Little LED Marker Light DIY
Inspired by some commercial automotive side marker lights, I recently built a general purpose 3-LED flashing marker light. It can be used as an attention light in and around your home, especially at night. So, […]
Steady Hand Game – STEM
Steady Hand Game, also known as Buzz Wire Loop Game is a tabletop game which involves guiding a metal ring (the wand) along a serpentine length of bare wire (the loop) without touching the wand […]
Touchless Live Wire Detector – STEM Fun
This post explains how to make a simple touchless live wire detector that can be used to find hidden electrical wiring in a wall or ceiling. This battery powered tester is actually a very simple […]
Photosensitive Bristlebot – STEM Edition
Bristlebot is a great easy way for kids to start to learn basic electronics. Bristlebot is perhaps the simplest form of a walking robot with a rigid bristle toothbrush body. It seems simple, a Bristlebot […]
Another 555 Timer IC Electronic Latch Switch
You may not know the name of one of the first independent semiconductor designers, but you have encountered Hans Camenzind’s designs countless times. Incredibly, he created the 555 timer chip alone, spending a year designing […]
Mercury Tilt Switch Fun
As you know, a mercury switch can be used to detect any inclination with respect to gravity. For example, suppose your home security alarm wants to know when someone opens the lid of your cash […]
Automatic USB Mains Switch (v1)
Recently I wanted to build a USB controlled power strip that powers some peripherals as soon as my computer starts up. Luckily, I managed to find a commercial USB-Power On switch in my attic (see […]
6V Battery Guard Relay Module
Many of the newer robotic toys for kids now use 1.5V AA or AAA batteries as the power source. And it is a common practice to wire them in series to get a healthy 6VDC […]
5V Microcontroller Power Rail Guard
This 5V microcontroller power rail guard is a quite simple solution to add an overvoltage protection (OVP) mechanism between the 5VDC power source and your microcontroller board. In short, this little design uses a Zener […]
Doorbell Sensor IoT Module (v1)
In this post, I will attempt to share the design idea of a doorbell sensor that can be build using just a handful of inexpensive and easily available electronics components. When cleverly integrated into your […]