With this project/application, you can make a light sensor dependent lamp. You can make a light sensor or dark sensor with this application. The light sensor of your Android smart phone senses ambient light present in your room and sends commands to Arduino board. Your Arduino program determines the behaviour of the LED, whether it…
Here’s a simple experiment with LDR and CD4093. This is just a modification of a previous project “dark sensor using 2 transistors”. In this project, the CD4093 is configured in such a way that whenever you block light falling on LDR, the circuit starts blinking the LED D1. The flasher circuit does not get power…
This works same as the other dark detector circuit. When light is falling on LDR, its low resistance drives transistor Q1-BC547 into conduction. This keeps transistor Q2 cut-off due to low base bias. The D1-LED does not get power as long as ambient light falls on LDR. When the resistance of LDR becomes high in…
For the circuit to work as light operated musical bell, we need to connect the SW1- switch to N/C terminal of relay. LDR has to be kept in a dark case.
An automatic dark sensor can be made using a PNP transistor(BC557).
In this case, LDR has been replaced with capacitor C1-0.01uF and resistor R3-1K has been replaced with L1 & VC1. In place of a LED, a Piezo Diaphragm has been kept.
We just need to add inductor, capacitor and a piezo diaphragm to convert a dark detector to an AM radio.
A breadboard is a device for testing temporary electronics projects. Components used to test a circuit can be reused for other projects. None of the components are damaged.
Almost all people start to learn electronics using breadboard because it is the simplest way of making circuit. The photograph shows a typical small breadboard which is suitable for beginners building simple circuits with one or two ICs (chips).
