By T.K. Hareendran

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

Breathing New Life into BLDC Motors

It’s damn sure, there’s plenty of old optical and magnetic disc drives (CD/DVD/HDD) in every electronics/hardware hobbyist’s junk box. Sadly it’s known to few people that such disc drives are rich and cheap sources of […]

Optical Smoke Alarm

Optical smoke alarms, also known as photo-electric smoke alarms, are particularly useful in bedrooms, lounges, hallways, and in other areas where we can otherwise expect false alarms from the common ionization smoke alarms. An optical […]

Digital Pulse Counter

Recently I came to understand the true demand for a multi-purpose digital pulse counter. So I designed an east-to-build digital pulse counter circuit based on some generally available cheap electronic components. The quick microcontroller based […]

Travel Door Sentry

Here’s a travel door sentry to safeguard your hotel room with a simple door sensor that will trip a warning alarm if anyone unlocks the door and intrudes. The battery-operated portable security device is very […]

Nifty NiMH Battery Charger

And now another interesting little project. After seeing numerous online projects I decided to build my own simple NiMH battery charger circuit using NiMH batteries because a bunch of GP2100 series NiMH cells are lying on […]

DHT11 Sensor Primer

In this guide we will learn how to play with a cheap ‘n’ cheerful temperature and humidity sensor DHT11 – the minuscule 4-pin sensor accurate enough for most do it yourself projects need to read […]