This is yet another dark sensor DIY kit. It is slightly different from other dark sensor kits. It has a buzzer and a photodiode that makes it different from other kits. Along with the LED, the kit turns on the buzzer whenever it senses darkness. See all the images below to get the idea for…
I have written several posts similar to this one before. This experiment is again about a dark sensor based on LDR or photoresistor. There are a few components and basic soldering experience should be enough to build this up. It is a good and easy kit for electronics beginners. 🛠️ Dive into our collection of…
The circuit is ready for testing. Connect battery terminals and see the output. As you block light falling on LDR(Light dependent resistor), the LED glows.
OUTPUT:
[youtube]http://www.youtube.com/watch?v=qmWAgoHwy3w[/youtube]
THIS CIRCUIT IS EXTREMELY SENSITIVE TO DARKNESS. EXPERIMENT THE CIRCUIT IN A HIGHLY ILLUMINATED ROOM.
LED GLOWS EVEN IN LESS DARKNESS. Use torch light if the LED glows in less darkness. You can adjust the sensitivity of the circuit using a variable resistor in place of R3-300Ohm. Try this circuit with other resistances as well, for example, 1K, 10K and 100K, etc.
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…
Description: This versatile 741 operational amplifier module can be used for making a dark detector using an LDR, a photo transistor and a photo diode. The amplifier has been configured in inverting mode. It compares the change in voltage at pin 2 with the reference voltage at pin 3 and gives output at pin 6…
Description: In this clap switch we use three different modules given below. It is necessary to make these three modules in order to make a clap switch. a. Dark sensor using 2 transistors. b. Monostable mode of 555 timer. c. Toggle switch using 555 timer.
Description: LM358 is also one of the types of operational amplifier. LM358 consists of two independent, high-gain, frequency-compensated operational amplifiers designed to operate from a single supply over a wide range of voltages. This module can also be used for testing an LDR, a phototransistor and a photodiode. You just need to replace an LDR with…
Description: In the monostable mode, the 555 works as a “one-shot” pulse generator. Other applications of monostable mode include timers, pulse-width modulation (PWM), missing pulse detection, touch switches, frequency divider, capacitance measurement, bouncefree switches and so on.
Here’s a simple light activated police siren using light dependent resistor and NE555 timer. Before you make this project, I would recommend you to make the following projects. a. Light sensor and dark sensor I strongly recommend you to make a dark sensor and light sensor using LDR and understand clearly how it works. b….
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…
Light operated switch works with NE555 timer and light dependent resistor. It uses relay and toggle switch idea for operation.
When you press an infrared transmitter or normal TV remote control near TSOP1738 infrared sensor, the 555 timer configured in monostable mode gets triggered.
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.
A dark sensor can be converted to a simple FM transmitter using the following components. This FM transmitter is very sensitive and it has transmitting range of 30 meters.
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.
To make an object counter we can use a simple dark detector circuit and a normal calculator. Pole and NO (Normally Open) terminals of a relay have to be connected to the two pins which are used to activate ‘=’ key of calculator.
As we block the light falling on LDR, the calculator starts counting.
For the calculator to work as a counter, we first need to press ‘1’ and ‘+’ keys.
A multivibrator is an electronic circuit used to implement a variety of simple two-state systems such as light
emitting diodes, timers and flip-flops.
Remote tester circuit also resembles the logic of a “dark sensor (using BC557)”. LDR has been replaced with IR sensor TSOP 1738. The circuit works as a remote tester. Pressing a remote control switch near the IR sensor, switches on the LED D2.
