Curtain Opener
Open or close the curtains of your house at the press of a switch. All you need is this electronic curtain opener. Meant for...
Super Simple Intercom
This intercom circuit based on IC LM380 audio amplifier requires very few external components. So the circuit is very easy to assemble.
Intercom circuit
Circuit diagram...
Water Pump Controller
Here is a simple water pump controller circuit for controlling the water level in an overhead tank. The main components of this pump controller...
Simple Sensitive Remote Control Tester
This handy remote control tester circuit for testing infrared-based remote control transmitters used for TVs and VCRs etc. The circuit is built around 7805 IC,...
Dew-Point Sensor
A dew sensor is used in sensitive electronic equipment like cameras and copiers etc, to protect them from moisture failure by fast detection of...
Strain Meter
This strain meter shows whether the strain is compressive (reducing the length) or tensile (increasing the length) when an object such as a strut...
Linear Timer For General Use
This simple linear timer can be used to control any electrical appliance that needs to be switched off after a certain time, like a...
Laser Based Communication System
In this circuit, an electrical signal is transmitted from one place to another riding over the laser beam.
Playing with Robotic Eye (IR Sensors)
There are various applications of IR sensors such as TV remote controllers, burglar alarms and object counters. Here we have used IR sensors (infrared...
Solar Battery Charging Indicator
Here is a battery charging indicator circuit of a simple charging monitor that indicates whether the storage battery of a solar power unit is...
Digitally Adjustable Dancing Lights
You might have come across several types of adjustable dancing lights (flickering LEDs). Most of them use presets (variable resistors) to adjust the rate...
Low-cost Stopwatch
Here is a simple circuit of a low-cost stopwatch that can count up to 99 seconds. The circuit uses CD4060, CD4013, CD4033, LTS543 and...
PC Power Manager
Very often we forget to switch off the connected peripherals like monitor, scanner and printer while switching off our PC. This leads to needless...
Crystal AM Transmitter
Here is the circuit of a medium power AM transmitter that delivers 100-150 mW of radio frequency (RF) power.
AM transmitter circuit
At the heart of...
Digital Soil Moisture Tester
Here is a simple and compact digital soil moisture tester to check whether the soil is dry or wet. It can also be used...
Multitone Siren
This multitone siren is useful for burglar alarms, reverse horns, etc. It produces five different audio tones and is much more ear-catching than a...
Overheating Indicator for Water Pipe
This circuit monitors the temperature of the water pipe. If the temperature of the pipe goes above certain limit, it flashes an LED.
Smart Laptop Docking Station
You can easily convert your ordinary docking station into a smart electronic laptop docking station with an anti-theft alarm. The circuit presented here can...