Pioneer PL-55X User manual

STEREO
TURNTABLE
134-0>
<ART

. SPECIFICATIONS
.
PARTS
AND
THEIR
FUNCTIONS...
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.
OPERATION
OF
MOTOR
AND
MECHANISM
CONTENTS
3.1
RASEOR
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SEN
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5
3.2
Prior
to
Start
of
Playing
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3.3
Return
Operation...
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3.4
Stopping
Under
Manual
.......
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8
.
ADJUSTMENT
4.1
Tonearm
Will
Not
Return
to
The
Arm
Rest
.....
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9
4.2
Tonearm
Returns
to
The
Arm
Rest
Before
The
Record
Finishes
..........+..5:
9
4.3
Tonearm
Return
Speed
Is
Incorrect
20...
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9
4.4
Tonearm
Stops
before
It
Reaches
The
Arm
Rest
.....
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9
4.5
Tonearm
Hits
The
Inside
of
The
Arm
Rest.
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9
4.6
Tonearm
Bounds
in
The
Arm
Rest
.....
2.
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10
4.7
Arm
Elevator
Will
Not
Move
at
A
Correct
Speed
......
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10
48
Turntable
Will
Not
Turn
or
Stop...
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10
4.9
Adjustment
of
The
Shorting
Switch
Contacts
.......-
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10
4.10
Adjustment
Procedure
.......
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10
4.11.
Adjustment
of
Motor
Speed
and
Line
Voltage
Selector
f.0.4
5.2
eas
creed
ius
11
.
SCHEMATIC
DIAGRAMS
AND
P.C.
BOARD
PATTERN
5.1
Schematic
Diagrams
......
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5.2
Power
Supply
Circuit
Assembly
.
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.
EXPLODED
VIEW
6.1
COTteHtS
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SON
ROSE
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15
6.2
Main
Panel
.......
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17
6.3
Auto
Return
Assembly
(PXA-056)
6.
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18
6.4
Speed
Selector
Assembly
(KXA-766)
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tet
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tts
19
6.5
TOROAR
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6.6
Circuit
Board.
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WHE
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21
6.7
Anti-Skating
Assembly
(KXB-216)
6...
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tes
22
6.8
PU-Plate
Assembly
(PXA-065)
ow
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22
6.9
Power
Supply
Circuit
Assembly
(KWR-033)
6
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23
6.10
Start
Lever
Assembly
(KXA-761)
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23
6.11
Upper
Board
2.0...
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6.12
Under
Board
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25
6.13
Packing
Method
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26
6.14
Accessory
Case...
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27

1.
SPECIFICATIONS
Motor and Turntable
Motor:
Brushless
DC
servo
motor
Turntable
Drive:
_
Direct-driven
Speed:
Two
speeds,
33-1/3,
45
rpm
Wow
and
Flutter:
0.05%
(WRMS)
or
less
S/N:
58dB
or
more
(in
case
of
using
Pioneer
cartridge model
PC-50)
Turntable
Platter:
31cm
diam.
Aluminum-diecast
alloy
Tonearm
Tonearm
Type:
Static
balance,
S-shaped,
pipe
arm
Effective arm length: 221mm
Usable
Cartridge
Weight:
4g
(MIN)
to
14g
(MAX)
Overhang: 15.5mm
Subfunctions
Automatic
Return
Tonearm
System
Skating Force Canceler
Viscous-damped arm elevation
Plug-in
type
Light
Aluminum
Head
Shell
Dust
Cover
with
Free
Stop
Hinges
Wooden
Base
with
Anti-acoustic
Feed
back
Suspension
Strobolight
Accessories
Weight Plate (cartridge weight adjustable) 1
Cartridge
Mounting
Screws
10
Cartridge Mounting Nuts 2
Cartridge Mounting Washers 2
45 rpm Record Adaptor 1
Screwdriver 1
Sub weight 1
Overhang Gauge 1
Connection Cord 1
Operating Instructions 1
Miscellaneous
Power Requirements: AC 220V
50/60 Hz
Power Consumption: 5.2W (MAX)
Outer Dimensions: 480(W) x 410(D) x 185(H)mm
18-7/8(W) x 16-1/8(D) x
7-5/16(H) in.
Weight: 11.3 kg 24Ib 15 oz.
NOTE:
Specifications and the design subject to possible modifi-
cation without notice due to improvements.

2. PARTS AND THEIR FUNCTIONS
Stroboscope ———__—_--- —--
Refer to the accompanying illustration for positioning of
the strobo in respect to the line frequency and turntable
speed. On moving the function lever from OFF to ON/UP
and DOWN, strobolight is lit.
STROBOSCOPE
STROBOLIGHT
Cartridge Stylus Cover
Bring the cartridge stylus cover into position when the
PL-55X is not in use as shown in the accompanying
illustration.
45 rpm Record Adaptor
A 45 rpm record adaptor is supplied in the accessory
group, which permits 45 rpm EP records with large center
holes to be played.
Function Lever
At ON/UP
The turntable is driven. In moving this lever from DOWN
to this position, the tonearm (stylus) lifts slowly from the
record surface, thereby interrupting operation.
At DOWN
The tonearm is brought into position over the record.
_ Setting the lever to this position gently lowers the stylus
onto the record. Playing starts at this time.
At OFF
Moving the lever to this position from DOWN causes the
tonearm to lift and return to the arm rest. Power is cut off
and the turntable stops.
NOTES:
1. On moving the function lever from DOWN to OFF
pause at the ON/UP position until the am lifts from
the record. Failure to do so may allow the stylus to
bounce against the record and drag acrossit.
2. Also once you have moved the function lever to
DOWN you cannot immediately return it to OFF or
ON/UP.
3. Wait until the tonearm has floated dytwn on the
record and begun to play. Only the playing may be
interrupted.

— Arm Rest
The arm rest supports the tonearm. The tonearm should
always
sit
on
the
arm
rest
when
a
record
is
not
in
use.
Ordinarily,
the
arm
clamp
should
be
engaged
to
lock
the
tonearm in place on the rest.
ARM CLAMP
Fine Speed Adjustment Knob
With the turntable operating at 33-1/3 or 45 rpm, make
fine speed adjustment while observing the stroboscope.
Turning the knob in the (+) (clockwise) direction in-
creases speed while turning it in the (—) (counterclock-
wise) direction decreases speed. Marks on the turntable
must appear to “‘stand still’ under strobolight, indicated
correct speed.
2. 33-1/3 rpm
Ce 45 rpm
— 33-1/3 rpm Speed Switch
Push this switch if 33-1/3 rpm records are to be played.
— 45 rpm Speed Switch
Push this switch for 45 rpm operation.
ed 33-1/3 rpm
a 45 rpm
PL-55X
OPERATION
Operation of the PL-55X is uncomplicated. Use the
following procedure.
1. Place the record to be played on the turntable.
2. Move the cartridge stylus cover out of position.
Release the arm rest clamp.
3. Move the function lever from the OFF position
to the ON/UP position. At this time, the
turntable begins to turn.
4,Push the speed button (33-1/3 or 45 rpm)
corresponding to the speed of the record to be
played.
5. With the strobolight on, adjust the fine speed
control until the turntable appears to “stand
still’. Turning this control in the (+) direction
raises the speed, while turning it in the (—)
direction decreases the speed.
6. After the speed has been set to the proper value,
carefully move the tonearm into position over
the lead-in record grooves to be played.
7. Set the function lever to DOWN. The tonearm
drops gently to the record grooves and playing
begins.
8. To stop playing at an intermediate point, move
the function lever to the ON/UP position. If
operation is to be suspended, move the function
lever to the OFF position. (This action returns
the tonearm to the arm rest and stops the
turntable).
9. Upon completion of playing, the tonearm re-
turns automatically to the arm rest and the
turntable stops. The function lever returns auto-
matically to the OFF position.

3.
OPERATION
OF
MOTOR
3.1
MOTOR
Construction of motor control for the PL-35X is
depicted in Fig. 2.
1.
Applying power sets the oscillator into opera-
tion, Output of this circuit passes to the pole
position detecting circuit (L1 ~ L6).
. Here, assume that coupling between Lil and L4
is the tightest. Voltage induced in L+ is rectified
and applied to Q106/Q109 in the driver.
.Q109 in turn conducts and causes current to
flow in the associated drive coil (A-1). The rotor
moves in the direction shown by arrow in Fig. 1.
The magnetic pole affixed to the rotor induces a
voltage proportional to rotor movements, in the
sensing coil (A-4).
. Voltage induced in A-4 is rectified by a diode in
the speed sensor and applied to Q103 in the
control stage. This point is also fed from the
reference voltage generator (voltage Es) through
a fine speed control pot.
. Voltage applied to the base of Q103 in the
control stage controls current that flows in
Q104.
.Q104 serves as a constant current source for
Q106 through Q111 in the driver and therefore
controls current flow in the drive coils.
DETECTOR
AND MECHANISM
Pole Position Detector
Fig,
1
shows
a
simplified
view
of
the
drive
4
sense
cous.
With
power
applied
and
coupling
between
Ll
and
L4
high,
Q1LO9
causes
current
to
flow
through
A-l.
Asa
result,
the
rotor
end
of
coil
A-1
becomes
a
south
pole
($1)
and
attracts
N1.
The
rotor
moves
in
the
direction
shown
by
arrow.
Coupling
factor
between
L2
and
LS
increases
and
Operation
of
Q110
causes
current
to
flow
in
coil
A-2.
Pole
$2
attracts
pole
N2
and
rotor
rotation
continues.
In
the
same
manner,
$3
attracts
Pole
N3.
Continuation
of
this
process
causes
the
rotor
to
turn
on
a
steady
basis.
e and
ROTOR
DIRECTION OF
ROTATION
POLE POSITION
. When ambient temperature change causes driver DETECTOR Fig. 1
current to rise, the speed of rotation increases
above the rated value. Q104 current increases
and Q106 ~ Q111 currents decrease. As a result,
the speed of rotation falls off.
CONTROL STAGE
+8
33's9
O
Es O
ty” — a5
9 :
Qroz £
Qior
OSCILLATOR REFERENCE VOLTAGE
GENERATOR
Q ye
Ce | 09
cK) ce ia-1 G&S a-a
Ley Ss —H—
g Py Maen
Soe] (ESE |_|
«) .
la-3 M8 Sa- |
Qios
Ns
3
wa
6
wen
Qui a
= Fig. 2
POLE POSITION DRIVER DRIVE SENSING SPEED SENSOR
COILS COILS

3.2 PRIOR TO START OF PLAYING
1.
After
the
tonearm
has
been
swung
into
place
for
3.
Moving
the
FUNCTION
lever
to
the
DOWN
the
start
of
playing
of
the
record,
moving
the
position
turns
plate
(1)
still
further
through
link
FUNCTION
lever
to
the
ON/UP
position
causes
(1).
Pawl
(2)
engages
plastic
arm
(1).
plate (1) to turn through connecting link (1) to 4, The arm elevator riding on the cam portion of
the point at which pawl (1) engages plastic arm plate (2) drops, lowering the tonearm onto the
(1).
record.
2.
Plate
(2)
turns
along
with
plate
(1),
through
5.
Pawl
(3)
of
plate
(2)
applies
pressure
to
plastic
action
of
interconnecting
spring
(1).
Upon
com-
arm
(2),
so
that
there
is
no
interference
to
pletion
of
this
action,
the
microswitch
actuator
motion
of
the
stop
required
for
automatic
is
released,
thereby
applying
power
to
the
phono
return
operation.
motor.
The
turntable
begins
to
revolve.
PLASTIC
ARM(1) PLATE(1)
MICROSWITCH
ACTUATOR
LINK(1}
FUNCTION
LEVER
PIN OF PLASTIC ARM
PLASTIC ARM(2)
Fig. 3
No interference to
movement of plastic (
arm. anit
Cam action allows
tonearm to crop.
PLATE(2)
Fig. 4

3.3
RETURN
OPERATIONS
1.
When
the
tonearm
is
going
to
come
to
the
inside
(end)
of
the
record,
the
pick-up
lever
applies
pressure
to
the
aluminum
arm.
This
means
that
the
arm
is
coupled
indirectly
to
the
plastic
arm.
Resultant
action
causes
the
end
of
the
plastic
arm
to
swing
toward
the
center
of
the
turntable.
.
As
soon
as
the
tonearm
enters
the
return
groove
of
the
record,
the
pin
on
the
bottom
of
the
turntable
imparts
a
kick
to
the
plastic
arm.
_
Motion
of
the
plastic
arm
at
this
time
acts
on
plastic
arm
(1),
thereby
releasing
plate
(1).
Plastic
arm
(3)
then
locks
plastic
arm
(1).
This
action
closes
the
shorting
switch
so
that
noise
will
not
be
generated
as
the
tonearm
separates
from
the
record.
.
Plate
(1)
returns
through
action
of
spring
(2).
Plate
(2)
also
returns.
_
TURNTABLE SH
Playing
operation.
Return
operation.
PLASTIC
-
—
|
PIN
i
kg
Es
ALUMINUM
Plastic
arm
does
not
Plastic
arm
kicked
ARM
move
during
normal
when
tonearm
enters
play.
return
groove.
PLASTIC
ARM
PLASTIC ARM
PL-55X
_Return
of
plate
(1)
results
in
the
following
sequence.
Pressure
is
applied
to
plastic
arm
(1)
and
the
FUNCTION
lever
is
forced
back
to
the
OFF
position.
Action
of
link
(2)
returns
the
aluminum
arm
to
the
start
position.
.
Return
of
plate
(2)
results
in
the
following
sequence.
Action
at
the
cam
portion
of
plate
(2)
lifts
the
tonearm
from
the
record.
Plate
(3)
indirectly
coupled
to
plate
(2)
swings
the
tonearm
back
to
the
arm
rest.
Pressure
is
applied
to
the
microswitch
actuator,
opening
the
microswitch
contacts
and
stopping
the
phono
motor.
Pressure applied.
es
oe
PICK-UP
LEVER
Pick-up lever and
tonearm
directly
Fig.
5
connected
by
shaft.
Cam
action
lifts
tomearm
PLASTIC
while
motion
of
PL_ATE(3)
ARM
(1)
PLATE(3)
swings
tonearm
tack
to
the
arm
rest.
SHORTING
SWITCH
Pawl
disengaged
when
PLATE
(2)
plastic
arm
kicks
plastic
arm(1).
MICROSWITCH
Microswitch
ACTUATOR
Fig.
6

3.4
STOPPING
UNDER
MANUAL
1.
Moving
the
FUNCTION
lever
to
the
ON/UP
position
causes
pawl
(1)
of
plate
(1)
to
engage
plastic
arm
(1).
Phono
motor
operation
begins.
.
Moving
the
FUNCTION
lever
to
the
OFF
position
causes
plastic
link
(4)
to
shift,
in
turn
desengaging
pawl
(2)
from
plastic
arm
(1).
.
Action
of
spring
(2)
returns
plate
(1).
As
a
result,
the
phono
motor
stops,
as
described
under
(6)
and
(7)
on
page
7.
.
Moving
the
FUNCTION
lever
to
the
DOWN
position
initiates
playback
of
the
record.
When
this
lever
is
moved
from
the
DOWN
to
the
OFF
position,
pawl
(2)
is
disengaged
from
plastic
arm
(1)
through
action
of
plastic
link
(4).
The
phono
motor
stops,
as
described
under
(4)
through
(7)
on
page
7.
PLASTIC ARM(1)
DNs
PLASTIC LINK(4)
PaWilal ARM)
SHORTING
PNG
ee awit)
PLATE(1)
PLASTIC LINK(4)
Fig. 7

4. ADJUSTMENTS
4.1 TONEARM WILL NOT RETURN TO
THE ARM REST
If the pin at the back of the turntable is not (or
incorrectly) engaged with the plastic arm the
tonearm will not return to the arm rest. The
probable causes of the trouble are as follows;
(a) The tip of the plastic arm bends downward.
(b) The pin is bent.
(c) The pick-up lever is incorrectly mounted.
In case (a) or (b) is responsible for the trouble,
correct the curve of the plastic arm or the bend of
the pin. If necessary; replace the plastic arm as the
case may be.
In case (c) is the cause of the trouble, adjust the
screw provided at the tip of the pick-up lever so
that the pick-up lever will push the aluminum arm
when the head of the tonearm reaches the point of
130¢ from the center of the turntable (Fig. 8).
4.2 TONEARM RETURNS TO THE ARM
REST BEFORE THE RECORD FINISHES
The pick-up lever is incorrectly mounted. The best
solution to this trouble is to replace the plastic
arm.
This trouble also occurs when the plastic arm fails
to move smoothly. Oil the automatic return
mechanism.
4.3 TONEARM RETURN SPEED IS
INCORRECT
If the return speed is too slow, first insure that the
cause is not due to dirt.
Adjust spring (2) tension to give the correct spring,
increasing tension to increase speed and reducing
tension to decrease speed (Fig. 9).
m turn the nuts.
>
i:
SPRING(2}
Fig.
9
PL-55xX
4.4 TONEARM STOPS BEFORE IT
REACHES THE ARM REST
This trouble occurs when the plate (1) and the
plate (2) fail to move smoothly.
Oil
the
plate
(1)
and
plate
(2)
first
and
see
if
they
move smoothly.
If not, replace them.
4.5 TONEARM HITS THE INSIDE OF
THE ARM REST
See if the head of the tonearm rises 5 ~ 10mm off
the turntable with the FUNCTION lever set to
OFF. If the tonearm rises incorrectly, adjust the
height of the arm rest by means of the screw
provided on the arm rest base; if not, adjust the
height of the elevator rubber by means of the
adjust screw on the elevator arm shaft (Figs. 10,
11).
| UP AND DOWN
SCREW
ARM REST BASE
Fig. 10
Fig. 11