What is Oscilloscope?
[[File:CRT oscilloscope.png|right|thumb|300px|Illustration showing the interior of a cathode ray tube for use in an oscilloscope. Numbers in the picture indicate:<br /> <ol> <li>Deflection voltage electrodes</li> <li>Electron gun</li> <li>Electron beam</li> <li>Focusing coil</li> <li>Phosphor-coated inner side of the screen</li> </ol> ]] [[image:Tektronix Oscilloscope 475A.jpg|right|thumb|300px|A [[Tektronix]] model 475A portable analogue oscilloscope, typical of the late [[1970s]]. This dual-trace, dual-sweep instrument had a horizontal bandwidth of 250 [[Megahertz|MHz]], a maximum vertical sensitivity of 5 [[Volt|mV]] per division, and maximum (unmagnified) horizontal sweep speed of 10 [[nanosecond|ns]] per division. The vertical controls are on the left with Channel 1 above and Channel 2 below. The horizontal sweep controls are on the right with the Main Trigger above and the Delayed Trigger below. The [[Cathode ray tube|CRT]] controls are below the screen. The metal loop to the lower right of the screen provided a calibration signal for voltage and current [[Test probe|probes]].]] An '''oscilloscope''' (sometimes abbreviated '''CRO''', for [[cathode ray]] oscilloscope, or commonly just '''scope''' or '''O-scope''') is a piece of [[Electronics|electronic]] equipment that lets you see [[amplitude|changes]] or [[waveform]] in signal [[voltage]]. For example, if you want to see the signal a small electronic [[timer]] was producing, you could connect it to an oscilloscope and see. Usually, it shows a two-dimensional [[graph]] of one or more electrical [[potential difference]]s on the vertical axis. These graphs are plotted with time or some other voltage along horizontal axis. == Description == [[File:Oscilloscope diagram.png|left|222px|]] A typical oscilloscope is usually box shaped with a display screen, numerous input connectors, control knobs and buttons on the front panel. To aid [[measurement]], a grid called the ''graticule'' is drawn on the face of the screen. Each square in the graticule is known a