The function of the electronic parts in these systems is to receive input information, to process this information and then to produce an output. For example, in a computer, the input information is provided by pressing the buttons on a keyboard, the processing may involve arithmetic or comparison with previous information in a memory and the output will be a print out or a display on a video display unit. In another example, both input and output of a communications system may be sound such as words or music.
In other areas such as instrumentation and control, these are many non-electronic systems widely used. Both power steering and servo assisted brakes in automobiles are usually non-electronic and mechanical clocks and watches still have a share of the market.
Electronic systems are required to process or react to information. The information may have many forms, including physical quantities such as temperatures, velocity or mass, simple on/off information resulting from a switch being operated, or the highly concentrated and detailed information in speech, music and pictures. All these different forms of information have one common factor i.e. both amplitude and frequency may vary with time. ...Show more