Technics SL-P520 Compact Disc Player Service Manual
This document provides comprehensive technical information for the servicing and maintenance of the Technics SL-P520 Compact Disc Player.
Specifications
| Category | Details | Category | Details |
|---|---|---|---|
| Region Codes | |||
| (K) [M] | U.S.A. | (K) (S) [EG] | F.R. Germany. |
| (K) [MC] | Canada. | (K) (S) [EB] | Belgium. |
| (K) (S) [E] | Switzerland and Scandinavia. | (K) (S) [EH] | Holland. |
| (K) (S) [EK] | United Kingdom. | (K) (S) [EF] | France. |
| (K) (S) [XL] | Australia. | (K) (S) [Ei] | Italy. |
| (K) (S) [XA] | Asia, Latin America, Middle Near East, Africa and Oceania. | (K) (S) [PC] | European Audio Club. |
| (K) (S) [XB] | Saudi Arabia. | (K) (S) [PE] | European Military. |
| (K) (S) [PA] | East PX. | ||
| Audio | |||
| No. of channels | 2 (left and right stereo) | Low-pass filter | Hight Resolution Digital Filter |
| Frequency response | 4-20,000 Hz ±0.3 dB* | Output voltage | 2.0 V (at 0 dB)* |
| Dynamic range | 96 dB* | Output impedance | Approx. 600Ω |
| S/N ratio | 100 dB* | Load impedance | More than 10 kΩ |
| Harmonic distortion | 0.0015% (1 kHz, 0 dB)* | ||
| Total harmonic distortion | 0.003% (1 kHz, 0 dB)* | ||
| Channel separation | 100 dB | ||
| Wow and flutter | Below measurable limit* | ||
| Signal Format | |||
| Sampling frequency | 44.1 kHz | D-A conversion | 16-bit linear |
| Correction system | Technics Super Decoding Algorithm | ||
| Pickup | |||
| Type | Fine-focus, one beam | Light source | Semiconductor laser |
| Access time | 1 second* (access to the last track) | Wavelength | 780 nm |
| Traverse system | High-speed linear access system | Spindle system | Brushless DD motor |
| Infrared remote control unit | |||
| Dimensions (W×D×H) | 65×155×18 mm | Weight | 140 g (including batteries) |
| Batteries | UM-3 "AA" batteries or IEC R6 or equivalent (1.5V×2) | ||
| Headphones | |||
| Output level | 80 mW max. (variable) | Plug | 1/4 inch stereo |
| Impedance | 32 Ω | ||
| General | |||
| Power supply | For U.S.A. and Canada: AC 120V, 60 Hz For United Kingdom and Australia: AC 240V, 50 Hz For Continental Europe: AC 220V, 50 Hz For Others: AC 110~127V/220~240V, 50/60 Hz | Power consumption | 17 W |
| Dimensions (W×D×H) | 430×260×87 mm (16-15/16"×10-1/4"×3-13/32") | Weight | 4.3 kg (9.5 lbs.) |
| Color Options | |||
| (K) | Black Type | (S) | Silver Type |
Safety Precautions
This section details critical safety information for servicing the unit.
Laser Diode Precautions
Emphasizes the invisible nature of laser radiation and the need to avoid direct exposure to the beam. It includes specific caution labels and warnings like "DANGER-Invisible laser radiation when open. AVOID DIRECT EXPOSURE TO BEAM."
General Safety
Advises unplugging the power cord before servicing, using only manufacturer-recommended replacement parts, checking power cord condition, and restoring insulation barriers after servicing. An insulation resistance test procedure is also described to prevent electric shock hazards.
Handling Precautions for Optical Pickup
Highlights the sensitivity of the optical pickup to electrostatic discharge (ESD). It recommends specific handling procedures, including grounding measures and avoiding excessive shock or stress on the flexible board. It also warns against turning the variable resistor on the pickup.
Operation and Functions
This section describes how to operate the CD player and its various functions.
Playing a Disc
Provides step-by-step instructions for basic disc playback, including automatic play, inserting and ejecting discs, and using the play, pause, and stop functions. It also explains how the display panel indicates playback status.
Program Play
Details how to program a sequence of tracks for playback, including entering track numbers, confirming the program, and clearing entries. It also covers program confirmation using the recall button.
Random Access Play
Explains how to select specific tracks or index numbers for playback in any order.
Skip Play
Describes how to skip forward or backward to the next or previous track, including a quick skip mode.
Search Play
Details how to search for a specific point on a disc using the search dial or buttons, with options for high and low search speeds.
Remote Control Unit
Identifies all buttons on the remote control and their functions, such as numeric buttons, playback controls, program functions, and special features like Music Scan and A-B Repeat.
Disassembly and Internal Components
This manual provides detailed instructions for disassembling the unit and accessing its internal components.
Disassembly Instructions
Step-by-step procedures are given for removing the cabinet, front panel, operation PCB, headphones PCB, main PCB, disc clamper, loading base, disc holder, optical pickup, drive motor, and power transformer. Specific notes and cautions are included for each step, such as locking the disc holder mechanism during disassembly.
Printed Circuit Boards (PCBs)
Layouts and wiring connection diagrams are provided for the Operation PCB, Main PCB, Spindle Motor Drive PCB, Headphones Amp PCB, and Power Supply PCB. These diagrams illustrate the internal circuitry and component placement for different regional models.
Terminal Functions of LSI
Detailed tables list the pin assignments and functions for various Large Scale Integration (LSI) chips used in the system control, remote control signal processing, digital filter, and optical servo circuits.
Adjustment Procedures
This section outlines the necessary adjustments for optimal performance after servicing.
Electrical Adjustments
Procedures for electrical adjustments are described, including focus gain, tracking gain, tracking offset, best eye (PD balance), and PLL adjustment. These typically require an oscilloscope and specific test discs.
Mechanical Adjustments
Instructions for mechanical adjustments, such as turntable height and optical pickup alignment, are provided.
Troubleshooting Flowcharts
Diagnostic flowcharts guide technicians through checking various circuits (power, servo, digital/audio, CLV, loading motor) to identify faulty components.
Parts and Diagrams
The manual includes resources for identifying and replacing parts.
Replacement Parts List
A comprehensive list of replacement parts with part numbers and descriptions is available. It also includes diagrams of IC/diode terminals.
Exploded Views
Exploded views illustrate the physical assembly of the unit, showing the arrangement of remote control parts, cabinet and chassis parts, and loading unit components.
Schematic Diagrams
Detailed schematic diagrams provide a comprehensive overview of the unit's electrical circuitry, including signal paths and component interconnections.
Block Diagrams
Block diagrams visually represent the system architecture, showing the interaction between major functional units like the optical pickup, system control, digital processing, and audio output stages.
