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| MAKING A LIGHT / DARK SENSOR | ||
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| PDF FILE - CLICK HERE FOR PRINTABLE WORKSHEET BASED ON EXERCISE BELOW | ||
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Opposite is a simple light/ dark sensor. This can be connected as an
input or switch to another circuit. The sensors has three green wires
(1, 2 and 3). Wire 2 should always be connected to one of the inputs. If
wire 1 is also connected then the sensor acts as a dark sensor. If wires
2 and 3 are connected to the inputs then sensor operates as a light
sensor.
The preset resistor allows the person using the circuit to alter its sensitivity to light/dark. |
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| CONSTRUCTING A CIRCUIT USING SIMULATION SOFTWARE | ||
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All circuits are drawn on software such as Crocodile Clips. Using this
software the individual components can be joined together on the screen.
Once the circuit is drawn its operation can be simulated to see if it
works. If it fails it can be corrected on the computer screen and tested
again. Using software to test circuit designs saves time as there is no need to physically solder together components. It also saves money as components and materials are not wasted on failed circuits |
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| The circuit is then made into a PCB (Printed Circuit Board). Components are added and soldered in position (See PCB Section of this website). Two views of the same circuit are shown below. How do they differ? | ||
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| 3. Complete the table below by writing some details about the components used in the light/dark sensor circuit. | ||
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