Fault 1
Amplifier not powering up.
Power input protection fuse checked no issue found.
Primary of the transformer checked and found to be open circuit.
Replacement Toroidal transformer fitted specifications 33-0-33 150VA.
As shown in the video R397 & R398 0.1 ohm 2 Watt resistors are in series with the speaker protection relay and the speaker terminals.
R398 was discoloured both resistors replaced to avoid a potential failure.
Bias for each channel set to 10 millivolts
Fault 2
No Audio output from the left channel irrespective of which input was selected.
Volume control potentiometer checked and found to be open circuit left gang.
Replacement 100KX2 D Shaft potentiometer fitted fixing the issue.
Due to the age of the Amplifier the speaker protection relay was also replaced to avoid any future issue of intermittent Audio loss at low volume or distortion.
All circuit boards checked for dry solder joints re-flowed as required.
User controls and switches cleaned with De-Oxit to ensure noise free operation.
Amplifier fully tested working correctly.
