The 5 simple fastest finger first indicator circuits presented here can be used for indicating which candidate was the first to press the answer button out of the 4 participating candidates in a quiz contest. We all have probably seen the famous game show “who wants to be a millionaire” and many similar quiz shows, […]
Simple
5 Simple Power Bank Circuits for Mobile Phones
In this article I have explained a 5 assorted power bank circuits using 1.5V cell and 3.7V Li-ion cell which can be built by any individual for their personal emergency cellphone charging functionality. The idea was requested by Mr. Irfan What is a Power Bank Power bank is a battery pack which is used to […]
Simple Motorcycle Security Alarm Circuit
In this article I have explained a simple motorcycle ant-theft security alarm circuit using a tilt switch and a TTP223 touch switch. The circuit was requested by Mr. Sergei, as given below. Design Request and Specifications I am a motorcyclist and I would like to ask you to design a simple and cheap alarm system […]
Simple LDR Motion Detector Alarm Circuit
Here I have explained how to build a simple LDR based motion detector sensor circuit using ordinary parts such as LDRs and opamps, reasonably accurately. What are Motion Detectors Motion detector or sensor alarm is a device which detects the presence of a motion or movement within a certain fixed range and raises an alarm […]
Simple RGB LED Controller Circuit
In this post I have explained how to make a simple RGB (Red, Green, Blue) LED controller circuit which may be designated to flash a group of RGB LEDs with a particular sequencing pattern. The idea was requested by Mr. Navdeep. Technical Specifications I want to make a display board with red, green and blue […]
Simple Electronic Dog Whistle Circuit Explained
An electronic dog whistle is a device that generates ultrasonic sound waves and is used for training dogs and for controlling excessive barking habit. Because dogs and domestic cats can hear ultrasonic frequencies, humans cannot, this dog whistle device is employed to train these animals. It is also sometimes known as a silent whistle or […]





