By T.K. Hareendran

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

LED Exit Sign

Interior signage such as lighted exit signs, plays an important role in keeping clients and staff safe during an emergency. This post shares the design idea of a simple and economical LED exit sign. This […]

High Water Sensor

Here is a simple high water sensor system to prevent costly to correct undetected water damage such as that caused by leaking pipes or corroded water heaters. The high water sensor circuitry will detect any […]

Variable Zener Diode DIY

A zener diode is often used as a simple voltage reference device. This post looks at how to create a variable (or adjustable) zener diode. Apparently, you can purchase the long-familiar programmable precision voltage reference […]

Lighted Cone Marker

I recently received a request to share some simplest ideas for converting regular cone markers to lighted cone markers. So, this post explains an idea to make your own lighted cone markers using a handful […]

Ultrasonic Proximity Sensor Arduino

So, here is another easy-to-build ultrasonic proximity sensor based on Arduino to detect objects made from various materials regardless of their shape, colour, or surface contour. Thanks, it operates using high-frequency sound waves that are […]

MH-SR602 PIR Motion Sensor Guide

A passive infrared (PIR) motion sensor allows you to sense motion, almost always used to detect whether a human has moved in or out of its range. For many do-it-yourself projects or devices that need […]

Glowing LED Eyes & Jawa Doll

Whether you are a novice or a seasoned crafter, crafting is a great way to get creative and pass the time. It is even better when you can incorporate some electronics. So in this post, […]

Phototransistor Secrets PT334-6C

In this post, you will get acquainted with a pretty popular budget phototransistor PT334-6C which is in fact a high-speed and highly sensitive silicon NPN epitaxial planar phototransistor available in a standard 5mm LED package. […]

Flickering Torch Bulb

What is the simplest circuit you can think of for building a flickering torch bulb or torch bulb flasher/blinker? How many components do you need? This little circuit uses only a few common components, no […]