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Details on testing parameters and equipment for accurate measurements.
Physical dimensions, weight, and case finish information of the unit.
Input voltage, frequency, and power consumption details for operation.
Specifications for input/output levels, gains, and impedances.
Details on frequency response and group delay with filters engaged.
Various distortion tests and performance specifications.
Specifications for noise levels and channel crosstalk.
Dynamic range specifications for line and phono inputs.
Guidance on using adequate instrumentation for reliable testing.
List of recommended equipment for accurate measurements.
Procedures for calibrating and using test equipment effectively.
Explanation of the power supply design and voltage regulation.
Description of the mute relay and turn-on delay mechanism.
Detailed explanation of the phono input stage design and components.
How the phono input stage operates, including RIAA equalization.
Explanation of the infrasonic filter circuit and its function.
How external loops (tape, processor) are handled by the circuit.
Description of the unconventional volume control design.
Explanation of the mode control's function and operation.
Description of the balance control and its buffering.
Details on the tone control circuit and high frequency filter.
Description of the headphone amplifier circuit.
Advice on checking unit functions before disassembly.
Specific input/output tests for diagnostics.
How to use block diagrams to isolate problems effectively.
List of tools required for dismantling the unit.
Instructions for removing the bottom panel.
Instructions for removing the switchboard and jackboard.
Instructions for removing the top cover.
Instructions for removing the rear panel.
Instructions for removing the front panel.
Instructions for removing the sub front panel.
Instructions for removing the power supply and power switch.
General advice on troubleshooting methods and IC circuit diagnosis.
Precautions and initial power-up procedures before troubleshooting.
Expected voltages at test points for power supply verification.
Steps to diagnose and resolve hum problems, focusing on grounding.
Troubleshooting steps for the mute circuit and its relay.
Voltage checks and troubleshooting for the phono input stage.
Procedures for checking phono frequency response and impedance.
Troubleshooting noise issues specific to the phono stage.
Troubleshooting distortion issues in the phono stage.
Troubleshooting selector, tape, and external loop switches.
Troubleshooting for volume, mode, and balance controls.
Diagnosing hum problems related to the volume control.
Test points for volume and mode control circuits.
Referencing theory for mode control troubleshooting.
Troubleshooting tone controls and high frequency filter.
Procedure for fixing intermittent or faulty toggle switches.
Factors contributing to distortion in the tone control section.
Expected headphone amplifier gain and clipping levels.
Procedure for testing power, mute relay, and headphone output.
Testing clipping levels for various input signals.
Checks for external loops, switches, and signal integrity.
Procedure for checking high-level frequency response.
Testing RIAA equalization accuracy for phono inputs.
Testing tone, volume, and mode control operation and ranges.
Testing phono input impedance with capacitive loading.
Measuring distortion using a spectrum analyzer or distortion meter.
Procedures for measuring noise levels, including specific tests.
Information on obtaining the IHF Standard A-202.
Instructions for creating special input termination impedances.
Instructions for installing a pre-preamplifier.
Procedure for reducing preamp output level for system integration.
Instructions for connecting the unit to 240 Vac power.
Instructions for installing the rack-mount front panel.
Steps to remove the original front panel from the unit.
Steps to install the rack-mount front panel.
List of parts included in the rack-mount kit.
How to order replacement parts from Apt Corporation.
List of sheet metal and mechanical parts with part numbers.
List of hardware components like bolts and washers.
List of semiconductors (diodes, transistors, ICs) with part numbers.
List of passive components such as potentiometers.
List of switches, relays, and assemblies.
Details on building a voltmeter preamplifier for noise tests.
Description of a circuit for confirming RIAA response accuracy.
Instructions for creating special test cables and plugs for testing.
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