Pioneer LD-700/KU User manual

(!,!) PIONEER
Service
cTWanual
CONTENTS
1. DISASSEMBLY 1-1
1.1 REMOVING THE EXTERNAL PARTS
AND CIRCUIT BOARDS 1-1
1.2 REMOVING THE PICKUP 1-1
2. MECHANISM ASSEMBLY AND
ADJUSTMENTS 2-1
2.1 PICKUP ASSEMBLY 2-7
2.2 PICKUP AND SLIDER ASSEMBLY 2-8
2.3 POSITIONING OF POTENTIOMETER
PINION GEAR 2-10
2.4 ADJUSTMENT OF CLAMP SWITCH . . .2-10
3. ELECTRICAL ADJUSTMENTS 3-1
4. SCHEMATIC DIAGRAM, PCB
PATTERN &PARTS LIST 4-1
4.1 OVERALL CONNECTION DIAGRAM. ... 4-1
4.2 LOCATION OF PCBs 4-3
4.3 FUSB, SFUB, RECB, DRVB, INTB,
CNNB &BLMB 4-5
4.4 PICKUP, PREB 4-9
4.5 LOLB, IRAB, DINB, KEYA, KEYB,
SRVB 1/3 (CONT) 4-13
4.6 SRVB 2/3 (FTS) 4-17
4.7 SRVB 3/3 (TBC) 4-21
4.8 DEMB 1/2 (VDEM) 4-25
4.9 DEMB 2/2 (ADEM) 4-29
4.10 REMOTE CONTROL UNIT (CU-700) ..4-33
4.11 PARTS LIST OF EACH PCBs 4-34
4.12 TR &ICs 4-39
4.13 WAVEFORMS 4-43
5. EXPLODED VIEW 5-1
5.1 EXTERNAL AND TOP VIEW 5-1
5.2 BOTTOM VIEW 5-4
5.3 MECHANISM 5-7
5.4 CU-700 5-10
5.5 PACKING MATERIAL 5-13
6. LABEL CHECK 6-1
7. SAFETY INFORMATION 7-1
8. SPECIFICATION 8-1
PIONEER ELECTRONIC CORPORATION *3-1,'Meguro 1-Chome, Meguro-ku, Tokyo 153. Japan
PIONEER ELECTRONICS (USA] INC. P.O. Box 1760. Long Beach. California SOBOI U.S.A.
TEL: [BOO] -421 -1 <304. [213] *320-531 *3
PIONEER ELECTRONIC (EUROPE] N.V. Keetberglaan 1. 27*30 Beveren, Belgium TEL: 03/775-2B0B
PIONEER ELECTRONICS AUSTRALIA PTY. LTD. 178-1B*3 Boundary Road. Braeside, Victoria 3135. Australia
TEL: [03] 5SO-3311

LD-7QO/KU
1. DISASSEMBLY
1.1 REMOVING THE EXTERNAL PARTS 1.2 REMOVING THE PICKUP
AND CIRCUIT BOARDS
Bottom cover
•Remove the 9screws (7)
•Remove the 2screws ©
|Bonnet
•Remove the 4screws (§)
•Remove the 6screws (4)
•Slide toward the back
to remove.
s
c
RVB, DEMB
rcuit boards
•Remove the 6screws (6)
|Slider |
•Remove the 2screws (8)
•Remove the 2 screws (§)
Pickup
Disc tray
•Turn the power on and depress
the REJECT button.
/•Or, after removing the SRVB \
and DEMB panel, adjust the \
position of the FL rack shown
in right figure. I
\•Release the latch. /
•Remove the 2screws (J)
|
Front panel
[
•Remove the 6screws (7)
Mechanism
chassis
•Remove the 3screws (f)
•Remove the Etype washer ®
•Remove the 4screws (l)
(2)
illustrated in (2).
1-1

<§ (2)
1-2
LO-700/KU

LD-7GO/KU
2. MECHANISM ASSEMBLY AND ADJUSTMENTS
2.1 PICKUP ASSEMBLY
Remove the backing and
attach the sheet.
2-1
2.2 PICKUP AND SLIDER ASSEMBLY
Assembly procedure:
1) Screw the tilt adjustment shaft into the pickup.
2) Place the pickup in the slider and attach the holder.
Note: Be careful not to apply pressure to the area
1around the objective lens or magnetic cir-
cuitry when doing this.
3) Attach the tilt adjustment shaft to the optical
body using the Etype washer.
4) Turn the slider upside down and attach limit gear.
Note: Be careful not to apply pressure to the area
around the objective lens or magnetic cir-
cuitry when doing this.
5) Rotate the worm gear until the pickup and
slider are parallel to each other (lines Aand B).
Aand B).
6) Attach the tilt motor and CTCB panel.
7) Properly route the wires around CTCB.
Attachment of limit gear B
Limit gear Bshaft
Attach limit gear C
with the U-shaped
section pointing
toward limit gear
Limit gear C
Attach so that there is no gap
between the pickup and
2-2
©

Tilt motor and CTCB panel attachment
2-3
©
LD-7QQ/KU
2.3 POSITIONING OF POTENTIOMETER PINION GEAR
•Adjust the projection of the pinion gear to •
the upper portion shown in the figure by idl-
ing the pinion gear when the pickup is
moved to the innermost position.
After positioning the pinion, turn the hexa-
gon socket setscrew clockwise until the end
of the screw lightly touches the potentiom-
eter holder. Then, turn back one full turn
and apply screw lock around the screw.
2.4 ADJUSTMENT OF CLAMP SWITCH
Adjustment should always
be done after replacing
the clamp switch.
1mm±0.5 mm
2-4
©

LD-700/KU
3. ELECTRICAL ADJUSTMENTS
Instruments and tools used:
•Color monitor TV
•Stereo system
•Dual trace oscilloscope (with time delay sweep,
DC-35MHz)
•Audio SG
•Frequency counter
•Shorting clips
•Test disc B1 (or FI
)
•CU-700
Precautions:
•Confirm that all power supply voltages are
correct.
©Confirm that there are no mechanical problems.
•Pinion adjustment of the slider potentiometer
must be completed.
•All parts of the pickup except the grating must
be correctly adjusted. Use FI test disc for the
grating adjustment.
•The oscilloscope range figures here assume the
use of a1:1 probe.
•Do not insert and remove discs when the player
is on its side up. (Do not press then /A button on
the player.)
Preparations:
•Connect amonitor TV and stereo amp to the
player.
•Remove the top and bottom panels.
•Insert atest disc.
•Perform PREB, SRVB and DEMB adjustments
with the player standing on its right side.
•Perform the PREB adjustment with the SRVB
and DEMB boards open (remove the SRVB and
DEMB board screws).
vr 1
VR 2
VR 3
VR4
VR 5
RF LEVEL
FOCS OFFSET
FOCS GAIN
TRKG BAL
TRKG GAIN
PREB adjustment points
TP 9
-11V
+1 ! V
GND
B1
B4
B2
B3
B1FB3
RF
FOCS A-
8
FOCS ERROR
TRKG GAIN MON.
TRKG OSC IN
+11 V
APC VCC
GNO
OSCILLOSCOPE TEST
POINT
ADJUST-
MENT
POINT
CHECK
POINT/
ADJUST-
MENT
STANDARD
ADJUSTMENT PROCEDURE
PREB ADJUSTMENT
On PREB
unless
otherwise
specified.
TP7
TP8
On PREB
unless
otherwise
specified.
0.25V -
0.5V
5mV/div
0.2V/div
O.lmS/div.
5mS/div
Positive
amplitude
=Negative
amplitude
Always perform the following adjustments after
replacing, repairing or adjusting the pickup or
replacing PREB.
CONFIRMATION OF THE LD POWER
•Measure the voltage between TP7 and TP8.
•Verify the voltage is in the range of 0.25V to 0.5V.
If not, replace the pickup.
FOCS OFFSET ADJUSTMENT
•Adjust the DC voltage of TP3 so that it is 0V±5mV
when the player is in the standby mode.
TRKG BALANCE ADJUSTMENT
•. Use search to locate frame #20,000.
•Open the TRKG loop. (Connect pins 20 and 22 of
SRVB Z401 PM4001 using the shorting clips.)
•Adjust so that the positive and negative sides of the
tracking error wave are equal.
3-2
©

LD-700/KU
NO.
OSCILLOSCOPE
VH
TEST
POINT
ADJUST-
MENT
POINT
CHECK
POINT/
ADJUST-
MENT
STANDARD
ADJUSTMENT PROCEDURE
TRKG LEVEL CHECK AND GRATING ADJUST-
MENT
X:
0.2V/div
Y:
0.2V/div
SRVB
TP-11
TP-12
Grating
Min. on X
axis
Max. on Y
axis
Max. on X
axis
MIN. on Y
axis
PRES
•Use testdisc Fj for grating adjustment.
•Use search to locate frame #15,000.
•Open the TRKG loop.
•Set the oscilloscope to the X-Y mode and observe
the tracking error (TP-1 1:X) and tracking A+B
(TP-12:Y) lissajous waveforms.
•Insert ascrewdriver in the PREB hole and slowly
rotate the grating until the amplitude of the lissajous
waveform is at its lowest point on the Xaxis and its
highest point on the Yaxis. The waveform should
also be smooth.
•Now rotate the screwdriver counterclockwise to
adjust the grating to the point where the amplitude
of the lissajous waveform is at its highest point on
the Xaxis and its lowest point on the Yaxis.
Note: If the lissajous waveform does not become
horizontal but remains slanted, the position
of the shaft holder may not be correct.
3-3
®

LD-7CJO/KU
NO.
OSCILLOSCOPE
VH
TEST
POINT
ADJUST-
MENT
POINT
CHECK
POINT/
ADJUST-
MENT
STANDARD
ADJUSTMENT PROCEDURE
RF LEVEL ADJUSTMENT
0.1 V/div ImS/div TP2 VR1 400mVp-p
•Close the TRKG loop.
•At about frame #18,000 adjust so that the TP2
output is 400mV p-p.
3-4

LD-700/KU
OSCILLOSCOPE
NO.
VH
TEST
POINT
ADJUST-
MENT
POINT
CHECK
POINT/
ADJUST-
MENT
STANDARD
ADJUSTMENT PROCEDURE
TRKG LOOP GAIN ADJUSTMENT
X:
0.5V/div
Y:
0.2V/div
X: TP6
Y: TP5 VR5
•Set the frequency of the FTG adjuster at 4kHz
(B1 disc) with Frequency-VR2. (3.7kHz: FI disc)
•Set the gain of the FTG adjuster at 4Vp-p with
Gain-VR2. Oscillator's output is available from
Yellow wire by turning the Switch to 2.
•Connect the Yellow wire of the FTG adjuster as
shown in the diagram.
•Connect red wire of the FTG adjuster as shown in
the diagram.
•Use search to locate frame #18,000.
»Adjust VR5 to turn J-LED on.
TRKG loop gain
(3.7kHz/4Vp-p: FI)
(4.0kHz/4Vp-p: B1)
REDWIRE YELLOWWIRE
3-5

LD-700/KU
OSCILLOSCOPE TEST
POINT
VH
X: X: TP4
0.2V/div Y: TP3
Y:
1V/div
ADJUST-
MENT
POINT
CHECK
POINT/
ADJUST-
MENT
STANDARD
ADJUSTMENT PROCEDURE
J-LED on
FOCS loop gain
BROWN WIRE
I
FOCS LOOP GAIN ADJUSTMENT
•Set frequency of the FTG adjuster at 1.8kHz (B1
disc) with Frequency-VRI. (2.1kHz: FI disc)
•Set the gain of the FTG adjuster at 1.2Vp-p with
Gain-VRI. Oscilator's output is available from
Orange wire by turning the Switch to 1.
•Connect the Orange wire of the FTG adjuster as
shown in the diagram.
•Connect the brown wire of the FTG adjuster as
shown in the diagram.
•Use search to locate frame #20,000.
•Adjust VR3 to turn on the green j(JUST) LED.
•Disconnect the FTG adjuster.
Oscilloscope
(2.1kHz/1.2Vp-p:
(1.8kHz/1.2Vp-p:
ORANGE WIRE
FI)
B1
)
3-6
®