Battery power is very important in electronic circuits. But many times a battery voltage becomes low without notice. As a result, devices stop working suddenly and therefore, a low voltage alarm is needed. This Low Voltage Alert Circuit for 9V Battery gives warning when a 9V battery goes low. It uses LM339 comparator IC and […]
Digital Code Lock Circuit using IC 4017
Security plays a very important role in todays world, therefore electronic code locks are very useful. This Digital Code Lock Circuit using IC 4017 is a simple. It uses push buttons, diodes, resistors, capacitor and IC CD 4017 . Moreover, it is low cost and easy to build and it works on 9V power supply. […]
Darkness Activated LED Circuit
This article explains about a Darkness Activated LED Circuit which is useful device that saves power. It is energy efficient circuit because light glows only in darkness. The circuit turns ON light at night and it turns OFF light in day time. It works fully automatic so, no manual switch is needed daily. It is […]
Fan Start 10 Second Delay Timer Circuit
In many homes and industries sometimes a fan does not turn ON immediately. A fan start delay timer is a circuit that delays the fan start. When power is applied the fan stays OFF and after some fixed time the fan turns ON automatically. In this circuit the delay time is about 10 seconds and […]
30 Minute Delay Timer Circuit using Transistors
This article explains a simple 30 Minute Delay Timer Circuit using Transistors. The circuit is with low cost and is easy to build. It uses common parts like BC547 transistors, resistor and capacitor. Because of simple design, beginners can also understand it easily. This circuit is useful where delayed switching is required. For example, light […]
Transistor Based Coin Toss Game Circuit
Sometimes we need to make a quick decision but choosing is not easy, so we flip a coin. Now imagine doing the same with electronics. This Transistor Based Coin Toss Game Circuit works like a real coin toss and it gives random result every time. When power is applied, no one knows the result. One […]