Arcam Delta 290 Amplifier Repair

Fault 1 Amplifier would not power up. FS501 Power input protection fuse open circuit T1.6A Q1,Q2 IRFP240 Power MOSFETS short circuit. Replacement MOSFETS restored normal operation to the left channel. Fault 2 Right Channel not working The Amplifier had previously been worked on and the power supply smoothing capacitors C201, C202 10000 uF had been replaced. The dual layer positive through hole connection for the +44V supply was damaged resulting in the loss of supply to R115 470 ohm resistor. PCB positive supply pad drilled and a link soldered through to restore correct operation. Output bias for both channels set to 4 millivolts. All user controls cleaned, Amplifier fully tested correct operation.