Service Mode - Sony Discman D-180AN Service Manual

Service Mode (service program)
The equipment is provided with a service program built in the mi-
crocomputer, like conventional models.
Service program operation methods are described in the following.
REPEAT/ENTER
Tracking gain-up mode while pressing
HOLD OFF n ON
Be sure to turn OFF the HOLD switch
(if ON, pressing each key is deactivated)
= (FR)
The optical pick-up
is moved inwardly
p (STOP)
All servos are turned OFF
+ (FF)
The optical pick-up
is moved outwardly
Fig. 3 Layout of each key
• Step 1 (Service mode setting method)
1. Turn OFF the HOLD switch the external power supply discon-
nected (power is not applied to the set).
2. Solder across the T802 (TEST) terminals (pin %™, IC801 (TEST)
is grounded).
3. Connect an external power supply.
Thus, the set is switched to the service mode.
• Step 2 (Operation in the service mode )
1. Once the service mode is effected, the LCD displays 5 indica-
tions each of which is repeatedly displayed.
However, the following operations can be activated even if LCD
indication is effected.
2. By pressing the + or = key, the optical pick-up movable
inwardly or outwardly. However, if this is activated, tracking
servo and sled servo are turned OFF, so it can be turned ON by
pressing the PLAY MODE key, if required.
3. By pressing the REPEAT/ENTER key, the tracking gain-up mode
becomes active.
4. By pressing the ^ key, focus is turned ON from focus search-
ing while entering CLV-S (pull-in mode).
Without disc, focus searching is repeated continuously.
5. By pressing the PLAY MODE key, tracking servo, sled servo
and CLV-A (servo in PLAY) are turned ON.
6. When 4. and 5. are performed, playing begins. No muting is ON
in the service mode.
7. By pressing the p key, all servos (focus tracking and sled) are
turned OFF. However, the disc motor revolves for a while by
inertia.
SECTION 4

SERVICE MODE

PLAY MODE
Tracking servo and sled
servo are turned ON
^ (PLAY/PAUSE)
FOCUS is turned ON
to effect pull in mode
• Step 3 (Resetting service mode )
1. Be sure to disconnect the external power supply and remove the
solder bridge at the TEST terminals connected in setting.
2. The set thus becomes available for normal operation.
– MAIN BOARD – (Side A)
Q302
IC301
Fig. 4 Location of test terminal
– 7 –
T802
(TEST)
T802 (TEST)
Normal mode : Open
Test mode : Short