Output transducers are components that convert convert electrical energy into another form of energy. They are always Polarised (Positive & Negative)


The Light Emitting Diode (LED) is a diode with a gap between its anode and cathode which is bridged by a small filament wire. The material the wire is made from produces coloured photons of light when a small voltage (3V) is applied through electroluminescence. Electrical energy convert into light

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A Lamp or Signal Lamp is a source of incandescent light which has a filament wire between the positive and negative. When a electrical current is applied the wire heats to high temperatures and glows producing light. The gas inside the bulb prevents oxidation. Electrical energy into heat/light

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A Seven Segment display is a array of 8 LED's within a silicon casing that are laid out in the shape of a digital 8 with a decimal. Each LED shares a cathode and their individual anodes can be controlled to display numbers 0-9. Each LED segment only requires a low current.Electrical energy to light

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The Dot-Matrix display is an array of multiple LED's in a silicon case much like a seven segment. Its LED's are arranged in a matrix which can be controlled to individually turn on each of all in a row at once. Anodes are arranged at the Row and Cathodes at the columnsElectrical energy to light

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A Bargraph display is a vertical array of LED's in a silicon DIL casing. Each segment of the bargraph can be independently controlled as it has a separate Anode and Cathode. Often used to display levels of analogue inputs when paired with a suitable IC.Electrical energy to light energy

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A Piezo Transducer is a piezoelectric crystal which oscillates at a frequency depending on the current applied. The quartz crystal used allows for a range of frequency tones that can be controlled by an IC of PIC as polyphonic sounds.Electrical energy to sound energy

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A Buzzer is a Piezoelectric component that produces sound when a current is applied. An IC inside the case causes the piezo to oscillate at a specific frequency to produce a constant tone sound. Typically a 6V supply is required. Electrical energy to sound energy

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Siren is another Piezoelectric component that produces sound when a current is applied. An IC inside the case causes the piezo to oscillate between a low and high frequencies to produce a continuous sound . Typically a 9V supply is required. Electrical energy to sound energy

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A Bell is an electromagnetic component which has an actuator arm on a spring and metal gong. When a current is applied the electromagnetic coil magnetises moving the actuator to hit the gong and vibrate on the spring causing a short high pitch ringing. Electrical energy to mechanical energy

--------------------------------------------------------------------------------------------------------------A Loudspeaker is an  electro-acoustic device which when a current is applied to coil above a magnet it vibrates a diaphragm to produce sound waves. The speaker requires an alternating current to produce sound which is typically amplifed by a separate IC. Converts electrical energy into sound

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A Solenoid is an electromagnetic lock that when a current is applied energises a magnetic coil to move a metallic core back and forth. There are 2 types depending on the required; Push (locks) & Pull (unlocks). They require high current & typically 12V .Electrical energy to linear motion

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A Relay is an electromagnetic switch which can be used to interface between circuits with differing voltages. On one side is an electromagnetic coil of wire which when energised causes the metal switch contacts to move together and connect the other circuit. Converts electrical to mechanical

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A DC (direct current) Motor is a electromagnetic component that when energised causes the drive shaft in the centre to spin due to a controlled magnetic field. The timing of each coil turning on propels the drive shaft around at high speed (RPM). Converts electrical to mechanical


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Component Theory - Output Transducers

​​​​​​Mr BILLINGTON