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 […]
Handy Test Light (v1)
Get ready to make a high-resistance continuity tester pen that runs on a pair of common 1.5V AA batteries. This design is based on an idea from a Chinese website but with a few modifications. […]
hFE Test Connector/Adapter for Analog Multimeter
As mentioned in my previous post, some analog multimeters offer the hFE test feature via a custom-made hFE connector that is usually sold as an optional accessory. The popular Sanwa YX-361TR analog multimeter is a […]
Poor man’s Luxury Car Dome Light
If you often drive early in the morning or at night, you spend most of your time in a dark vehicle, and at that time a small interior/dome/cabin light becomes an indispensable widget if you […]
An Eternal LED Scarecrow
Recently, I wanted to try an electronic scarecrow in my lab window to scare off some birds (often nocturnal) that make a lot of noise and dirt. Although there are many options for building one, […]
Self-Lock Delay Switch Module DIY
Self-lock delay switch is a simple timer module that produces a fixed square pulse. It is designed around the 555 timer and uses a tricky negative edge trigger to ‘run and lock’ the timer. The […]
BYO Muddy Water Detector
The goal of this little post is to share an idea to build your own robust mud water detector using readily available inexpensive electronics components. Although unintentional, the sensor component in this design concept is […]
Midget USB LED Lamp – DIY
There is nothing amazing about looking at the design concept of a simple USB LED lamp, I know. But believe me, the midget USB LED lamp presented here has a little power reservoir in the […]
Matchbox Magic Lamp v1
This post is about the construction of a multi-colored matchbox-sized magic lamp for kids using a simple and cheap microcontroller board. The most interesting thing about this build is that it does not require any […]