Hi all. I am building a small spark erosion machine using a 50V DC x 5 amp power supply as the output source for the spark eroder. However, I do not need this "straight" DC. I need a circuit which can vary this 50VDC into a variable pulsed square wave. All help here will be appreciated ![Confused :confused: :confused:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)