The Oscilloscope

• An oscilloscope is a device that allows you to see how voltage changes over time by displaying a waveform of electronic signals
• The Oscilloscope consists of an electron tube, with associated control circuits, and X/Y - Plates.
• X-Plate controls the horizontal deflection of the beam on the screen.
• Y-Plate controls the vertical deflection of the beam on the screen.
• Electrons are directed through the tube, and displaced by the X/Y Plates, towards a fluorescent screen at the other end of the tube.
• The X-Plates are connected to the time base circuit, and deflect the electron beam left to right at a constant speed, (measured in milli or micro seconds/cm usually).
• The Y-plates are connected to the applied p.d that you seek to show, it they deflect the electron beam up/down with a calibration measured in V/cm
• The calibration of the Y-beam is called the Y-gain or Y-sensitivity
• To measure P.D, observe the amplitude of the projected wave, and multiply it by the Y-gain,: (a=1.6cm, Y-gain=5V/cm ... V=5*1.6=8V)