Refurbish C64 Power Supply Unit

This is a quick post regarding my Commodore64 Power Supply restoration. This C64 is my first computer and two days back its power supply get burn because of some short circuit in its output connector. This is a first time I open this C64 PSU and its internal circuitry is really simple to track down.

Commodore64 Power Supply Unit

Main component of this PSU is its 6 terminal step-down transformer. Other than that its circuit it limited to 2 rectifier diodes, 7805 positive voltage regulator, 2 - 1W resistors and 4700µF/16V electrolytic capacitor.
In my C64 PSU, defective component is 7805 voltage regulator, once I replace it and rewire the output terminal its starts to work again (like good old days).

Commodore64 Power Supply Schematic

Above diagram illustrate the schematic of my C64 PSU (which I was traced using original PCB). The high resolution images of PSU, are available at my flickr photo collection.

Comments

Power cords said…

Dilshan, Thanks for share this info with us I also faced short circuit problems your info is really helpful for all of us.

May 20, 2013 at 11:50 AM

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