By T.K. Hareendran

International Electronic Design Freelancer • Technical Author • Hardware βeta Tester • Product Reviewer
Articles Written 464

Little Hydrophone

This article is about building a little hydrophone that can be used to record underwater sounds. Professional hydrophones used in science world are relatively costly, and even do it yourself ideas feature expensive components. As […]

3-Wire PC Fan Tips & Tricks

A fan failure in today’s advanced electronic projects may result in other delicate and expensive components failing, causing costly repairs and delays. A 3-wire PC fan is an easy and inexpensive way to prevent such […]

The NJK-5002C Hall-Effect Sensor Proximity Switch

Having spent a few days messing on with building simple inductive proximity sensor circuits, I’m putting together anew inductive proximity detector device for a small-scale industry. I already have an expandable idea with the sensor […]

Arduino Inside Automatic Staircase Light

Here’s an automatic minder to keep your stairway alighted while you’re near to it. One presence sensor wired to a microcontroller scans its environs and automatically activates a light source when it sees an object. […]

Charge-Pump Primer

If you build battery/usb powered electronics projects, often you’ll be in need of a high-voltage power supply. That is a power supply that has an output voltage higher than that catered by the battery. One […]

CMOS Toggle Switch with CD4049

Here’s a simple and clever way to build a toggle switch with a quite popular, highly available, and cheap CMOS logic chip CD4049UB. Since the little electronic toggle switch presented here is an easy to […]

An Easy 555 EC Sensor!

Aware that a particular circuit is needed to measure electrical conductivity (EC) of  a liquid. Since the conduction of current through a water solution is mainly dependent on the concentration of dissolved ionic substances such […]