CMT-NEZ7DAB, HCD-NEZ7 - Sony Audio Service Manual (repair manual)

2007F05-1
© 2007.06

– Continued on next page –

AEP Model

UK Model

•

HCD-NEZ7 is the amplifier, CD player, tape deck and
tuner section in CMT-NEZ7DAB.

Model Name Using Similar Mechanism

HCD-NEZ3

CD Section

Base Unit Name

BU-K7BD81D2

Optical Pick-up Block Name

KSM-213EDP

TAPE Section

Model Name Using Similar Mechanism

HCD-NEZ3

Tape Transport Mechanism Type

CMAL5Z231

DIN power output (rated): 11 + 11 W (6 ohms at 

1 kHz, DIN)

Continuous RMS power output (reference):

15 + 15 W (6 ohms at 
1 kHz, 10% THD)

Music power output (reference):

28 + 28 W

Inputs
AUDIO IN:

Sensitivity 250 mV, 
impedance 47 kilohms

Outputs
PHONES:

Accepts headphones with 
an impedance of 8 ohms or 
more

SPEAKER:

Accepts impedance of 6 to 
16 ohms.

Laser Diode Properties

Emission duration: 
continuous
Laser Output: Less than 
44.6 

µ

W

(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

Recording system

4-track 2-channel, stereo

DAB tuner section

Frequency range
Band-III:

174.928 (5A) – 
239.200 (13F) MHz

L-Band:

1,452.960 MHz (LA) – 
1,490.624 MHz (LW)
(L-Band is not available 
for the UK model.)

* For details, see “DAB frequency table” below.

Aerial terminal

75 ohms, F female

FM stereo, FM/AM superheterodyne tuner

FM tuner section

Tuning range

87.5 – 108.0 MHz

Aerial

FM lead aerial

Aerial terminals

75 ohms unbalanced

Intermediate frequency

10.7 MHz

AM tuner section

Tuning range

531 – 1,602 kHz 
(with the tuning interval 
set at 9 kHz) 

Aerial

AM loop aerial, external 
aerial terminal

Intermediate frequency

450 kHz 

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

2

•

Never reuse a disconnected chip component.

•

Notice that the minus side of a tantalum capacitor may be

damaged by heat.

•

Keep the temperature of the 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.

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

 0

0

The following caution label is located inside the unit.

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

1,452.960 MHz

LA

1,454.672 MHz

LB

1,456.384 MHz

LC

1,458.096 MHz

LD

1,459.808 MHz

LE

1,461.520 MHz

LF

1,463.232 MHz

LG

1,464.944 MHz

LH

1,466.656 MHz

LI

1,468.368 MHz

LJ

1,470.080 MHz

LK

1,471.792 MHz

LL

1,473.504 MHz

LM

1,475.216 MHz

LN

1,476.928 MHz

LO

1,478.640 MHz

LP

1,480.352 MHz

LQ

1,482.064 MHz

LR

1,483.776 MHz

LS

1,485.488 MHz

LT

1,487.200 MHz

LU

1,488.912 MHz

LV

1,490.624 MHz

LW

L-Band is not available for the UK model.

Power requirements

AC 230 V, 50/60 Hz

Power consumption

50 W
0.3 W (in Power Saving 
Mode)

Dimensions (w/h/d) 

Approx. 164 

×

235 

×

265 mm

Mass  

Approx. 

3.6 

kg

Design and specifications are subject to change 
without notice.

3

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

4

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

6

3-1. Disassembly Flow .......................................................... 8
3-2. Cabinet ............................................................................ 8
3-3. Cabinet (Top) Section .................................................... 9
3-4. Base Unit (BU-K7BD81D2) ........................................... 9
3-5. Front Panel Section ........................................................ 1 0
3-6. Mechanical Deck (CMAL5Z231) .................................. 1 0
3-7. MAIN Board .................................................................... 1 1
3-8. Module (DAB) Tuner, Tuner Unit .................................... 1 1

.............................................................. 12

....................... 13

......................... 13

7-1.

Block Diagram – CD SERVO Section – ......................... 14

7-2.

Block Diagram – AUDIO Section – ................................ 15

7-3.

Block Diagram – PANEL/POWER SUPPLY Section – . 16

7-4.

Printed Wiring Board – CD Board – ............................... 18

7-5.

Schematic Diagram – CD Board – .................................. 19

7-6.

Printed Wiring Boards – MAIN Section – ...................... 20

7-7.

Schematic Diagram – SELECTOR Board – ................... 21

7-8.

Schematic Diagram – MAIN Section (1/2) – .................. 22

7-9.

Schematic Diagram – MAIN Section (2/2) – .................. 23

7-10. Printed Wiring Board – PANEL Board – ........................ 25
7-11. Schematic Diagram – PANEL Board (1/2) – .................. 26
7-12. Schematic Diagram – PANEL Board (2/2) – .................. 27
7-13. Printed Wiring Board – POWER Board – ....................... 28
7-14. Schematic Diagram – POWER Board – .......................... 29

8-1.

Cabinet Section ................................................................ 34

8-2.

Mechanical Deck Section ................................................ 35

8-3.

Panel Board Section ........................................................ 36

8-4.

Cabinet (Top) Section ...................................................... 37

8-5.

Chassis Section ................................................................ 38

................................ 39

4

The laser diode in the optical pick-up block may suffer electrostatic
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 flexible board is easily damaged and should be handled with
care.

S820

The laser beam on this model is concentrated so as to be focused on
the disc reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.

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)

During normal operation of the equipment, emission of the laser
diode is prohibited unless the upper lid is closed while turning ON
the S820. (push switch type)
The following checking method for the laser diode is operable.

•

1. Open the upper lid.
2. Push the S820 as shown in Fig.1.

Do not push the detection lever strongly, or it may be bent or damaged.

3. Press the[CD      ]button.
4. Check the object lens for confirming 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 3
times along with inward motion for the focus search.

u

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 viscou-s (sticky, less prone to flow)

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.

There are two types of MODULE (DAB TUNER) in UK model.
Replace the MODULE (DAB TUNER) after confirming the type of
the MODULE (DAB TUNER) reffering to the following table.

Former Type

New Type

MODULE

(DAB TUNER)

Part No. 1-479-310-21

Part No. 1-479-954-21

COAXIAL (F TYPE)

CONNECTOR

including MODULE (DAB TUNER)

–

Part No. 1-820-441-11