Marantz PM4001 Amplifier Repair (With Audio Tutorial)

Fault
Amplifier not powering on.
Start-up circuit checked and IC96 MC7805 Regulator found to have failed.
Replacement LM7805 Positive 5 Volt installed fixing the issue.
C901,C901 & C903 100nF 50 Volt capacitors upgraded to 100 Volts as per the Marantz Service bulletin.
The capacitors are connected across the bridge rectifier on the main circuit board.
The modification prevents premature failure of the power transformer due to failure of the capacitors.
Bias for each channel checked and found to be at 5 millivolts as per factory setting.
Amplifier fully tested working correctly.