In this article I have explained how to make a low cost yet fully automatic hand sanitizer dispenser circuit which will allow a touch-free or contactless dispensing of the sanitizing liquid on the user’s hands. This contactless hand sanitizer circuit facilitates the user to access the sanitizing liquid on hands automatically without the need of […]
Automatic
2 Simple Automatic Transfer Switch (ATS) Circuits
In this article we investigate an ATS circuit for initiating an automatic changeover from mains supply to generator supply through many intermediate transfer stages which involves activating the fuel valve, choke valve and the generator starter. The circuit was requested by Mr. Hari, and another dedicated reader from this blog. Requirement for 5kva LPG Generator […]
Making an Automatic Stopwatch for Runners, Athletes and Sportpersons
In this post I will show how to construct a stopwatch which automatically starts timer when the runner begins to run and the timer stops when the runner reaches the end. The elapsed time between starting and ending point is displayed on a 16 x 2 LCD. First let’s begin by learning how to configure […]
One Transistor Automatic Battery Charger Circuit
This one transistor cheap battery charger circuit is designed to automatically switch OFF the supply to the battery as soon as the battery has reached its full charge level. A very simple single transistor automatic battery charger circuit is I have I have explained in this article, which uses just a single transistor for the […]
Simple 48V Automatic Battery Charger Circuit
The proposed 48 V automatic battery charger circuit will charge any 48 V battery up to an optimal 56 V full charge level, utilizing very ordinary components. The circuit is highly accurate with its over charge cut off features. Circuit Description: As shown in the circuit diagram, the main element in the circuit is the opamp IC 741, which has been arranged as a comparator. Pin#3 […]
5 Best 6V 4Ah Automatic Battery Charger Circuits Using Relay and MOSFET
The following 5 versions of 6 volt 4 AH battery charger circuits has been designed by me and posted here in response to the request from Mr. Raja, I have explained the whole conversation. Technical Specifications “Dear sir, please post a circuit to charge 6 volt 3.5 ah lead acid battery from 12 volt battery. […]





