Denon DP-60L - Service Manual

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N
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Hi
Fi
Component/Record
Player
SERVICE MANUAL
SERVO-CONTROLLED
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DIRECT
DRIVE
RECORD
PLAYER
MODEL DP-60L
Model DP-60L
NIPPON COLUMBIA CoO, LTD.

Summary

Features of the DP-60 L Turntable

Low Mass Tonearm for Improved Fidelity

Magnetic Recording Speed Detection System

Auto-Lift with Non-Contact Record-End Sensor

Lifts tonearm and stops platter at record end, preventing stylus wear.

PLL Servo Control with Quartz Oscillator

Guarantees speed accuracy below 0.002%, immune to environmental factors.

Names of Parts and Function

Power Switch Operation

Controls power on/off and illuminates indicator lamps.

Start Button Functions

Stop Button Operation

Lifter Button Control

Counterweight for Tracking Force

Anti-skating Knob Adjustment

Adjustment Procedures

Detection Head to Platter Spacing

Adjust spacing to approximately 0.15 mm for proper stop condition.

Regulator Voltage Confirmation

RPM Speed Adjustment

Adjust VR2 and VR1 for 45 and 33 RPM using oscilloscope waveforms.

Arm Lifter Height Adjustment

Set 0.5~1.0 mm clearance between arm lifter and arm tube.

End Adjustment (Lead-out)

Adjust lead-out indicator by positioning stylus at 53 mm from motor shaft.

Changing Operational Voltages

Multi-voltage Model Voltage Selector

Adjust voltage selector switch to match local line voltage for multi-voltage models.

Non-accessible Voltage Selector Models

Semiconductor Lead Connections

Exploded View of Tonearm

Circuit Diagram

Printed Circuit Board Layouts

Exploded View of Main Parts

Main Specifications

Phono Motor Specifications

Tonearm Specifications

General Specifications

Overview

1. Function Description
2. Usage Features
3. Maintenance Features

The Denon DP-60L is a high-fidelity, servo-controlled direct drive record player designed to deliver exceptional audio reproduction and user convenience. This turntable integrates advanced technology and thoughtful design to enhance the listening experience while minimizing common record playback issues.

Function Description

At its core, the DP-60L is a record player that spins vinyl records at precise speeds (33-1/3 and 45 rpm) to allow a cartridge and stylus to extract audio information from the grooves. Its direct drive system, coupled with servo control, ensures stable and accurate platter rotation.

A key feature is the servo-controlled direct drive system, which utilizes Denon's magnetic recording speed detection. This system detects the platter speed with high frequency (1000 pulses per rotation), enabling ultra-fast response of the servo loop. This effectively eliminates overshoot, wow, and flutter, contributing to a stable and accurate playback speed. Further enhancing speed accuracy is the PLL servo control via a quartz crystal oscillator, which guarantees exceptional speed stability, making the turntable almost totally immune to variations in temperature, humidity, load conditions, or supply voltage fluctuations.

The turntable incorporates a bi-directional servo control and electronic braking system. This combination, along with rotational detection, provides quick, smooth starts, stops, and speed change-overs, enhancing both convenience and the longevity of your records.

The tonearm is a crucial component, designed for optimal trackability and fidelity. It features a low-mass design, with the head shell integrated into the arm tube and a connector at the base. The materials used for the tonearm are carefully selected to minimize effective mass, ensuring that even with high-compliance cartridges, the low-end resonance frequency remains optimal. This design contributes to clearer sound by mitigating the effects of record warpage and rotational eccentricity, as well as intermodulation distortion. The straight-shaped tonearm's symmetrical design improves dimensional and mechanical accuracy, reducing tortional distortion and enabling higher fidelity reproduction.

A significant convenience feature is the auto-lift mechanism with a non-contact record-end sensor. When a record playback is complete, the tonearm is automatically lifted from the record, and the platter rotation stops. This prevents unnecessary stylus wear from tracking the lead-out grooves. The non-contact sensor detects the tonearm's velocity change using an opto-electronic transducer, ensuring no additional load on the record or stylus, thus leaving sound quality unaffected. The arm lifting device itself employs a servo-controlled angular control motor, developed by Denon, for ultra-smooth and silent up and down motion.

Usage Features

The DP-60L is designed for straightforward operation with several user-friendly controls.

• Power Switch: Pressing the switch turns the unit on, illuminating lamps in the stop button and strobe viewing window. Pressing it again turns the power off. If the arm lifter is down when power is turned on, it will automatically lift.
• Start Buttons (33 and 45 rpm): Dedicated buttons allow you to select the desired playback speed. Pressing one illuminates its lamp and starts platter rotation, while simultaneously lowering the arm lifter.
• Stop Button: Pressing this button lifts the arm lifter, and after a brief delay, the "33" or "45" lamp turns off, and the platter stops. The delay ensures the stylus clears the record before rotation ceases.
• Strobe Viewing Window: This window allows you to observe the strobe pattern on the platter. When the platter is rotating at the specified speed, the pattern should appear stationary, confirming accurate speed.
• Lifter Button: This button allows manual control of the arm lifter, moving it up or down with each press.
• Cueing Lamp: This lamp illuminates when the arm lifter is in the down position.
• Counterweight: This weight is used to adjust the tracking force of the tonearm.
• Anti-skating Knob: This knob applies an outward force to the stylus tip, counteracting the inward skating force that occurs during playback.
• Replaceable S-shaped arm tube: The low-mass straight arm tube can be replaced with an S-shaped arm tube using a standard 4P connector. This versatility allows users to utilize a wider range of head shells or integrated cartridges, broadening cartridge selection and enhancing audio enjoyment.

The turntable also offers voltage selection for different regions. For multi-voltage models, a voltage selector switch is located on the base surface, allowing users to adjust the operational voltage to match their local line voltage using a screwdriver. This ensures compatibility and proper operation across various power grids.

Maintenance Features

The DP-60L is designed with maintainability in mind, offering specific adjustments and considerations for optimal performance and longevity.

• Adjustment of Spacing between Detection Head and Platter: This critical adjustment ensures proper operation of the magnetic recording speed detection system. The spacing should be approximately 0.15 mm between the magnet-coated platter surface and the detection head. Correct adjustment ensures proper stopping behavior of the platter. If the magnetic head is replaced, careful attention to terminal connection is required to prevent reverse platter rotation.
• Confirming Regulator Voltage: The power source uses a fixed voltage 3-terminal IC, and its output voltage (5V±0.2V) should be confirmed. No adjustment is typically needed for this component.
• RPM Adjustment: The turntable's speed (33 and 45 rpm) can be precisely adjusted using internal potentiometers (VR1 and VR2) while observing the waveform on an oscilloscope. This allows for fine-tuning of the pulse position within the square wave cycle, ensuring accurate playback speeds.
• Arm Lifter Height Adjustment: While factory-set, the arm lifter height can be re-adjusted if necessary. This involves loosening screws, lowering the arm lifter, placing the stylus on the record, and then adjusting the clearance between the arm lifter and arm tube to be 0.5-1.0 mm before tightening the screws.
• End Adjustment (Lead-out Adjustment): This adjustment, primarily for the straight arm tube, ensures the auto-lift mechanism functions correctly at the end of a record. It involves setting the anti-skating knob to '0', confirming the cueing lamp is off, positioning the stylus at 53 mm from the motor shaft using an overhang gauge, and then turning a lead-out adjusting screw until the lead-out indicator lights. This ensures the arm lifts at the correct point.
• Offset Adjustment: If the IC1 (KU-356) on the arm servo P.C. board is replaced, an offset adjustment is required. This involves short-circuiting specific points on the P.C. board and adjusting VR1 to achieve a specific DC voltage at a designated terminal of IC1.
• Tonearm Lifter Lubrication: For smooth operation of the automatic arm lift, a special silicone grease (SILICONE GREASE G-31) is applied to the lifter shaft/cylinder bearing. During servicing, it's recommended to clean the shaft and cylinder and re-apply this grease. After reassembly, the lifter shaft should move smoothly up and down and fall by its own weight, indicating proper lubrication.
• Parts List and Circuit Diagrams: The service manual provides comprehensive parts lists for various units (motor servo amp, arm servo amp, switch unit, fuse units, power units) and detailed circuit diagrams. These resources are invaluable for troubleshooting, component replacement, and understanding the internal workings of the turntable.
• Exploded Views: Exploded diagrams of the tonearm and main parts are included, offering a visual guide for disassembly and reassembly, which is crucial for maintenance and repair tasks.
• Safety Warnings: Shaded parts in the parts lists are identified as important for safety. Users are advised to always replace these parts with the same type and rating to maintain safety standards.

Denon DP-60L Specifications