ANALOGUE AND DIGITAL SYSTEMS
V. Ryan © 2002 - 2009
Electrical signals are in
two forms; |
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This graph is typical of analogue signals. |
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Analogue signals:
These are usually older electronic gadgets (introduced before the mid
1990’s). A good example of an analogue signal is the loud-speaker of a
stereo system. When the volume is turned up the sound increases slowly
and constantly. |
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This graph is typical of digital signals |
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Digital signals: Modern electronic products such as computers and mobile phones depend on digital signals. However, a good example of a digital signal is Morse Code. The signal is sent as a series of ‘on’ and ‘off’ pulses. The signal is either present or it is not. Morse code was introduced in 1837 by Samuel Morse, as a method of communication.
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Both analogue and digital systems can be used as sensors. A thermistor is analogue as resistance slowly changes, a micro-switch is digital, as it is ‘on’ or ‘off’. Computers are digital devices and the various electronic parts communicate using 1’s and 0’s. 1 = ON0 = OFF |
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LIST EXAMPLES OF ANALOGUE SYSTEMS | LIST EXAMPLES OF DIGITAL SYSTEMS | |
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