Pioneer PL-5 User manual

Service
AL ETAIEY|
REPAIR
&
ADJUSTMENTS
ORDER
NO.
ART-705-0
STEREO TURNTABLE
L=-5
PL-420
MODEL PL-5 COMES IN FOUR VERSIONS DISTINGUISHED AS FOLLOWS:
Voltage Remarks
120V only U.S.A. model (Without cartridge)
120V only Canada model (Without cartridge)
110V—120V/220V—240V (Switchable) | General export model
110V—120V/220V —240V (Switchable) U.S. military model
MODEL PL-420(which is minor change in design from PL-5) COMES IN THREE VERSIONS
DISTINGUISHED AS FOLLOWS:
Voltage Remarks
120V only U.S.A. model
110V—120V/220V—240V (Switchable) General export model (Without dust cover)
110V—120V/220V—240V (Switchable) U.S. military model (Without dust cover)
= This is the service manual for model PL-5/KUT. For servicing of the other types,
please refer to the additional service manual.
= Ce manuel d’instruction se refére au mode de réglage, en francais.
= Este manual de servicio trata del método de ajuste escrito en espanol.
e For the circuit and mechanism descriptions, please refer to the supplement of model
PL-7 service manual (ART-768).
Ne ne at ees
PIONEER ELECTRONIC CORPORATION 4-1. Meguro 1-Chome, Meguro-ku, Tokyo 153, Japan
U.S. PIONEER ELECTRONICS CORPORATION 8&5 Oxford Drive, Moonachie, New Jersey 07074, U.S.A.
PIONEER ELECTRONIC (EUROPE?) N.V. Luithagen-Haven 9, 2030 Antwerp, Belgium
PIONEER ELECTRONICS AUSTRALIA PTY. LTD. 178-164 Boundary Road, Braeside, Victoria 3195, Australia
FU©®MAY 1981 Printicd in Japan
ag era

CONTENTS
1. SPECIFICATIONS .... 2.0.02. 022 eee eee 2
2. FRONT PANEL FACILITIES.............. 3
3. DISASSEMBLY ........ 200. e eee eee 4
4. TROUBLESHOOTING ..........- 202s 7
5. PRECAUTIONS FOR REASSEMBLY........ 14
6. P.C. BOARDS CONNECTION DIAGRAM..... 17
7. SCHEMATIC DIAGRAM .............0055 19
1. SPECIFICATIONS
Motor and Turntable
Drive System .....0.. 0.000 ccc cece eee eee eee Direct-drive
MOTOR sic ins tee cota Mt tee Salle tte sl del ah fangs) wha, LESS DC servo motor
Turntable Platter ......... 310mm diam. aluminum alloy die-cast
SPECS? ooe.ns Sesh evn ole wescbile dd vee wi scouts nace er ees 33-1/3 and 45rpm
Wow and Flutter ......... 0.00000 ee Less than 0.025% (WRMS)
Signal-to-Noise Ratio................ More than 78dB (DIN-B)
(with Pioneer cartridge model PC-3MC)
Tonearm
TEV DO: 5.220 yalens ccseiece steve oa Static-balance type, Straight pipe arm
Effective Arm Length. ........ 0.0000 e eee ee eee 221mm
Overhang.: cccies-os conse tnead whee ee ble wa ad eae 15.5mm
Usable Cartridge Weight..............-. 3g (min.) to 8g (max.)
Subfunctions
Full auto mechanism, Anti-skating force control, Stylus pressure
direct-readout counterweight, Cueing device, Strobe light, Free stop
hinges
8. BLOCK DIAGRAM...............0005. 21
9. ELECTRICAL PARTS LIST.............. 22
10. PACKING .. 0... cc eee es 23
11. EXPLODED VIEWS ...............0005 23
12. ADJUSTMENTS. ........ 0.00000 cee 29
REGLAGE Cae teAE Ghee dated ah 31
ASUST Ee seo ee Be ee ee es eit ae 33
Miscellaneous
Power Requirements... 2... 0. eee ee AC120V, 60Hz
Power Consumption .......... 0000 ee eee eee QW
Dimensions ............. 420(W) X 108(H) x 367(D)mm
16-1/2(W) X 4-1/4(H) X 14-7/16(D)in.
WIGHT 26 405 ee ew: BS ob Nee oo Be a GE SS 5.9kg/13 Ib
Accessories
EPL AGaDtel” ictese soe. ea Geta ee oats oh ole ee RA shee Bia Paes 1
Operating Instructions
NOTE:
Specifications and design subject to possible modification without
notice, due to improvements.

2. FRONT PANEL FACILITIES
@START/STOP switch
Depress this switch when starting auto play or when
stopping play.
(2) REPEAT switch
Set this switch for repeat play.
(3) DISC SIZE switch
Set this switch in accordance with the size of the record
which is to be played.
[7° 17] (released position):
[12’’ 30] (depressed position) :
(4) Speed check window
Look through this window and observe the movement
of the striped pattern when checking the rotational
speed or finely adjusting the speed. The position of the
striped pattern differs according to the power line
frequency (50 Hz or 60 Hz) in the area of use and the
speed (33 or 45 rpm) of the platter.
Top pattern: For 45 rpm in 50 Hz area
Second pattern: For 45 rpm in 60 Hz area
Third pattern: For 33 rpm in 50 Hz area
Bottom pattern: For 33 rpm in 60 Hz area
()SPEED ADJ control
Rotate this control in order to finely adjust the speed
of the platter.
The speed is reduced when the control is rotated in the
[~] direction.
The speed is increased when the control is rotated in
the [+] direction.
@® SPEED switch
Set this switch in accordance with the speed of the re-
cord which is to be played.
[33] (depressed position): For 33-1/3 rpm records
[45] (released position): For 45 rpm records
For 17 cm EPs
For 30 cm LPs
O8O®8
@ Cartridge
(8) Headshell
Q) Tonearm
40) ARM ELEVATION lever
Operate this lever when starting manual play or when
temporarily suspending play.
a) ANTI-SKATE control
This is rotated when performing the antiskating adjust-
ment.
(2 Arm rest
This serves to hold and clamp the tonearm. When
moving the tonearm, release the clamp
(13) Tracking force adjustment weight
This is used when adjusting the tracking force.
(4) Platter
(15) Platter mounting shaft
Rubber mat
47) EP adapter
This is used when playing records withouta ‘” middle.”’
(8) Cabinet
Dust cover

3. DISASSEMBLY
3.1 PANEL AND BASE
In removing the panel, follow the below listed
steps in the order given. Using any unnecessary
force will result in bending the springs or damaging
other parts.
Panel removal steps
1. Remove the headshell and weight assembly,
and the weight shaft assembly.
The weight shaft assembly is removed by
loosening screw (Hexagone socket screw) and
the headshell by loosening screw @.
2. Lift off the turntable platter.
Turntable platter
Panel
Dust cover
. Loosen insulator attachment screws @ and
remove the insulator. (Do not mix the color-
coded float springs. They must be replaced
with their original insulators during reassemb-
ly.)
. Set the record size selector switch to “‘30cm’’.
. Release the arm clamp and move the tonearm
as far as it will go toward the center. Then
rotate the motor center shaft clockwise return-
ning the tonearm to the arm rest. Stop the
center shaft.
. Remove the rear panel PU cord strain relief.
Weight assembly
Saen Rubber
52- Weight shaft assembly
\ Ground ‘wire
Control mechanism section
Fig. 3-1 Disassembly

7. Lift the front section of the panel (operating
controls) very slightly and make sure the slider
and spring is disengaged from the selector
lever. If the spring is caught on something,
use a long and thin screwdriver and free the
spring from the large center opening.
8. Unplug the 2P and 5P connectors.
9. Completely remove the PU cord from the panel.
10. Lift up the headshell end of the tonearm,
and taking care not to damage the tonearm,
remove it from the panel. (Hold the tonearm
steady.)
3.2 D.D MOTOR ASSEMBLY
After the panel has been removed, loosen the
three motor attachment screws @ and remove
the motor.
3.3 TONEARM SECTION
Remove the tonearm section by taking out the
three arm base attachment screws @ and one
ground wire securing screw @.
3.4 CONTROL MECHANISM SECTION
After
the
tonearm
section
has
been
removed,
loosen
the
three
control
mechanism
attachment
screws
@
and
remove
the
assembly.
Screwdriver
3.5 TONEARM
1. Disconnect the tonearm lead wires from the
PU board (See Fig. 3-2).
Note that some of the lead wires have been
soldered to the PU board, and must be discon-
nected with care.
2. Loosen the set screw @ with a screwdriver to
remove the PU plate under the arm base
(See Fig. 3-3).
3. Undo the screw @ securing the tonearm to the
arm base (See Fig. 3-3).
Tonearm
lead wires
Fig. 3-2 Disconnect the tonearm lead wires
PU plate
Fig. 3-3 Remove tonearm

Driver lever
spring
3.6 PANEL AND BASE REASSEMBLY
1. Turn the center shaft clockwise so that the
mechanism assembly is set to the reset posi-
tion.
Hook the driver lever spring to the panel boss.
Lift the forward of the panel and plug in the
2P and 5P connectors.
Clamp the tonearm in the arm rest and push
the START/STOP button.
Driver lever
Fig. 3-4 Spring positioning
. Attach the PU cord stopper.
. Attach the insulators. (Make certain the color-
coded float springs are attached to the correct
insulators.)
. Attach the weight shaft assembly.
Start Jever
Driver lever spring
Fig. 3-5 Positioning the spring

4. TROUBLESHOOTING
Use the following directions to find the cause of
each type of breakdown. Improper adjustment
units should be completely readjusted.
=# DOES NOT LEAD IN
Motor does not rotate.
YES
Arm clamp is not released.
m ”
Depression in EV rubber sheet.
YES
Tracking force is too heavy.
YES
Insufficient torque on the lead-in
latch. (See section 1)
YES
PU plate is not properly attached.
a
Oo Oo m
n
2
1)
oo | 2) m
vU m > =
Repeat switch is not ON.
YES
The start lever unit pin is separated
from the driving lever unit section.
(See section 2)
Control lever SP is weak.
Section 2
As shown in figure 4-2, if the start lever unit
Pin is out of line in the direction of @ , repeat will
not operate. If it is too far in the direction of ;
the unit will not start. In these cases, assemble
referring to the method of joining the panel and
bottom panel (lid).
NO Refer to the ‘‘Motor does not rotate”
section.
Section 1
As shown in figure 4-1, if the forre requirea
to turn over the lead-in latch is less tha 1 80g ata
point 13mm from the center, bend tke click leaf
spring toward until the force is 180 — 320g.
Lead-in—|3™.
latch
,,) Bend
“(180 — 3204)
Click leaf spring
EV cam
Fig. 4-1 Adjustment of lead-in latch with isu fficient
torque
Driving lever (B
® oA Pin
Driving leveispr- ing
Surface AX
a
Set
;
Control!
U
Start
lever
unit
base
Fig.
4-2
Misaligned
pin
of
start
lever
init

= REPEAT FUNCTION IS REPEATED
Separate the panel section and bottom panel
and, as shown in figure 4-3, apply a tension of
10g to the start lever unit pin in direction(A) If
the repeat function operates, the selector and reset
plate sections are not moving properly. If the unit
stops, the driving lever (B) is not moving properly.
Driving lever (B) is not moving pro- NO
perly.
YES
Start lever is not moving properly. NO
YES
Selector is not moving properly. NO
(See section 3)
YES
Reset plate is not moving properly. NO
(See section 4)
YES
Reset plate SP is weak.
Section 3
If
there
are
protrusions
remaining
from
the
original-pressing
process
on
surfaces
@),®),
and
©of
the
sub-panel
which
slides
with
the
selector,
the
movement
of
the
selector
will
be
adversely
affected.
Therefore,
these
protrusions
must
be
removed
(Fig.
4-4).
Section
4
If there are plastic protrusions on the pressure
pin section of section (D) of the reset plate, these
protrusions will come in contact with the lower
surface of the driving panel when the reset plate
moves in direction (E) and the movement of the
reset plate will be adversely affected. Therefore,
these
protrusions
must
be
removed
(Fig.
4-4).
= AUTO-RETURN DOES NOT WORK
Section 5
After performing the return operation, if the
curved section of the signal plate and curved sect-
ion of the starting plate are not in contact with
surfaces ‘A) and (B) respectively of the cam, reset
will be incomplete and the starting position will
be late. As a result, the return function may not
operate at times. In this case, bend the signal
plate (C)so that dimension A is 0.5mm or larger.
4)
Sub-panel
Start
lever unit
Fig. 4-3 Check of repeat operation.
Driving lever (B) shaft is bent.
Start lever is warped.
Plastic protrusions on cut surfaces of
the sub-panel of the selector slide
section.
Protrusions on reset plate pressure
pin.
® Sub-panel
(2e>
m SON
@® Lv
\C MINS Reset plate SP
20
. So Reset
o= plate
Fig. 4-4 Improper movement of selector
Signal plate
Starting plate
TOO least 0.5mm
Cam
Fig. 4-5 Incomplete reset of starting and signal plates

Change in starting position adjust-
ment.
YES
Starting plate does not follow the NO Too much grease between the signal
signal plate. plate and the cam.
YES
Inner diameter of the starting plate
hole is small.
Protrusions on the caulk section of
the starting plate hole.
Not enough grease between the
starting plate and signal plate.
i
After starting, incomplete reset of the NO The curved section of the signal
signal plate. (See section 5) plate is deformed.
YES
The inner areas of records can not 7 ;
be-tracked. Arm lead wire is caught on something.
YES
PU cord is touching the PU plate.
Operator of the detection lever is
not smooth.
i
Looseness in the PU plate attach-
ment.
= RETURN IS FAST (RETURN AT 1mm PITCH)
Protrusions on the pinion gear section
(See section 6)
Section 6
If there are rough areas of plastic protruding
from the (A) section of the protruding section of
the pinion gear, the return function may operate
at a pitch of only 1mm. In this case, remove the Fig. 4-6 Elimination of pinion
plastic
protrusions
completely
(Fig.
4-6).
gear
protrusions
Pinion geai
Protruding
section

= TONEARM DOES NOT LOWER IN CORRECT POSITION
Incorrect adjustment.
YES
PU plate operation is not smooth.
PU lever A and PU lever B are not
moving smoothly.
Location of stylus was changed
during cartridge replacement.
= RECORD SIZE SELECTOR DOES NOT WORK
Tonearm descends at 17cm location when
record size selector is set at 30cm.
Size select SP is warped.
YES
Size select lever does not operate Size select lever is warped
smoothly. :
Tonearm descends at 30cm location when record
size selector is set at 17cm.
Size select return SP is warped.
YES
Plastic protrusions in auto-stop
mechanism resin section of the select
lever sliding surface.
Select lever does not operate smooth-
ly.
Plastic protrusions on the select lever.
Index cam does not operate smoothly. = Sapte ped sheoked Secnen
YES
Size select SP is weak. |
# MOTOR DOES NOT ROTATE
2P or 5P connectors are not at-
tached.
YES
Connector(s) is not properly installed.
10