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Purpose of circuit description section for technicians.
Description of the amplifier section and its stages, including detailed circuit analysis.
Overview of tests and setup for performance verification.
Procedure to check idle power consumption of the unit.
Procedure to verify the delay timing of the output relay.
Procedure to check and adjust DC offset at the output terminals.
Procedure to measure the unit's hum and noise levels.
Procedure to test maximum power output at different loads.
Procedure to measure harmonic distortion.
Procedure to test output under short circuit conditions.
Procedure to measure frequency response across the audio spectrum.
Procedure to measure the amplifier's gain.
Procedure to compare gain between channels.
Procedure to measure the isolation between audio channels.
Instructions for safely disassembling the unit for service.
Procedure to adjust the bias current for optimal performance.
Procedure to adjust the DC balance for each channel.
Procedure to adjust for maximum power output.
Troubleshooting symptoms and causes for no primary power draw.
Troubleshooting symptoms and causes for excessive power draw.
Troubleshooting DC voltage issues at speaker terminals before relay activation.
Troubleshooting DC voltage issues at amplifier output terminals.
Troubleshooting symptoms and causes for lack of DC balance.
Troubleshooting symptoms and causes for parasitic oscillation.
Troubleshooting symptoms and causes for improper signal clipping.
Troubleshooting symptoms and causes for incorrect relay operation.
Troubleshooting symptoms and causes for no audio output.
Details changes for page 1 of the service manual.
Details changes for pages 2 and 3 of the service manual.
Details changes for page 4 of the service manual.
Details changes for page 5 of the service manual.
Details changes for page 6 of the service manual.
Details changes for page 9 of the service manual.
Details changes for page 10 of the service manual.
Details changes for pages 12 and 13 of the service manual.
Details changes for pages 14 and 15 of the service manual.
Details changes for page 16 of the service manual.
Details changes for pages 17, 18, and 19 of the service manual.
Details changes for pages 20 and 21 of the service manual.
Step-by-step guide to convert the unit to 220-volt operation.
Step-by-step guide to convert the unit to 100-volt operation.
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