There are broadly two types of oscilloscope named as analogue oscilloscope and digital oscilloscope where the difference between both is well ill-starred by their name itself. Analogue oscilloscope involves only analogue signal during the processing of the signal in its various section like amplification, attenuation, filtration, deflection of any other operation some of its examples are sampling oscilloscope, conventional low frequency oscilloscope. But it is to mention here that it does not mean that it is not able to display digital signal as any wave of input signal can be studied by them irrespective of the types of oscilloscope used with some exceptions. On the other hand digital oscilloscope uses digital processing techniques in its various sections of processing like storage, transition between different sections. It is the availability of electronic circuits at relatively low cost that many digital features can be added to the analogue oscilloscopes like their storage. Some of the examples of such digital features involve a trigger after an elapse time or it may also be after a fixed number of pulses have passed. Digital display have some parameters like
• Integrated digital voltmeter
• Digital counter
• Remote control
In spite of the digital features embedded in it the basic system still remains an analogue oscilloscope on the basis of its working with some exceptions. Like an analogue oscilloscope CRT is used in it. The difference lies in the fact that it digitizes the analogue signal and as result all the substantial signals occur to be in digital form. As also has been told above that a conventional CRT is used here while storage of signal takes place in digital memory cells. The following figure 1.1 well describes the working of basic oscilloscope with the help of a block diagram. This is basically a complete digital oscilloscope. The signal that is encountered by the system generally occurs in analogue form which is first digitized at input section and then it is stored in memory in the same form. Being in digital form various types of analysis can be done upon it and many other type of information can be built with this system and this all is possible because of the digital form of the given signal because in digital form an information signal can be easily fed into a computer and analysed by conventional methods.