Courses: P4, P14
Capacitor charge and discharge curve displayed on scope.
Connect a 5 or 6V power supply in series with a resistor box and capacitor box. A two-way switch is wired such that when pressed the power supply is in the circuit, and when released the circuit shorts, bypassing the power supply. Measure across the capacitor. I've been using the HP 54600 scopes for this demo, which seem easier to set up and use than the newer Rigol scope.
Scope setup: set the vertical access zero point near the bottom of the display, and the horizontal axis zero near the left side of the display. Horizontal axis 500 ms/div, vertical axis 1V/div. Trigger is set to rising slope, and to just above zero. Press Erase, then Auto-store, then press and hold the switch down. Once the trace reaches the top, release the switch to display the discharge curve. Change the resistance or capacitance and press Auto-store without pressing Erase first, and again press and release the switch to show the new curve superimposed on the first curve.
