First of all, continuity testing is very important in electronics work, as it helps to find broken wires easily and it also helps to check PCB tracks. Sometimes wires look good but contain internal breaks, so technicians use a continuity tester to check them, hence, this simple Continuity Tester Circuit using an Op-Amp uses an […]
Transistor Based Water Level Alarm Circuit
Sometimes the water tank becomes full, but we forget to switch OFF the motor, as a result, the system wastes water; so, this simple Transistor Based Water Level Alarm Circuit is useful, as it gives sound alert when water reaches a level. Moreover, the circuit is cheap and easy to build as it uses very […]
Simple Two Transistor Buzzer Circuit
A buzzer is a small sound-producing device that designers use in alarms, toys, and indicators; also this Simple Two Transistor Buzzer Circuit uses only two transistors, making it simple to build and ideal for beginners. Furthermore, it works with low voltage and because of this it is safe to test, so let us understand the […]
12V Battery Low Voltage Alarm Circuit
Batteries play an important role in many electronic systems; however, their voltage drops over time, and if it falls too low, the battery may become damaged. So low voltage indication needed. Therefore, this 12 V Battery Low Voltage Alarm Circuit protects the battery by providing visual and audible alerts; also its simple, low-cost design uses […]
Low Voltage Alert Circuit for 9V Battery
Battery power plays an important role in electronic circuits, but the battery voltage can drop without warning; as a result, devices may stop working suddenly, making a low-voltage alarm necessary. This Low Voltage Alert Circuit for 9V Battery gives warning when a 9V battery goes low, as it uses LM339 comparator IC and also uses […]
Digital Code Lock Circuit using IC 4017
Security plays a very important role in todays world, therefore electronic code locks are very useful, as this Digital Code Lock Circuit using IC 4017 is a simple; as it uses push buttons, diodes, resistors, capacitor and IC CD 4017 . Moreover, this low cost circuit is easy to build, operates from a 9 V […]