PIONEER PL-640 (01) PDF MANUAL

The PL-S40 model comes in four versions distinguished by Type, Voltage, and Remarks as follows:

The PL-640 model comes in five versions distinguished by Type, Voltage, and Remarks as follows:

This service documentation is applicable to the PL-S40/KUT type.

Both model PL-S40 and PL-640 have the same basic mechanism and performance. The only difference is in appearance.

Information for servicing the PL-S40/KCT, R, WP, and PL-640/KU, R, WE, WB, WP types can be found in their respective sections dedicated to those models.

The power requirements are:

WE, WB, WP models: AC220 – 240V~, 50, 60Hz

KUT, KCT models: AC120V, 60Hz

R, R/G models: 110 – 120V/220 240V~ (switchable), 50, 60 Hz

Set this switch in accordance with the speed of the record which is to be played.

[33] (released position): For 33-1/3 rpm records.

[45] (depressed position): For 45 rpm records.

Use the switch for manual play.

Use the switch to suspend record play temporarily.

Use the switch when changing the tracks during actual play.

Depressed position: The tonearm rises (the stylus moves away from the record).

Released position: The tonearm descends (the stylus is lowered onto the record).

Press this switch to stop play.

This is rotated when performing the anti-skating adjustment.

This serves to hold and clamp the tonearm. When moving the tonearm, release the clamp.

This is used when adjusting the tracking force.

This is used when playing records without a “middle”.

A cartridge is not provided with the KUT and KCT models and so your own cartridge should be mounted, following the instructions laid down in CARTRIDGE MOUNTING.

1. Turn on the turntable and free the mechanism.

2. Fasten the tone arm to the arm rest.

3. Remove the rubber sheet and turntable.

4. Close the player hood and turn the player upside down and place it on a soft cloth so that the player hood is not damaged.

5. Remove the seven screws indicated as ①, and remove the under base.

6. Remove five screws indicated as ② and one screw indicated as ③.

7. Disconnect connectors A and B. The mechanism assembly can be removed from the panel.

8. Remove the three screws indicated as ④, and remove the motor.

Refer to the parts installation and assembly precautions section for more details.

1. Remove the mechanism assembly from the panel.

2. Using a soldering iron, disconnect the PU lead wires (arm lead wires) from the PU terminal board.

3. Remove the PU plate assembly AS spring.

4. Remove the one screw indicated as ⑤, and remove the PU plate assembly from the tone arm.

5. Remove the R clip.

6. Turn the player onto its side, remove the arm reset clamp, and remove the tone arm from the panel.

Remove the two screws indicated as ⑥.

The packing includes:

When ordering resistors, convert the resistance value into code form, and then rewrite the part no. as before.

The switch positions are:

OUTSIDE OF P.C. BOARD

S1 POWER: ON – OFF (The underlined indicates the switch position)

SPEED SELECTOR ASSEMBLY

S2 SPEED: 33 1/3 rpm – 45 rpm (The underlined indicates the switch position)

1. When the tone arm is moved toward the turntable, microswitch S1 (POWER switch) inside the mechanism section is turned on.

2. When S1 is turned on, 29V is applied to pin ⑦ of motor drive IC PA2008 (IC2) and the Hall element.

3. Since the PXM-126 is a slotless motor, the rotor (magnet) and drive coil positions are detected by two Hall elements, the current flowing in the drive coil is switched electronically, and the motor is rotated. When a voltage is applied to Hall elements HA and HB, a plus voltage (HA+) and a minus voltage (HA-) are generated by the magnetic field of the adjacent rotor. (Hall elements HA and HB are installed at positions at which their phases are electrically 90° apart.)

4. This voltage is applied to the position signal combination circuit of PA2008, and the waveform is shaped. The signals are further combined to produce a staircase signal.

5. This staircase signal is input to a four-phase drive circuit and the current flowing in drive coils LA and LB is switched alternately. Since this generates a magnetic field in the drive coils, the attraction or repulsion of the coil pole and rotor pole causes the motor to begin to rotate.

6. When the motor starts to rotate, the signal from the frequency generator (FG) at the motor rotating section is shaped and applied to pins of PA2007. The frequencies obtained are 55.55 Hz for 33 rpm and 75 Hz for 45 rpm.

7. This signal is amplified by the FG Amp of PA2007, converted to a voltage by the F-V converter, and applied to buffer amp 1.

8. On the other hand, a 6.144 MHz signal from a crystal oscillator is divided by the division circuit of PD1003. This signal is converted to phase comparison sampling pulses by a division ratio selection circuit and applied to a pin of PA2007.

9. The sampling pulses from PD1003 and the phase of the frequency corresponding to the motor speed are compared by the P-V converter of PA2007. The voltage corresponding to the phase difference is applied to buffer amp 2. The outputs of buffer amp 1 and 2 are combined and sent for comparison with the reference voltage to the absolute value amp of PA2008.

10. At the absolute value amp of PA2008, the input signal is compared with a reference voltage from PA2007, and the motor winding current is generated according to the voltage difference.

11. Since the speed does not reach the rated speed when the motor is started, the voltage is lower than the reference voltage. The absolute value amp gives a command which generates a positive torque to the rotating direction command circuit so the motor speed is raised. Then the motor gradually reaches constant speed. (When the motor speed is faster than the rated speed, since the voltage is higher than the reference voltage, the absolute value amp applies reverse braking torque to the rotating direction command circuit so the motor speed drops. Then the speed returns to the rated speed.)

1. Check the stylus landing position. If the stylus does not land at the correct position, adjust the landing position.

2. Set the arm elevation switch to UP and turn the auto-return adjustment screw fully counter-clockwise.

3. Move the tone arm as far as it will go toward the inside.

4. When the auto-return adjustment screw is turned slowly clockwise, the tone arm will begin to move toward the inside.

5. Stop turning the adjustment screw at the point at which there is a space of 32 mm between the cartridge stylus and the center shaft.

6. After adjustment, check that auto-return is performed correctly and that the stylus landing position is correct.

1. Depress the arm elevation switch to lower the arm.

2. Adjust the screw under the turntable so the stylus is 11 mm above the panel. When the adjustment screw is turned counterclockwise, the stylus rises.

3. Depress the arm elevation switch to raise the tone arm.

4. Adjust the screws next to the arm elevation switch so the stylus is 25.5 mm above the panel.

Place the record player on blocks as shown in the diagram and adjust the motor from the under base side.

1. Press the arm elevation switch and raise the tone arm.

2. The tone arm moves to the turntable side and the turntable rotates.

3. Set the turntable to 33 1/3 rpm.

4. Connect a buffer amplifier to pin ① of IC1 PA2007 of the motor circuit P.C. board unit as shown in the diagram and connect the output to an oscilloscope.

5. After the specified waveform appears on the oscilloscope, adjust the oscilloscope gain so the peak of the sawtooth waveform is at division 5. Then adjust VR1 (33 1/3 rpm) so that a:b = 2.7:2.3 as shown in the waveform diagram. (Be careful because noise enters easily.)

6. At the end of 33 1/3 rpm adjustment, adjust 45 rpm with VR2 as described in steps 2 and 3 above. Always adjust 33 1/3 rpm first. Always adjust 45 rpm even if only 33 1/3 rpm is incorrectly adjusted.

7. Connect an oscilloscope to pin ⑦ of PA2007 and check that the waveform is 55.5 Hz for 33 1/3 rpm and 75 Hz for 45 rpm.

Follow the directions and precautions when reassembling a unit after completing repairs. Be sure to lubricate as required, make no mistakes when attaching parts, and avoid all other careless mistakes that may be the cause of trouble later on.

Lubrication points are specified for oils other than GYA-008. Never use a different type of oil.

Apply grease to the heart-shaped grooved section (rear side of the cam) and lock plate sliding section in order to minimize wear on the sliding section and the burden on the mechanism.

Decrease the burden on the mechanism and the wear on the sliding section. Lubricate the sides, top, and bottom surfaces (sliding section of auto-stop mechanism) and the EV cam notched part (PU plate pin sliding section).

Apply oil to the raising shaft and sliding section of the bearing to assure stability in the elevation lowering speed. Apply all around at a width of 1mm on the half of the grooved section of the EV sheet assembly.

Coat the EV lever shaft section with grease so the EV lever operates smoothly.

Apply grease to the switch locker (opening) and sub-panel base sliding section to decrease the burden on the mechanism. When applying grease to the opening (shaft hole), do not apply any grease 2 ~ 3mm from the bottom surface. If grease is applied 2 ~ 3mm within the bottom surface, it may come out the bottom and go between the switch lever and sub-panel base causing the switch lever to operate ineffectively.

Coat the cut rod support section with grease so it operates smoothly.

As shown in the diagram, the reset plate SP hook is attached by putting the open section on the sub-panel base side.

The cam assembly is attached by letting the lock plate go in the direction A as shown in the diagram.

When attaching the arm base section to the mechanism section, put the mechanism section switch locker and switch lever in the locked position and verify that the tonearm is in the arm rest location. Also be sure to put the manual elevation lever in the up position and check that the PU plate shaft is in the position shown in the diagram.

The PU plate assembly is attached by pushing the PU plate bearing section against the arm rotating shaft fixing nut. The attachment direction is matched to the center of the support line as shown in the diagram (tone arm position on the arm rest).

When attaching the pushbutton switch to the EV lever, insert it at the groove at the bottom of the shaft as shown in the diagram. If it is inserted at the groove at the top of the shaft, arm elevation will not operate. Attach at the 2nd groove.

When attaching the mechanism assembly to the panel, be careful that the PU lead wire is not pinched at the panel boss as shown in the diagram.

When installing the PU lead wire and AC power cord, install them to the panel with string as shown in the diagram. After binding the cords, the cords must not contact the sub-panel. Clamp with the cord clamper.

Note: “-” indicates the part is not specific to this feature for that type or not applicable.

Note: “-” indicates the part is not specific to this feature for that type or not applicable.

Note: “-” indicates the part is not specific to this feature for that type or not applicable.

Measure leakage current to a known earth ground (water pipe, conduit, etc.) by connecting a leakage current tester such as Simpson Model 229-2 or equivalent between the earth ground and all exposed metal parts of the appliance (input/output terminals, screwheads, metal overlays, control shaft, etc.). Plug the AC line cord of the appliance directly into a 120V AC 60Hz outlet and turn the AC power switch on. Any current measured must not exceed 0.5mA.

For a 2-wire cord, also test with the plug reversed (using an AC adapter plug as required).

Any measurements not within the limits outlined above are indicative of a potential shock hazard and must be corrected before returning the appliance to the customer.

Many electrical and mechanical parts in the appliance have special safety related characteristics. These are often not evident from visual inspection nor the protection afforded by them necessarily can be obtained by using replacement components rated for voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in the provided documentation. Electrical components having such features are identified by marking with a ∆ on the schematics and on the parts list in the provided documentation.

The use of a substitute replacement component which does not have the same safety characteristics as the PIONEER recommended replacement one, shown in the parts list in the provided documentation, may create shock, fire, or other hazards.

Product Safety is continuously under review and new instructions are issued from time to time. For the latest information, always consult the current PIONEER documentation.