Ultrasonic range finder on breadboard using Arduino, DYP-ME007 and NE555
Ultrasonic range finder on breadboard.
Read More
Dark sensor using two transistors
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
Light operated switch works with NE555 timer and light dependent resistor. It uses relay and toggle switch idea for operation.
Remote Operated Switch
When you press an infrared transmitter or normal TV remote control near TSOP1738 infrared sensor, the 555 timer configured in monostable mode gets triggered.
Burning Arduino bootloader using Tiny
Step 1: Download USBtinyISP driver software from Adafruit.com. Install the driver for the USBtiny device. Then, insert the new Atmega328P-PU chip on the DIL socket of Arduino board. Connect the USBtiny device to Arduino. 🛠️ Dive into our collection of DIY Kits, 🔊 Audio Amplifiers, Digital Scoreboards, FM transmitters, and more! 🎶 Explore endless possibilities at…
Making Yoghurt with a Portlet
An Arduino based programmable outlet with screen and thermocouple inputs for implementing a wide range of awesome projects ! About PortletMake Yoghurt using PortletSupport this projectVideoImages KICKSTARTER PAGE: http://kck.st/1xuz7Ev A portlet is an Arduino based programmable outlet with screen and thermocouple inputs for implementing a wide range of awesome projects ! The Portlet project began...
Read More 
Up Counter
An up counter simply counts from 0 to 9. We can use this circuit to make digital object counter. This circuit can also be used to make a digital clock.
Digital Object Counter using LDR and digital IC
555 timer configured in monostable mode is a simple automatic dark sensor circuit that gives output when light falling on LDR is blocked.
Basic RC circuit
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.
FM transmitter and Dark sensor
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.
Telephone misuse indicator
When the phone line is in idle condition (on hook), the full voltage of 48V DC from the exchange appears across the line. When the phone is engaged by lifting the hand set, the voltage across the line falls down to around 12V. Thus, under idle condition (48V), VR1 is adjusted to give a positive biasing voltage to the base of Q3. As Q3 conducts Q1 gets into reverse bias and stops conduction. If the phone is engaged, Q3 stops conducting due to voltage drop across the lines, and subsequently, Q1 and Q2 starts oscillating and beeping is heard. Thus, this circuit can be used as an indicator for telephone tapping and misuse by an unauthorized person.
Dark sensor using BC557
An automatic dark sensor can be made using a PNP transistor(BC557).
AM receiver from dark sensor
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.
Mode of NE555- Astable
This circuit has been configured in Astable mode. The output pulses are determined by the values of resistors R1, R2 and the timing capacitor C1. The formula for the frequency of pulses is: f= 1.44/[(R1+2R2)*C1].
Sound generator and Musical toy organ
One of the main objectives of LDR Engineering projects is to make students capable of developing their own logic for making devices. Here is an example that tells how LDR Engineering helps in developing ideas.
