HCD-EC98P, MHC-EC98P, MHC-EC98PI - Sony Audio Service Manual (repair manual). Page 3

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

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

3-1. Disassembly 

Flow 

...........................................................  10

3-2.  Side Panel (L)/(R) ...........................................................   11
3-3. Panel 

(Top) 

......................................................................  11

3-4. MAIN 

Board 

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

3-5.  Front Panel Block (Australian model) ............................   12
3-6.  Front Panel Block (US and Canadian models) ...............   13
3-7.  Back Panel Block ............................................................   13
3-8.  3 CD Mechanism Block (Australian model) ..................   14
3-9.  Base Unit (Australian model) .........................................   14
3-10.  1 CD Mechanism Block (US and Canadian models) .....   15
3-11.  Base Unit (US and Canadian models) ............................   15
3-12.  Belt (US and Canadian models) ......................................   16
3-13.  Belt (Australian model) ..................................................   16
3-14.  OP Base Assy (KSM-213D) ...........................................   17

TEST  MODE 

 ............................................................   18

ADJUSTMENTS 

 ........................   22

6-1.  Block Diagram - CD SERVO, TUNER Section - ...........   25
6-2.  Block Diagram - MAIN Section - ...................................   26
6-3.  Printed Wiring Board - CD Board - ................................   28
6-4.  Schematic Diagram - CD Board - ...................................   29
6-5.  Printed Wiring Boards - MAIN Section - .......................   30
6-6.  Schematic Diagram - MAIN Section (1/3) - ...................   31
6-7.  Schematic Diagram - MAIN Section (2/3) - ...................   32
6-8.  Schematic Diagram - MAIN Section (3/3) - ...................   33
6-9.  Printed Wiring Board - HI AMP Board - ........................   34
6-10.  Schematic Diagram - HI AMP Board - ...........................   34
6-11.  Printed Wiring Board - LOW AMP Board - ...................   35
6-12.  Schematic Diagram - LOW AMP Board - ......................   35
6-13.  Printed Wiring Board - PANEL Board - .........................   36
6-14.  Schematic Diagram - PANEL Board - ............................   37
6-15.  Printed Wiring Boards - KEY Section - ..........................   38
6-16.  Schematic Diagram - KEY Section - ..............................   38
6-17.  Printed Wiring Board - PT Board - .................................   39
6-18.  Schematic Diagram - PT Board - ....................................   39
6-19. Printed Wiring Board 
 

- MOTOR Board (US and Canadian models) - ..............   40

6-20. Schematic Diagram 
 

- MOTOR Board (US and Canadian models) - ..............   40

7-1. Panel 

Section 

...................................................................  47

7-2.  Front Panel Section .........................................................   48
7-3. Chassis 

Section 

...............................................................  49

7-4. Main 

Section 

...................................................................  50

7-5.  3 CD Mechanism Section (Australian model) 
 (CDM88A-K6BD90-WOD) 

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

51

7-6.  1 CD Mechanism Section (US and Canadian models) 
 (CDM77B-K6BD90-WOD) 

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

52

  ..............................   53

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.

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 viscou-s (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.

RELEASING  THE  DISC  TRAY  LOCK
The disc tray lock function for the antitheft of an demonstration 
disc in the store is equipped.

Releasing Procedure:
1. Press 

[

?/1

] button to turn the power on.

2.  Press the [FUNCTION] button to select CD function.
3.  While pressing the [

x

] button, press the [

Z

] button for more 5 

seconds).

4.  The message “UNLOCKED” is displayed and the disc tray is 

unlocked.

Note: When 

“

LOCKED

”

 is displayed, the slot lock is not released by 

turning power on/off with the

 [

?/1

]

 button.