CMT-EH15, HCD-EH15 - Sony Audio Service Manual (repair manual)

2010C05-1

© 

2010.03

• HCD-EH15 is the amplifi er, CD player, 

tape deck and tuner section in CMT-EH15.

CD 
Section

Model Name Using Similar Mechanism

NEW

Base Unit Name

BU-K8BD90-WOD

Optical Pick-up Name

KSM-213CDP

Tape 
Section

Model Name Using Similar Mechanism

NEW

Tape Transport Mechanism Type

MF-EH10

European and Russian models:

DIN power output (rated): 4 + 4 W (4 ohms at 1 kHz, DIN)
Continuous RMS power output (reference): 5 + 5 W (4 ohms at 1 kHz, 
10% THD)
Music power output (reference): 7 + 7 W

Other models:

DIN power output (rated): 4 + 4 W (4 ohms at 1 kHz, DIN)
Continuous RMS power output (reference): 5 + 5 W (4 ohms at 1 kHz, 
10% THD)

Inputs

AUDIO IN (stereo mini jack): Sensitivity 800 mV, impedance 47 kilohms

Outputs

PHONES (stereo mini jack): Accepts headphones with an impedance of 
8 ohms or more
SPEAKER: Accepts impedance of 4 ohms

System: Compact disc and digital audio system
Laser Diode Properties

Emission Duration: Continuous
Laser Output*: Less than 44.6μW
* This output is the value measurement at a distance of 200 mm from the 

objective lens surface on the Optical Pick-up Block with 7 mm aperture.

Frequency response: 20 Hz   20 kHz
Signal-to-noise ratio: More than 90 dB
Dynamic range: More than 90 dB

Recording system: 4-track 2-channel, stereo

FM stereo, FM/AM superheterodyne tuner
Antenna:

FM lead antenna
AM loop antenna

FM tuner section:

Tuning range
Canadian model: 87.5   108.0 MHz (100 kHz step)
Other models: 87.5   108.0 MHz (50 kHz step)
Intermediate frequency: 10.7 MHz

AM tuner section:

Tuning range
Canadian and Latin American models:
530   1,710 kHz (with 10 kHz tuning interval)
531   1,710 kHz (with 9 kHz tuning interval)
European and Russian models:
531   1,602 kHz (with 9 kHz tuning interval)
Australian model:
531   1,710 kHz (with 9 kHz tuning interval)
530   1,710 kHz (with 10 kHz tuning interval)
Other models:
531   1,602 kHz (with 9 kHz tuning interval)
530   1,610 kHz (with 10 kHz tuning interval)
Intermediate frequency: 450 kHz

Power requirements:

Canadian model: AC 120 V, 60 Hz

Eu

Mexican model: AC 120 V, 60 Hz

ropean and Russian models: AC 230 V, 50/60 Hz

Australian model: AC 230   240 V, 50/60 Hz
Argentine and Thai models: AC 220 V, 50/60 Hz
Brazilian model: AC 127 or 220 V, 50/60 Hz
Korean model: AC 220 V, 60 Hz
Taiwan model: AC 120 V, 50/60 Hz
Other models: AC 110   120 or 220   240 V, 50/60 Hz
Adjustable with voltage selector

Power consumption: 25 W
Dimensions (w/h/d) (excl. speakers): Approx. 155 × 241 × 224.6 mm
Mass (excl. speakers): Approx. 2.2 kg

Design and specifications are subject to change without notice.

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

3

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

4

3-1. Disassembly 

Flow 

...........................................................   6

3-2.  Rear Cabinet Block .........................................................   6
3-3.  Front Cabinet Block, Top Cabinet Block, 
 MAIN 

Board 

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

7

3-4.  MF-EH10 (Tape Mechanism Deck), Cassette Lid ..........   7
3-5.  Base Unit Block (BU-K8BD90-WOD) ..........................   8
3-6.  Optical Pick-up Block (KSM-213CDP) .........................   8

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

9

 ......................   10

........................  10

7-1.  Printed Wiring Board - CD Board - ................................   14
7-2.  Schematic Diagram - CD Board - ...................................   15
7-3.  Printed Wiring Board - PANEL Board - .........................   16
7-4.  Schematic Diagram - PANEL Board - ............................   17
7-5.  Schematic Diagram - MAIN Section (1/2) - ...................   18
7-6.  Schematic Diagram - MAIN Section (2/2) - ...................   19
7-7.  Printed Wiring Boards - MAIN Section - .......................   20

8-1. Overall 

Section 

...............................................................  27

8-2.  Front Cabinet Section .....................................................   28
8-3.  Top Cabinet Section ........................................................   29
8-4.  Base Unit Section (BU-K8BD90-WOD) ........................   30

  ..............................   31

Note: Refer to supplement-1 for the MAIN board of printed wiring 

board, schematic diagram and electrical parts list of AEP, 
Brazilian and Thai models.

Notes on chip component replacement
• 

Never reuse a disconnected chip component.

• 

Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.

This appliance is classified 
as a CLASS 1 LASER 
product. This marking 
is located on the rear 
exterior.

0  OR  DOTTED  LINE  

0  ON  THE  SCHEMATIC  DIAGRAMS  AND  IN  

0  SUR  

CAUTION
Use of controls or adjustments or performance of procedures other than 
those specifi ed herein may result in hazardous radiation exposure.

UNLEADED  SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with 

the lead free mark due to their particular size)

Unleaded solder has the following characteristics.
•  Unleaded solder melts at a temperature about 40 °C higher 

than ordinary solder.

 

Ordinary soldering irons can be used but the iron tip has to be 
applied to the solder joint for a slightly longer time.

 

Soldering irons using a temperature regulator should be set to 
about 350 °C.
Caution:  The printed pattern (copper foil) may peel away if the 

heated tip is applied for too long, so be careful!

• Strong 

viscosity

 

Unleaded solder is more viscous (sticky, less prone to fl ow) 
than ordinary solder so use caution not to let solder bridges 
occur such as on IC pins, etc.

•  Usable with ordinary solder
 

It is best to use only unleaded solder but unleaded solder may 
also be added to ordinary solder.

The laser diode in the optical pick-up block may suffer electro-
static break-down because of the potential difference generated by 
the charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also 
use the procedure in the printed matter which is included in the 
repair parts.
The fl exible board is easily damaged and should be handled with 
care.

NOTES  ON  LASER  DIODE  EMISSION  CHECK
The laser beam on this model is concentrated so as to be focused 
on the disc refl ective surface by the objective lens in the optical 
pickup block. Therefore, when checking the laser diode emission, 
observe from more than 30 cm away from the objective lens.

LASER  DIODE  AND  FOCUS  SEARCH  OPERATION  
CHECK
During normal operation of the equipment, emission of the laser
diode is prohibited unless the upper lid is closed while turning on 
the SW750. (push switch type)
The following checking method for the laser diode is operable.
• Method
  Emission of the laser diode is visually checked.
  1.  Open the upper lid.
  2.  Push the SW750 as shown in Fig.1.

 Note:  Do not push the detection lever strongly, or it may be bent or 

damaged.

  3.  Check the object lens for confi rming normal emission of the 

laser diode. If not emitting, there is a trouble in the automatic 
power control circuit or the optical pick-up.

    In this operation, the object lens will move up and down 2 

times along with inward motion for the focus search.

Canadian and Mexican 
models

AC 120 V, 60 Hz

AEP, Russian and UK 
models

AC 230 V, 50/60 Hz 

Australian model

AC 230 – 240 V, 50/60 Hz

Argentina and Thai 
models

AC 220 V, 50/60 Hz

Korean model

AC 220 V, 60 Hz

Taiwan model

AC 120 V, 50/60 Hz

Singapore, Chilean and 
Peruvian models

AC 110 – 120 or 220 – 240 V, 
50/60 Hz

Brazilian model

AC 127 or 220 V, 50/60 Hz

This section is extracted 
from instruction manual.

Open the tape 
section lid.

This manual mainly explains operations using the 
remote, but the same operations can also be performed 
using the buttons on the unit having the same or similar 
names.

Slide and remove the battery compartment lid 



, and 

insert the two R6 (size AA) batteries (not supplied), 



side first, matching the polarities shown below.

With normal use, the batteries should last for about six months.

Do not mix an old battery with a new one or mix different types of 

batteries.

If you do not use the remote for a long period of time, remove the 

batteries to avoid damage from battery leakage and corrosion.

Use buttons on the remote to set the clock.

Turn on the system.

Press 

 (on/standby) 



.

Select the clock set mode.

Press CLOCK/TIMER SET 



. If the current mode 

appears, press 

/



 repeatedly to select 

“CLOCK,” and then press ENTER 



.

Set the time.

Press 

/



 repeatedly to set the hour, and 

then press ENTER 



. Use the same procedure to set 

the minutes.
The clock settings are lost when you disconnect the 
power cord or if a power failure occurs.

Press the following buttons (or press FUNCTION 



repeatedly).

CD

CD



.

Tuner

TUNER/BAND 



.

Tape

FUNCTION 



repeatedly until “TAPE” 
appears.

Component* (connected 
using an audio cord)

AUDIO IN 



.

* If the component has the AVLS (Automatic Volume Limiter System) 

or BASS BOOST function, turn off the function to avoid distorted 
sound from the speakers.

Press VOLUME +/

 (or turn the VOLUME control on 

the unit) 



.

Generate a more dynamic 
sound (Dynamic Sound 
Generator X-tra)

DSGX



 on the unit.

Set the sound effect

EQ



.

Select the CD function.

Press CD (or FUNCTION repeatedly) 



.

Place a disc.

Press 

PUSH OPEN/CLOSE on the unit, and place a 

disc with the label side up on the CD compartment.
To close the CD compartment, press 

PUSH OPEN/

CLOSE on the unit.

PUSH OPEN/CLOSE

Start playback.

Press 

 (play) (or CD/ (play/pause) on the unit) 



.

Pause playback

 (pause) (or CD/ on the 
unit) 



. To resume play, press 

it again.

Stop playback

 (stop) 



.

Select a folder on an 
MP3 disc

 +/

 (select folder) 



.

Select a track or file

/ (go back/go forward) 
(

/ on the unit) 



.

Find a point in a 
track or file

Hold down 

/ (rewind/

fast forward) 



 during playback, 

and release it at the desired point.

Select Repeat Play

REPEAT 



 repeatedly until 

“REP” or “REP1” appears.

Press PLAY MODE 



 repeatedly while the player is 

stopped. You can select normal play (“

” for all MP3 

files in the folder on the disc), shuffle play (“SHUF” or
“

 SHUF*”), or program play (“PGM”).

* When playing a CD-DA disc, 

 (SHUF) Play performs the same 

operation as SHUF Play.

All tracks or files on a disc are played repeatedly up to five times.

“REP1” indicates that a single track or file is repeated until you stop 

it.

Do not save other types of tracks or files or unnecessary folders on a 

disc that has MP3 files.

Folders that have no MP3 files are skipped.

MP3 files are played back in the order that they are recorded onto 

the disc.

The system can only play MP3 files that have a file extension of 

“.MP3”.

If there are files on the disc that have the “.MP3” file extension, 

but that are not MP3 files, the unit may produce noise or may 
malfunction.

The maximum number of:

folders is 150 (including the root folder).
MP3 files is 255.
MP3 files and folders that can be contained on a single disc is 256.
folder levels (the tree structure of files) is 8.

Compatibility with all MP3 encoding/writing software, recording 

device, and recording media cannot be guaranteed. Incompatible 
MP3 discs may produce noise or interrupted audio or may not play 
at all.

If the disc begins with a CD-DA (or MP3) session, it is recognized 

as a CD-DA (or MP3) disc, and playback continues until another 
session is encountered.

A disc with a mixed CD format is recognized as a CD-DA (audio) 

disc.

Select “FM” or “AM.”

Press TUNER/BAND 



 repeatedly.

Select the tuning mode.

Press TUNING MODE 



 repeatedly until “AUTO” 

appears.

Tune in the desired station.

Press +/

 (or TUNING +/ on the unit) 



.

Scanning stops automatically when a station is tuned 
in. When you tune in a station that provides RDS 
services, the station name appears.

To stop automatic scanning, press 

 (stop) .

Press TUNING MODE 



 repeatedly until “MANUAL” 

appears, and then press +/

 (or TUNING +/ on the 

unit) 



 repeatedly to tune in the desired station.

Press FM MODE 



 repeatedly until “MONO” appears 

to turn off stereo reception.

Use buttons on the unit to play a tape.

Select the tape function.

Press FUNCTION 



 repeatedly.

Insert a tape.

Press 

 (stop/eject) 



, and insert the tape into the 

cassette holder. Make sure there is no slack in the tape 
to avoid damaging the tape or the tape deck.

Start playback.

Press 

 (play) 



.

Pause playback

 (pause) 



. To resume play, press 

it again.

Stop playback

 (stop/eject) 



.

Rewind or fast 
forward*

/ (rewind/fast forward) 



.

* Be sure to press 

 (stop/eject)  after the tape has been wound 

or rewound to the end.

Do not turn off the system during playback or recording.

Information on 
the display

1)

DISPLAY 



 repeatedly when the 

system is on.

Display mode 
(Clock)

DISPLAY 



 when the system is 

off

2)

. The clock is displayed for eight 

seconds.

1)

For example, you can view CD/MP3 disc information, such as the 
track or file number or folder name during normal play, or the total 
play time while the player is stopped.

2)

The STANDBY indicator  lights up when the system is turned off.

The following are not displayed;

total playing time for a CD-DA disc depending on the play mode.
total playing time for an MP3 disc.
remaining playing time for a track and an MP3 file.

The following are not displayed correctly;

elapsed playing time of an MP3 file encoded using VBR (variable 

bit rate).

folder and file names that do not follow either ISO9660 Level 1,

Level 2 or Joliet in the expansion format.

The following are displayed;

ID3 tag information for MP3 files when ID3 version 1 and 

version 2 tags are used.

up to 15 characters of ID3 tag information using uppercase letters 

(A to Z), numbers (0 to 9), and symbols (‘< > * + , – / @ [ \ ] _).

Connect headphones to the PHONES jack 



 on the 

unit.

Connect additional audio source component to the 
AUDIO IN jack 



 on the unit using an audio analog 

cord (not supplied). Turn down the volume on the 
system, and then select the AUDIO IN function.