Electrical Adjustments - Sony D-V7000 Service Manual

Precautions for Adjustment
1. Before beginning adjustment, set the equipment to service
mode.
After the completion of adjustment, be sure to reset the ser-
vice mode.
For more information, see "Service Mode (Test Mode)" on
page 7.
2. Perform adjustments in the order given.
3. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise
indicated.
4. Power supply voltage requirement: DC6 V
HOLD switch : OFF
VOLUME control : Minimum
RESUME switch : OFF
Before Beginning Adjustment
Set the equipment to service mode (See page 7) and check the
following. If there is an error, repair the equipment.
• Checking of the sled motor
1. Open the upper lid.
2. Press the ^ key once.
3. Press the + and = keys and check that the optical pick-
up can move smoothly without sluggishness or abnormal noise
in innermost periphery → outermost periphery → innermost
periphery.
+ : The optical pick-up moves outwardly.
= : The optical pick-up moves inwardly.
• Checking of focus searching
1. Open the upper lid.
2. Press the ^ key thrice. (Focus searching operation is acti-
vated continuously.)
3. Check the object lens of the optical pick-up for smooth up/
down motion without sluggishness or abnormal noise.
4. Press the p key.
Check that focus searching operation is deactivated. If not,
again press the p key slightly longer.
SECTION 5

ELECTRICAL ADJUSTMENTS

– 8 –
Tracking Balance Check
Condition:
• Hold the set in horizontal state.
Connection:
MAIN board
TP524 (TE)
TP534 (VC)
(see page 10)
Checking Method:
1. Connect the oscilloscope to TP524 (TE) and TP534 (VC)
on the MAIN board.
2. Set the equipment to service mode stop state. (See page 7)
3. Move the optical pick-up to the center by pressing the +
and = keys.
4. Put the disc (YEDS-18).
5. Press the ^ key.
From focus searching, focus is turned ON while en-
tering CLV drawing-in mode. Tracking and sled are
turned OFF.
6. Confirm that a waveform on the oscilloscope is vertically
symmetric against 0 V.
0 V
A=B
7. Stop removing of the disc motor by pressing the p key.
8. After the completion of check, reset service mode. (See
page 7)
Connection Location: MAIN board (See page 10)
oscilloscope
(DC range)
10 k Ω
+
2200 pF
–
Note: Take long sweep time
for easy monitoring.
A
0.7 – 1.1 Vp-p 0 V
B
A=B
A
B