Before looking at the detailed traces, let’s understand the high-level flow of the circuit.
A specialized system protection circuit manages potential hazards, including:
| Symptom | Likely Fault Area | |-----------------------|---------------------------------------------| | Blows mains fuse | Short output transistors, bad rectifier diode | | One channel dead | Open emitter resistor, broken driver transistor, cracked solder joint | | Distorted audio | Low bias voltage, dried-up caps in preamp power | | Thermal protection triggers early | Thermal paste dried, mis-biased output stage | | No power, relay clicks | ±15V missing (blown 7815/7915) |
Components & Parts