CMT-BX70DBI, HCD-BX70DBI - Sony Audio Service Manual (repair manual)

2009B00-1

© 

2009.02

Model Name Using Similar Mechanism

HCD-EC68

Base Unit Name

BU-K6BD90-WOD

Optical Pick-up Block Name

KSM-213DCP

•  HCD-BX70DBi is the amplifi er, CD player, tuner 

and iPod section in CMT-BX70DBi.

iPod is a trademark of Apple Inc., registered in the U.S. and other countries.

MPEG Layer-3 audio coding technology and patents licensed from Fraunhofer 
IIS and Thomson.

All other trademarks and registered trademarks are of their respective holders.
In this manual,

TM

and

®

marks are not specified.

DIN power output (rated):
18 + 18 W (6 ohms at 1 kHz, DIN)
Continuous RMS power output (reference): 25 + 25 W (6 ohms at 1 kHz,
10% THD)
Music power output (reference): 38 + 38 W (6 ohms at 1 kHz, 10% THD)

AUDIO IN (stereo mini jack): voltage 250 mV, impedance 47 kilohms

PHONES (stereo mini jack): accepts headphones of 8 ohms or more
SPEAKER: accepts impedance of 6 to 16 ohms

System: Compact disc and digital audio system
Laser Diode Properties

Emission Duration: Continuous
Laser Output*: Less than 44.6μW
*

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

This output is the value measurement at a distance of 200mm from the

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

DAB tuner section:

Frequency range*
Band-III: 174.928 (5A) –  239.200 (13F) MHz
* For details, see “DAB frequency table” below.
Antenna: FM/DAB lead antenna
Antenna terminal: 75 ohms, F female

FM stereo, FM/AM superheterodyne tuner
FM tuner section:

Tuning range: 87.5 – 108.0 MHz (50 kHz step)
Antenna: FM/DAB lead antenna
Antenna terminals: 75 ohms unbalanced
Intermediate frequency: 10.7 MHz

AM tuner section:

Tuning range: 531 – 1,602 kHz (with 9 kHz tuning interval)
Antenna: AM loop antenna, external antenna terminal
Intermediate frequency: 450 kHz

DAB frequency table (Band-III)

174.928 MHz

5A

209.936 MHz

10A

176.640 MHz

5B

211.648 MHz

10B

178.352 MHz

5C

213.360 MHz

10C

180.064 MHz

5D

215.072 MHz

10D

181.936 MHz

6A

216.928 MHz

11A

183.648 MHz

6B

218.640 MHz

11B

185.360 MHz

6C

220.352 MHz

11C

187.072 MHz

6D

222.064 MHz

11D

188.928 MHz

7A

223.936 MHz

12A

190.640 MHz

7B

225.648 MHz

12B

192.352 MHz

7C

227.360 MHz

12C

194.064 MHz

7D

229.072 MHz

12D

195.936 MHz

8A

230.784 MHz

13A

197.648 MHz

8B

232.496 MHz

13B

199.360 MHz

8C

234.208 MHz

13C

201.072 MHz

8D

235.776 MHz

13D

202.928 MHz

9A

237.488 MHz

13E

204.640 MHz

9B

239.200 MHz

13F

206.352 MHz

9C

208.064 MHz

9D

– Continued on next page –

  .............................................   3

  ..................................................................   4

3-1.   Disassembly Flow ...........................................................   6
3-2.   Panel (Side L/R) ..............................................................   7
3-3.   Top Panel Block ..............................................................   7
3-4.   TOP KEY Board, IP Board, Panel Top (IP) ....................   8
3-5.   Front Panel Block ...........................................................   8
3-6.   Rear Panel Block ............................................................   9
3-7.   Panel (Rear) ....................................................................   9
3-8.   AMP Board Block ...........................................................   10
3-9.   POWER Board Block .....................................................   10
3-10.  MAIN Board ...................................................................   11
3-11.  DAB Board, Module (DAB Tuner) ................................   11
3-12.  Loading Mechanism Block .............................................   12
3-13.  Base Unit .........................................................................   12
3-14.  Belt ..................................................................................   13
3-15.  OP Base Assy (KSM-213D) ...........................................   13

TEST  MODE 

 ............................................................   14

ELECTRICAL  CHECKS 

 ......................................   16

6-1.  Block Diagram - CD SERVO Section - ..........................   17
6-2.  Block Diagram - iPod, TUNER, DAB Section - ............   18
6-3.  Block Diagram - MAIN Section - ...................................   19
6-4. Block 

Diagram 

 

- PANEL, POWER SUPPLY Section - ...........................   20

6-5.  Printed Wiring Boards - CD Section - ............................   22
6-6.  Schematic Diagram - CD Board - ...................................   23
6-7.  Printed Wiring Board - DAB Board - .............................   24
6-8.  Schematic Diagram - DAB Board - ................................   25
6-9.  Printed Wiring Board - IP Board - ..................................   26
6-10.  Schematic Diagram - IP Board - .....................................   27
6-11.  Printed Wiring Boards - MAIN Section - .......................   28
6-12.  Schematic Diagram - MAIN Section (1/3) - ...................   29
6-13.  Schematic Diagram - MAIN Section (2/3) - ...................   30
6-14.  Schematic Diagram - MAIN Section (3/3) - ...................   31
6-15. Printed Wiring Boards 
 

- AMP/HEADPHONE Section - .....................................   32

6-16.  Schematic Diagram - AMP/HEADPHONE Section - ....   33
6-17.  Printed Wiring Boards - PANEL Section - .....................   34
6-18.  Schematic Diagram - PANEL Section - ..........................   35
6-19.  Printed Wiring Board - POWER Board - ........................   36
6-20.  Schematic Diagram - POWER Board - ..........................   37

7-1. Panel 

Sectiom 

.................................................................  45

7-2.  Top Panel Section ...........................................................   46
7-3.  Front Panel Section .........................................................   47
7-4.  MAIN Board Section ......................................................   48
7-5.  POWER Board Section ...................................................   49
7-6.  Loading Mechanism Section ..........................................   50
7-7.  Base Unit Section (BU-K6BD90-WOD) ........................   51

  ..............................   52

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.

FLEXIBLE  CIRCUIT  BOARD  REPAIRING
• 

Keep the temperature of soldering iron around 270 °C during 
repairing.

• 

Do not touch the soldering iron on the same conductor of the 
circuit board (within 3 times).

• 

Be careful not to apply force on the conductor when soldering 
or unsoldering.

COMPONENTS  IDENTIFIED  BY  MARK  0  OR  DOTTED  LINE  
WITH  MARK  0  ON  THE  SCHEMATIC  DIAGRAMS  AND  IN  
THE  PARTS  LIST  ARE  CRITICAL  TO  SAFE  OPERATION.
REPLACE  THESE  COMPONENTS  WITH  SONY  PARTS 

Compatible iPod models:

iPod touch

iPod nano 3rd

generation

(video)

iPod classic

iPod nano 2nd

generation

(aluminum)

iPod 5th

generation

(video)

iPod nano 1st

generation

iPod 4th

generation

(color display)

iPod 4th

generation

iPod mini

Power requirements: 230 V AC, 50/60 Hz
Power consumption: 63 watts
Dimensions (w/h/d) (excl. speakers): Approx. 215 × 140 × 298 mm
Mass (excl. speakers):

Design and specifications are subject to change without notice.

Approx. 3.9 kg

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

This appliance is classifi ed as 
a CLASS 1 LASER product.
This marking is located on the 
rear or bottom exterior.

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 electrostat-
ic 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.

ANTITHEFT  UNLOCK  MODE
Procedure:
1.  Press the [

?/1

] button to turn the power on.

2.  Press the [FUNCTION] button to select “CD”.
3.  Press two buttons of [

x/

CANCEL] and [

A

] for 5 seconds.

4.  The message “UNLOCKED” is displayed on the fl uorescent 

indicator tube and the disc tray is unlocked.

Note: When “LOCKED” is displayed, the tray lock is not released by 

turning power on/off with the [?/1] button.

Note: Please insert a screwdriver after removing the panel (side L).
 

About disassembly of the panel (side L), please refer to “3-2. Panel (Side L/R)” (page 7).

This section is extracted 
from instruction manual.

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 supplied R6 (size AA) batteries, 

 side 

first, matching the polarities shown below. 

Notes on using the remote
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 

 (power) .

Select the clock set mode.
Press TIMER MENU . If the current mode appears 
on the display, press 

/  repeatedly to select 

“CLOCK SET?” 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.
To display the clock when the system is off, press 
DISPLAY . The clock is displayed for about 8 
seconds.

When you turn on the system for the first time after 
you purchase the system, DAB Automatic Scan starts 
automatically and creates a list of available services.
If you want to run the DAB Automatic Scan again, 
perform the procedure below.

Press DAB AUTO SCAN  on the unit.
“Auto Scan?” and “Push Enter” appear.

Press 

(enter) .

Scanning begins. “

” appears. Depending on 

the DAB services available in your area, scanning may 
take a few minutes.

When scanning is complete, a list of available services 
is created.

Notes
If your country or region does not support DAB broadcast, “No 

Service” appears.

Do not press any button on the unit or the remote during DAB 

Automatic Scan. If scanning is interrupted, run the DAB Automatic 
Scan again.

If you move to another area, repeat this procedure to store the 

stations for your new area.

This procedure clears all previously stored presets.

Before unplugging the DAB antenna, make sure the system is turned 

off to preserve your own DAB settings.

This tuner does not support data services.

Insert an iPod Dock Adapter into the unit’s connector 
before use.
For details on the supplied iPod Dock Adapters, refer to 
the instructions supplied with the Dock Adapters.

To remove the iPod Dock Adapter, pull it up with your 
fingernail or a flat object using the slot inside the adapter.

Slot

Press VOLUME +/

 (or VOL +/ on the unit) .

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

DSGX  on the unit.

Set the sound effect

EQ  repeatedly to select 
“BASS” or “TREBLE,” and 
then press +/

  repeatedly 

to adjust the level.

Select the CD function.
Press FUNCTION +/

 (or FUNCTION on the unit) 

 repeatedly.

Place a disc.
Press 

 (open/close)  on the unit, and place a disc 

with the label side up on the disc tray.

To close the disc tray, press 

 (open/close)  on the 

unit.
Do not force the disc tray closed with your finger, as 
this may damage the unit.

Start playback.
Press 

 (play) (or CD  (play/pause) on the 

unit) .

Pause playback

 (pause) (or CD  (play/
pause) on the unit) .
To resume play, press the button 
again.

Stop playback

 (stop) (or /CANCEL on the 
unit) .

Select a folder on an 
MP3 disc

 +/

 (select folder) .

Select a track or file

/ (go back/go forward) 

.

Find a point in a 
track or file

Hold down 

/ (rewind/

fast forward)  during playback, 
and release the button 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 normal (shuffle) play.

Notes on Repeat 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.

Notes on playing MP3 discs
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 255 (including the root folder).
MP3 files is 511.
MP3 files and folders that can be contained on a single disc is 512.
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.

Notes on playing multisession discs
If the disc begins with a CD-DA (or MP3) session, it is recognized as 

a CD-DA (or MP3) disc, and other sessions are not played back.

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

disc.

Before you can receive DAB, you must complete the 
DAB Automatic Scan procedure (see “Before using the 
system”). 

Select “TUNER DAB,” “TUNER FM” or “TUNER AM.”
Press FUNCTION +/

 (or FUNCTION on the unit) 

 repeatedly. You can also select DAB directly by 
pressing DAB AUTO SCAN  on the unit.

Select the tuning mode.
Press TUNING MODE  repeatedly until “AUTO” 
appears. 

Tune in the desired station.
Press +/

 (or TUNE +/ on the unit) . Scanning 

stops automatically when a station is tuned in, and 
then “TUNED” and “STEREO” (for stereo programs 
only) appear.

When you tune in a DAB station or an FM station that 
provides RDS services, the service name or station 
name appears on the display.

Press 

 (stop) (or /CANCEL on the unit) .

If “TUNED” does not appear and the scanning does not 
stop, press TUNING MODE  repeatedly until “AUTO” 
and “PRESET” disappear, and then press +/

 (or TUNE 

+/

 on the unit)  repeatedly to tune in the desired 

station.

Press FM MODE  repeatedly until “MONO” appears 
to turn off stereo reception.

Notes on listening to DAB stations
When tuning in a DAB station, it may take a few seconds before you 

hear any sound.

Primary service is automatically received when secondary service 

ends.

Select the iPod function.
Press FUNCTION  +/

 (or FUNCTION on the unit) 

 repeatedly.

Place the iPod.

Start playback.
Press 

 (play) (or iPod  (play/pause) on the 

unit) .

You can control your iPod with the following buttons on 
the remote or unit.

Pause playback

 (pause) (or iPod 
(play/pause) on the unit)  or 



(stop) .

Scroll up/down the 
iPod menus

/ . You can scroll up or 
down the iPod menus much like 
the Click Wheel operations of 
the iPod or the drag up-or-down 
operations of the iPod touch.

Select a track 
or chapter of 
audiobook/podcast

/ (go back/go forward) 

. To fast-forward or fast-
rewind, hold down the button.

Choose the selected 
item

 /

(enter) (or ENTER on 

the unit) . You can choose the 
selected item much like the center 
button on the iPod or the touch 
operation of the iPod touch.

Find a point in a 
track or chapter of 
audiobook/podcast

/ (fast rewind/fast 
forward)  during playback, and 
release the button at the desired 
point.

Return to the 
previous menu or 
select a menu

 /TOOL MENU / 
(return) . You can return to the 
previous menu or select a menu 
much like the Menu button on 
the iPod or the touch operation 
of the iPod touch.

You can use the system as a battery charger for the iPod 
when the system is both on and off.
The charging begins when the iPod is placed on the unit’s 
connector . The charging status appears in the iPod 
display. For details, see the user’s guide of your iPod.

Remove the iPod. If you stop charging the iPod when 
the system is off, press DISPLAY  until the clock 
disappears in the display.

Notes
When placing or removing the iPod, handle the iPod in the same 

angle as that of the iPod connector  on the unit and do not twist 
or sway the iPod to prevent connector damage.

Do not carry the unit with an iPod set on the connector. Doing so 

may cause a malfunction.

When placing or removing the iPod, brace the unit with one hand 

and take care not to press the controls of the iPod by mistake.

Before disconnecting the iPod, pause playback.

While playing video, you cannot use / . You can fast 

rewind (fast forward) by holding down 

/ .

To change the volume level, use VOLUME +/ (or VOL +/ on the 

unit) . The volume level does not change even if adjusted on the 
iPod.

This system is designed for iPod only. You cannot connect any other 

portable audio players.

To use an iPod, refer to the user’s guide of your iPod.

Sony cannot accept responsibility in the event that data recorded to 

iPod is lost or damaged when using an iPod with this unit.

Change 
information on the 
display

1)

DISPLAY  repeatedly when the 
system is on.

Check the clock 
when the system 
is off

2)

DISPLAY  when the system is 
off

3)

. The clock is displayed for 8 

seconds.

1)

For example, you can view CD/MP3 disc information, such as;
track or file number during normal play.
track or file name (“ ”) during normal play.
artist name (“ ”) during normal play.
album or folder name (“

”) during normal play.

total playing time while the player is stopped.

You can also view DAB station information such as the service 
name, channel label, preset number, frequency, DLS (Dynamic Label 
Segment), or ensemble label.

2)

The clock is displayed continuously while the iPod is being charged. 
To turn off the clock display, press DISPLAY  (See “To stop 
charging the iPod”).

3)

The STANDBY indicator  on the unit lights up when the system is 
off.

Notes on the display information
Characters that cannot be displayed appear as “_”.

The following are not displayed:

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

The following are not displayed correctly:

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

Level 2 or Joliet in the expansion format.

The following is displayed:

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

2 tags are used (up to 62 characters).

up to 8 characters of service name, up to 128 characters of DSL 

(Dynamic Label Segment) and up to 16 characters of ensemble 
label.

Connect headphones to the PHONES jack  on the 
unit.

Connect additional audio 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.