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Repair Log… (10/4/11)


MPU4 – PSU Fault


Fault diagnosis.


Machine continually resets. Initial inspection.


Electro-caps are probably 20+ years old.

C2 is dented. The whole set-up looks grim.


Remove the fixing screws and remove the power supply pcb. There are 3 electro caps which need replacing,


C1 = 4700uF - 63VDC

C2 = 15000uF - 25VDC

C3 = 1000uF - 16V


If  you are unsure about polarity, check the psu schematic here and buzz out the cathode to the red connector.