Category: 6. Input/Output Devices

Sound Transducers use electrical energy to create mechanical vibrations to disturbe the sourrounding air producing sound whether of an audible or inaudible frequency. Sound is the generalised name given to “acoustic waves”. Sound transducers can detect these acoustic waves which have frequencies ranging from just 1Hz up to many tens of thousands of Hertz with…

DC Motors are electromechanical devices which use the interaction of magnetic fields and conductors to convert the electrical energy into rotary mechanical energy. Electrical DC Motors are continuous actuators that convert electrical energy into mechanical energy. The DC motor achieves this by producing a continuous angular rotation that can be used to rotate pumps, fans, compressors,…

Another type of electromagnetic actuator that converts an electrical signal into a magnetic field producing a linear motion is called the Linear Solenoid. The linear solenoid actuator works on the same basic principal as the electromechanical relay seen in the previous tutorial and just like relays, they can also be switched and controlled using bipolar transistors or MOSFET’s.…

Electrical relays and contactors use a low level control signal to switch a much higher voltage or current supply using a numer of different contact arrangements. Thus far we have seen a selection of Input devices that can be used to detect or “sense” a variety of physical variables and signals and are therefore called Sensors. But there…

Light Sensors are photoelectric devices that convert light energy (photons) whether visible or infra-red light into an electrical (electrons) signal. A Light Sensor generates an output signal indicating the intensity of light by measuring the radiant energy that exists in a very narrow range of frequencies basically called “light”, and which ranges in frequency from “Infra-red” to…

The most commonly used type of all the sensors are those types of sensors which detect Temperature or heat. These types of temperature sensor vary from simple ON/OFF thermostatic devices which control a domestic hot water heating system to highly sensitive semiconductor types that can control complex process control furnace plants. We remember from our school science…

In this tutorial we will look at a variety of devices which are classed as Input Devices and are therefore called “Sensors” and in particular those sensors which are Positional in nature. As their name implies, the Position Sensor detects the position of something which means that they are referenced either to or from some fixed point or position. These types…

Simple stand alone electronic circuits can be made to repeatedly flash a light or play a musical note. Sensors and transducers are input and output devices respectively that can be incorporated into an electronic circuit or system allowing it to measure or change its surrounding environment. But for an electronic circuit or system to perform…