DIY Water Level Monitoring Circuit is good for tank or reservoir. It use IC 555 timer in astable mode and make repeated signal. When water reaches a set level then buzzer turns ON. The circuit helps to stop water overflow and is useful in home, factory and farm. Circuit Working: Parts List: Component Quantity Resistors […]
Tone Generator Doorbell Circuit using Dual IC 555 Timers
This tutorial is about Tone Generator Doorbell Circuit using Dual IC 555 timers. This circuit is simple and works well when button is pressed. One IC works in astable mode and other in monostable mode. It is very important for making sound to run a 8Ω speaker. The circuit needs 9V DC power and makes […]
9V Battery Powered Transistor Intercom Circuit
Intercom system is device for talking at short distance. 9V Battery Powered Transistor Intercom Circuit uses 9V battery which is good for home or office talk. It uses only transistors which is easy to understand and works well. The circuit has mic and small speaker as sound. BC547 transistors make sound loud and 2N2222 transistor […]
Transistor Based Battery Heater Circuit
Transistor Based Battery Heater Circuit uses 12V DC with good heat and very portable. Circuit is good for outdoor, no-electric place, small incubator and emergency heat. It uses astable multivibrator with transistors. Transistors switch power transistor and run heat coils. LED show if circuit is working. Circuit Working: Parts List: Component Value Quantity Resistors (All […]
Ultrasonic Mosquito Repellent Circuit
Mosquitoes are small bugs which are very annoying. They also spread bad sickness like malaria and dengue. This Ultrasonic Mosquito Repellent Circuit idea is to use high sound especially ultrasonic to above 20 kHz to scare mosquitoes. Ultrasonic sound can disturb them and make them go away. This simple circuit makes that sound. Mosquitoes do […]
Simple Boost Converter LED Torch Circuit using IC MAX660
Simple Boost Converter LED Torch Circuit using IC MAX660 is small but useful light tool. This project use MAX660 chip to make LED torch work well. MAX660 boost 3V battery to higher voltage and can light many LEDs. It is good for battery devices needing more voltage and with no inductor needed. Circuit design also […]