The post describes simple battery charge monitor circuits or battery status circuits. The first design is a 4 LED voltage monitor circuit using the versatile IC LM324. The idea was requested by Ms. Piyali. Technical Specifications I’ve a project, if you could help me out: 1. basically its a battery voltage detector cum indicator circuit. […]
Sensors and Detectors
Non-Contact Cable Tracer Circuit
In this post I have explained a simple non-contact cable tracer circuit which can be used for locating faults in long wound cables and wire bundles without a physical contact. The Circuit Concept Why would you shred $100 to buy a cable tracer when it is easier to develop one spending less than $10! This […]
IC 555 Low Battery Indicator Circuit
In this article I have explained a simple low battery indicator circuit using the IC 555 and a few resistors only. Circuit Concept Many electronic circuits such as emergency lights, battery chargers, UPS systems, flashlights etc essentially require a low battery indication feature in order to avoid over discharge of the involved battery. An over discharge could mean a permanent damage […]
Very Low Frequency (VLF) Detector Circuit
Low frequencies predominantly cover our earth’s atmosphere. This range of frequency may be created by many different sources which may be quite unknown and strange. A VLF sensor equipment can be made to trace these frequencies for investigating the intriguing secrets hidden behind it. Mr. Steven Chiverton investigates. VLF Receiver for Sensing Lightening and other […]
How to Make LED/LDR Opto Coupler
Ever needed an application where the resistance of a resistor needed to vary proportionately in response to a PWM or a varying analog voltage? Yes, this is where an LED-LDR opto-coupler becomes so useful. The following image shows the symbol for a LED LDR opto-coupler. Any other regular opto-coupler, such as an LED/transistor, LED/FET, or […]
Make this EMF Pump Circuit and Go Ghost Hunting
EMF pump circuits are devices which are popularly used for the purpose of identifying paranormal activities or entities by generating rapidly rotating magnetic fluxes in the ether. The conventional devices use a spinning magnet fixed over a motor spindle, however these are mechanical types and are prone to wear and tear. Introduction The explained circuit […]
