By T.K. Hareendran

International Electronic Design Freelancer • Technical Author • Hardware βeta Tester • Product Reviewer
Articles Written 457

Poor man’s USB Rubber Ducky

I believe most readers are familiar with Hak5’s USB Rubbery Ducky. Well, simply it is a $45 key stroke injection tool, masked as a generic usb flash drive, widely used to hack unlocked computers. Computers […]

USB Power Bank Adapter

USB Power Bank – popularly known as mobile phone emergency charger – is an ideal solution for powering small microcontroller based hobby projects. Even the cheapest power bank in the market has so many useful […]

Poor man’s 433MHz RF Sniffer

Nowadays minuscule 433MHz RF modules are used in a wide variety of applications that require wireless control, and are very popular among the tinkerers because these modules are very cheap and can be interfaced easily […]

Secure Water Pump Switch

Here is the circuit diagram of an independent water pump switch controller with ‘soft’ on/off buttons. Since the circuit uses low-voltage switches, even a kid can operate it safely. Besides, there’s also a dry-run protection […]

Safe Bathroom Lamp Controller

As you may know, bathroom is possibly the most dangerous area in your house when it comes to electrical safety because water is a sound electrical conductor. The consequence of an electric shock is far […]

Electronic Magnet Evaluator

Electronic Magnet Evaluator is a simple device incredibly useful for experimenters and students. With this little gadget one can not only detect the presence of a permanent magnet but also find out its south (S) […]

Security System with Voice Playback

This circuit is designed in response to a request made by my beautiful neighbor. What she desired was an inexpensive device to record and replay customized voice messages. Now it’s the frontend of her simple […]

Simple Flood Alarm

The electronic flood alarm circuit presented here is wired around an LMC555N (IC1) – CMOS version of the bipolar 555 timer chip. IC1 is followed by a complimentary pair of emitter followers (T1 and T2) […]