Electrical Adjustments - Sony D-E707 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 (service program) "
on page 9.
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: DC2.5 V in battery termi-
nal
VOLUME knob : Minimum
RESUME switch : OFF
ESP switch : OFF
AVLS switch : NORMAL
HOLD switch : OFF
Before Beginning Adjustment
Set the equipment to service mode (See page 9) and check the
following. If there is an error, repair the equipment.
• Checking of the sled motor
1. Open the upper panel.
2. Press the + and = keys and check that the optical pick-
up can move smoothly without sluggishness or abnormal noise
in innermost periphery n outermost periphery n innermost
periphery
+ : The optical pick-up moves outwardly.
=: The optical pick-up moves inwardly.
• Checking of focus searching
1. Open the upper panel.
2. Press the ^ key. (Focus searching operation is activated
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.
VCC Adjustment
Adjustment Procedure:
MAIN board
TP401 (VCC)
SUFFIX-11: See page 12
SUFFIX-12: See page 13
1. Set the equipment to service mode stop state. (See page 9)
2. Connect the digital voltmeter to TP401 (VCC) on the MAIN
board.
3. Adjust RV401 on the MAIN board so that the reading on digi-
tal voltmeter goes 2.53 V.
Specifications: 2.5 V to 2.55 V
4. After the completion of adjustment, reset service mode. (See
page 9)
Adjustment Location: MAIN Board (SUFFIX-11: See page12,
SUFFIX-12: See page 13)
SECTION 5

ELECTRICAL ADJUSTMENTS

Focus bias Check
Condition:
• Hold the set in horizontal state.
Check Procedure:
1. Set the equipment to service mode stop state. (See page 9)
2. Connect the oscilloscope to the test point TP522 (RFO) on the
3. Move the optical pick-up to the center by pressing the +
4. Put the disc. (YEDS-18)
5. Press the ^ key.
6. Press the PLAY MODE key. (Both tracking and sled are turned
7. Check the oscilloscope waveform is as shown below.
RF Signal Reference Waveform (Eye Pattern)
digital voltmeter
(DC range)
8. Stop revolving of the disc motor by pressing the p key.
9. After the completion of adjustment, reset service mode. (See
+
–
Checking Location: MAIN Board (SUFFIX-11: See page12,
– 10 –
MAIN board
TP522 (RFO)
TP520 (VC)
SUFFIX-11: See page 12
SUFFIX-12: See page 13
MAIN board.
and = keys.
From focus searching, focus is turned ON while entering
CLV drawing-in mode. Tracking and sled are turned OFF.
ON)
A good eye pattern means that the diamond shape (≈) in the
center of the waveform can be clearly distinguished.
VOLT/DIV : 200 mV (With the 10:1 probe in use)
TIME/DIV : 500 ns
To watch the eye pattern, set the oscilloscope to AC range and
increase the vertical sensitivity of the oscilloscope for easy watch-
ing.
page 9)
SUFFIX-12: See page 13)
oscilloscope
(AC range)
2 k Ω
+
–
RF level
0.8 to 1.2 Vp-p