HBD-DZ340, HBD-DZ340K, HBD-DZ640K, HBD-DZ740 - Sony Audio Service Manual (repair manual). Page 6

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.

How to open the disc table when power switch turns off 
Insert a tapering driver into the aperture of the unit bottom, and 
slide it in the direction of the arrow.

When installing a new OP unit, be sure to connect the fl exible 
printed circuit board fi rst of all before removing the static electric-
ity prevention solder bridge by unsoldering. 
Remove the static electricity prevention solder bridge by unsolder-
ing after the fl exible printed circuit board has already been con-
nected. 
(Do not remove nor unsolder the solder bridge as long as the OP 
unit is kept standalone.)

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.

On cleaning discs, disc/lens cleaners
•   Do not use cleaning discs or disc/lens cleaners (including wet 

or spray types). These may cause the apparatus to malfunction.

IMPORTANT  NOTICE
Caution: This system is capable of holding a still video image or on-
screen display image on your television screen indefi nitely. If you leave 
the still video image or on-screen display image displayed on your TV 
for an extended period of time you risk permanent damage to your tele-
vision screen.
Projection televisions are especially susceptible to this.

DISC  TRAY  LOCK
The disc tray lock function for the antitheft of an demonstration
disc in the store is equipped.
Setting Procedure :
1.  Press the [

?/1

] button to turn the set on.

2.  Press the [FUNCTION] button to set DVD/CD function.
3.  Insert a disc.
4.  Press the [

x

] button and the [

Z

] button simultaneously for fi ve 

seconds.

5.  The message “LOCKED” is displayed and the tray is locked.
Releasing Procedure :
1.  Press the [

x

] button and the [Z] button simultaneously for fi ve 

seconds again.

2.  The message “UNLOCKED” is displayed and the tray is un-

locked.

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

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

LASER DIODE  AND  FOCUS  SEARCH
1.  Open the case and turn POWER on with no disc inserted.
2. Confi rm that the following operation is performed while ob-

serving the objecting lens from the clearance of DVD mecha-
nism deck.
1)  Confi rm that laser beam is spread.
2)  Up and down motion of the objective lens. (2 times)