In this article I have explained how to make a simple 2-step Arduino programmable timer circuit, which can be used to switch an electrical load ON/OFF with independently adjustable ON and OFF timings. For example if you want a light to remain ON for 24 hours and OFF for 2 hours, you can simply do […]
Archives for 2020
Simple Low Dropout Regulator Circuits Explained
The transistorized low dropout voltage regulator circuit ideas explained in the following article can be used for getting stabilized output voltages right from 3 V and above, such as 5 V, 8 V, 9 V, 12 V, etc with an extremely low dropout of 0.1 V. For example, if you make the proposed 5 V […]
10 Useful Function Generator Circuit Diagrams Explained
In this post I have explained how to build 10 simple yet useful function generator circuits using IC 4049, IC 8038, IC 741, IC 7400, transistors, UJTs etc. for generating accurate square waves, triangle waves, and sinewaves through easy switch operations. 1) Using IC 4049 Using only one low-cost CMOS IC 4049 and a handful […]
PIR Burglar Alarm Circuit
The PIR burglar alarm explained here will detect a human intruder within the stipulated range and sound an alarm. Thus, the system could be effectively use for detecting trespassing, theft, intrusion, burglars, or any form of unlawful entry inside a restricted area or zone. Basic Principle The operating principle of the proposed burglar alarm circuit […]
6 Best Ultrasonic Circuit Projects for Hobbyists and Engineers
In this post I have explained a 6 very useful yet simple ultrasonic transmitter and receiver circuit projects which can used for many crucial applications, such as ultrasonic remote control, burglar alarms, electronic door locks, and for listening to frequencies in the ultrasonic range which are normally inaudible to human ears. Introduction Many commercial ultrasonic […]
4 Useful Logic Probe Circuits Explored
These simple yet versatile 4 LED logic probe circuits can be used to test digital circuit boards such as CMOS, TTL or similar for troubleshooting the logic functions of the ICs and the associated stage. What is a Logic Probe A logic probe circuit is a handheld electronic tool which can be used to test […]





