(A-D)

800mVpp

TB = 0.5µs/div

EYE-PATTERN

1,8V

1,2V

2,4V

2,6V

0,65V

CD PLAYABILITY CHECK

1-4

EYE-PATTERN SIGNAL – JITTER MEASUREMENT

Measure the signal on the input of the Signal processor using an analog oscilloscope. Please find the exact measuring point in your Service Manual.

See below examples of the signal. Amplitude should read at least 700mVpp using SBC444A.

CD DRIVE – LASER CURRENT MEASUREMENT

The laser current can be measured as a voltage drop on a resistor. The resistor is marked in every Service Manual. The value depends on the type of CD drive.

typical value most probably defect

VAMxxxx : 150-230mV MCDxx : 170-230mV DA1x : 210-250mV ≥350mV DA2x : 175-200mV Use SBC444A (CD-DA) for measurement.

≥

350mV

≥

300mV 250mV

≥

If the oscilloscope shows a signal like the ‘bad’ one, and/or the amplitude decreases within 1 minute - the CD drive has to be replaced.

good

bad

CD DRIVE – OFFSET MEASUREMENT

The photodiodes of the CD-drive may have an offset. These offsets have to be compensated by the signal processor. High offsets can lead to poor playability of some CDs (skipping tracks).

To measure the offset values, start the Program - section “Focus Test” without a CD.

The offsets can be measured with a DC Millivoltmeter directly on the connector (see drawing below). Pin numbering varies from drive to drive.

The values from diode A-D should read 0±10mV. Diodes E and F are less critical.

If one of the offsets is higher than ±10mV the CD drive has to be replaced. Otherwise replace the Signal Processor.

Service Test

2 - 1

AMPLIFIER

Output power ................................................30 W RMS

Signal-to-noise ratio ....................................... ≥ 65 dBA

Frequency response ............. 100 – 18kHz, ± 3 dB

Input sensitivity AUX ....................... 0.5 V (max. 1 V)

Impedance loudspeakers .....................................≥ 6 Ω

Impedance headphones .................... 32

Ω

-1000

..................................................................................... <15mW

CD PLAYER

Frequency range ....................................... 100 – 18kHz

Signal-to-noise ratio ............................................ 65 dBA

TUNER

FM wave range ...................................87.5 – 108 MHz

MW wave range ................................ 531 – 1602 kHz

Number of presets ........................................................ 40

Antenna

FM .................................................................... 75 Ω wire

MW ......................................................... Loop antenna

USB PLAYER

USB ......................................................................... V2.0/ V1.1

......................................... support MP3 and WMA files

Number of albums/ folders ................ maximum 99

Number of tracks/titles ...................... maximum 999

Ω

SPEAKERS

Bass reflex system Dimensions (w x h x d) .. 158 x 250x 185 (mm)

GENERAL INFORMATION

AC Power .......................... 110 – 240 V, 50 Hz/60Hz

Dimensions (w x h x d, with/without the stand)

............... 211 x 250 x 160/211 x 250 x 126 (mm)

Weight(with/without speakers) ......... 3.7 / 1.33 kg

Standby power consumption ............................ <2 W

Eco power standby ............................................... <1 W

Specifications and external appearance are subject to change without notice.

Connection

CONNECTION AND CONTROLS

3 - 1

Connection

Connecting a USB device or memory

Connecting an additional

appliance

FM antenna

VCR or other radiation source.

● Position the antenna as far as possible from a TV,

on the front

on the front panel of the main set.

card

By connecting a USB mass storage device

(including USB flash memory, USB flash players

or memory cards) to the Hi-Fi system, you can

enjoy the music stored on the external device

through the powerful speakers of Hi-Fi system.

Or,

panel of the main set.

for the devices with USB cable:

a. Insert one plug of the USB cable (not

supplied) to the socket

1 Insert the USB device’s USB plug into the socket

The wire antenna supplied can only be used to

receive nearby stations. For better reception we

recommend using a cable antenna system or an

outdoor antenna.

Extend the wire antenna and fit it to FM

ANTENNA as shown below

Insert the other plug of the USB cable to the b.

USB output terminal of the USB device.

on the front panel of the main set.

the card reader to the socket .

optimal reception (as far away as possible from

the TV, VCR or other radiation sources)

Fix the antenna’s end to the wall.

Connecting a non-USB device

It is possible to use an additional appliance, e.g.

TV, VCR or CD recorder with the set. On

Helpful hints:

Or,

for the memory card:

a. Insert the memory card into a card reader

(not supplied).

b. Use a USB cable (not supplied) to connect

Note: If you are using a cable antenna system or

an outdoor antenna, fit the antenna plug, instead of

the wire antenna, to FM ANTENNA .

Move the antenna in different positions for

MCM279, you can playback music from an

external source.1Insert one plug of the audio cable (not supplied)

to the socket AUX IN at the rear panel of the

–To receive optimal radio reception, put the main

unit and the antennas as far away as possible from

the power adaptor.

main set.

Connect the other end of the audio cable to the

AUDIO OUT terminal of the additional

appliance.

Always refer to the owner’s manual of other

equipment for complete connection.

Helpful hints:

–

3 Select AUX mode on the set.

Antenna connections

MW antenna

Connect the supplied MW loop antenna to the

“AM aerial” terminal. Adjust the position of the

antenna for optimal reception.

Warning:

– Never make or change connections with

Rear connections

the mains supply switched on.

– Install your set near the AC outlet and

where the AC power plug can be reached

easily.

Use the supplied speakers only. Using other

speakers can damage the set or the sound

quality will be negatively affected.

A Speaker connections

(red and black) and the cable of the right

● Connect the cable of the left speaker to LEFT

(red and black) as follows:

RIGHT

speaker to

a. Press the clip of the red terminal and fully

insert the stripped portion of the colored (or

marked) speaker cable into the socket, then

release the clip

Press the clip of the black terminal and fully b.

insert the stripped portion of the black (or

unmarked) speaker cable into the socket, then

release the clip

CONNECTION AND CONTROLS

set on and selects sound source CD, USB,

SOURCE

9 OPEN/CLOSE 0

0 DBB (Dynamic Bass Boost)

– turns the bass enhancement on/off

– opens/closes the CD door.

AUX

– selects sound source CD, USB, TUNER, or

TUNER or AUX

– In standby or Eco Power mode: switches the

STOP

– CD/USB: stops playback; erase a program

3 - 2

switches between

Controls on the set (illustrations

Controls

on page 3)

– jack for the external USB mass storage device

2 PROGRAM

programs tracks

programs preset radio stations

– CD/USB:

– Tuner:

VOLUME

– adjusts the volume level

– Clock/Timer: adjusts the hours and minutes

DISPLAY/CLOCK

- displays the set time

– Clock:

enters the clock setting mode

(press and hold for more than 2 seconds)

clock

display and playback display

during playback

- In standby mode:

– TUNER/Audio CD/AUX:

– MP3/WMA files: displays disc information

MICRO SYSTEM MCM279

ALBUM/ PRESET + /-

4 / ¢

backwards/forwards

– CD/USB: selects albums (for MP3/WMA only)

– TUNER: selects a preset radio station

– CD/USB: skips or searches CD tracks/titles

4mm

– Tuner: tunes to radio stationsÉÅ– CD/USB: starts or pauses playback

VOLUMEPROGRAM

ALBUM/PRESET

Always point the remote control

towards this sensor.

6 IR

– sensor for the infrared remote control

Helpful hints:

7 DSC (Digital Sound Control)

DISPLAY/CLOCK

JAZZ, POP, CLASSIC, OFF

– selects predefined sound settings: ROCK,

– press briefly to switch the set on or off (standby/

8 STANDBY-ON/ ECO POWER

ECO POWER);

– In standby or Eco Power mode: press and

lights up red when the set is

hold to toggle between Standby and ECO

POWER mode (power-saving mode)

Red indicator:

switched to ECO POWER mode

–

Controls

MPATIBLE

RW CO

R/CD

CD/CD

MP3

WMA

ECO POWER

SOURCE STOP

DSC

DBB

ANDBY

OPEN/CLOSE

CONNECTION AND CONTROLS

Mounting the stand onto the set

MCM279 is supplied with a stand, you may

attach or detach the stand to/from the main set.

Placing MCM279

Locate the bottom of the main unit and find the

slot, then slide the stand in the slot until it stops,

as indicated in the figure below.

3 - 3

Controls

copies one file or all files of a disc to an

USB:

external portable USB storage device/MP3

–

– set the sleep timer

3 SLEEP

4 MUTE

player.

& 0

– switches the sound off temporarily

during playback

switches the timer on/off

USB REC

– MP3/WMA files: displays disc information

$ DISPLAY

AUX

– selects the audio input from an additional

–

% TIMER ON/OFF

switches the set

connected appliance

on and selects the audio input from an

additional connected appliance

– In standby/Eco-power mode:

123

Remote control

– opens/closes the CD door.

à / á

– CD/USB: skips or searches CD tracks

7890!

í/

– CD/USB: selects previous/next track

backwards/forwards

– Tuner: tunes to radio stations

(

Numeric keypad (0-9)

– CD/USB: stops playback; erase a program

( 9

)

selects the next/previous album (for

3 / 4

CD/USB:

MP3/WMA only)

–

– Tuner: selects a preset station

)

¡%™

– selects track or station number

ÉÅ

DSC (Digital Sound Control)

JAZZ, POP, CLASSIC, OFF™DBB (Dynamic Bass Boost)

– selects predefined sound settings: ROCK,

– CD/USB: star ts or pauses playback.

– turns the bass enhancement on/off

USB DEL

USB device.

adjusts the volume level

– deletes one file or all files stored on the external

Notes for remote control:

– First select the source you wish to

–

7 VOL +/-

CD, TUNER).

control by pressing one of the source select

keys on the remote control (for example

System)

Data

adjusts the hours and minutes

REPEAT–selects continuous playback9SHUFFLE

– Clock/Timer:

selects random playback0PROG–CD/USB: programs tracks

–

press and

RDS/NEWS

– Tuner: programs preset radio stations

– Tuner: selects RDS (Radio

ÉÅ

USB source

BBBB

ECO POWER);

In standby or Eco Power mode:

hold to toggle between Standby and ECO

POWER mode (power-saving mode)

– Then select the desired function (for

example

press briefly to switch the set on or off (standby/

Source buttons

USB

selects

TIMER

for more than 2 seconds)

information

– CD/USB/AUX: activates/deactivates news

In standby/Eco-power mode: switches the set

on and selects USB source.

CLOCK–Clock:

– enters the timer setting mode (press and hold

switches the set

source

selects CD

on and selects CD source.

In standby/Eco-power mode:

enters the clock

In standby mode:

- displays the set time

setting mode (press and hold for more

than 2 seconds)

switches the set

TUNER source and toggles between the

TUNER

selects

wavebands: FM and MW

In standby/Eco-power mode:

TUNER/Audio CD/AUX: switches between

clock display and playback display

–

source

TUNER

on and selects

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