In this article we look into a simple 220V mains PWM controlled fan or light regulator circuit which does not require a microcontroller or costly triac drivers for the intended operations. Capacitive Phase Chopping All Ordinary types fan regulator and dimmers which rely on capacitive phase chopping technology have one drawback in common, these generate […]
Newly Updated Circuit Projects:
Make this 18V Cordless Drill Battery Charger Circuit
In this post I have explained how to build and use a 18V battery charger circuit for a cordless drill machine. The idea was requested by Mr. Chibuzo. Technical Specifications The Design Whether it’s a lead acid battery, a Ni-Cd or a Li-ion, this multipurpose battery charger shown below can be applied for any of […]
Simple Walkie Talkie Circuit
In this article I have explained a simple walkie talkie circuit that can be easily built by any hobbyist and used for communicating between rooms or floors or simply for having some fun across neighbors and friends. The range of this system is around 30 meters. A walkie-talkie, also commonly referred to as handheld transceiver is […]
Simple Digital Stopwatch Circuit (4-Digit)
In this article we’ll study a digital stopwatch design configured around the very popular IC LM555 in conjunction with a 4-digit counter IC with multiplexed 7-segment output drivers (MM74C926). Written and Submitted by: Jennifer Goldy Circuit Operation IC MM74C926 is internally made up of a 4-digit counter, an output latch up stage, a npn output […]
7 Interesting IC 555 Siren and Alarm Circuits
In this post I have explained how to use IC 555 to create 7 interesting siren and alarm sound effect generator circuits. The versatile astable multivbrator configuration of IC 555 allows us to implement it for making various types of sirens and alarm circuits. This becomes possible because an astable is basically a waveform generator, […]
Grid Mains to Generator Changeover Relay Circuit
In this post I have explained a simple configuration which can be used as a automatic changeover circuit for switching AC grid mains to generator mains, during power failures or outages. The explained circuit will effectively switch the connected appliances to the generator mains during power failure however it won’t be able to switch start the generator automatically, […]