With the influx of electric skateboards and scooters that have taken over seemingly every city, I started thinking it might be something to purchase for myself. Instead, I decided that I would try to build my own from scratch. Not really to save money, but to gain the experience of building something of my own. The primary purpose of this article is to show my design and manufacturing process, so that you can learn from what I built.
Long exposure photography captures the path of light over time, smearing moving elements to produce a single photo which creates a new realm of artistic photography. However, popular subjects of light exposure photographs are uncontrollable (stars, car headlights, etc.), so we made a light painter using microcontrollers and a DotStar LED strip to develop custom photography from images uploaded by a user.
Now that I’ve retired, I’ve started experimenting with some of the analog subjects that I haven’t done much with since school back in the seventies. To begin with, I started with op-amp circuits; specifically, Colpitts oscillators. I built the circuit on one of those plug-in ‘protoboards,’ a ±15V power supply, an oscilloscope, and a multimeter. For my experimentation, I was using a trim pot. I would adjust until oscillation began, then power down, pull one end of the trim pot, measure the resistance, then re-connect, power up again, and continue adjusting until I reached the other end of the resistance range, where the oscillation would cease. I would then repeat the resistance measurement. That procedure was not ideal. In addition to the multiple tedious steps, adjusting a trim pot can be a pain. Enter my potentiometer box.
Most LED projects involve some wiring, some resistors, a solderless breadboard, and a bunch of jumper wires. Not this one! You can create bright, stunning colors by literally just plugging LEDs directly into the Arduino pins. No wiring, no resistors. Just your Arduino and a handful of LEDs. The is the absolute simplest and lowest cost way to get started manipulating light and color. I’ll show you how to do it safely in this article.
As a final class project for our “Digital Systems Design Using Microcontrollers” course we all took last semester at Cornell University, we created a very unique device. We wanted to design something fun, aesthetically pleasing, and interactive, and since we all enjoy listening to music, we decided on a music visualizer. Our vision was to create a unit that listens to music being played, then in real time displays a dynamic and colorful visual representation of the music based on the volume and pitch of the notes. Additionally, our music visualizer provides an alternate avenue for experiencing music for the hearing impaired. Here’s how we did it, so you can make one too!
One hobby that’s prevalent today is restoring antique radios. Once you have an antique radio, it’s nice to listen to it. Unfortunately, the content of present day AM radio stations leaves a lot to be desired. There’s nothing comparable to the type of programming that was on the air in the heyday of radio broadcasting. The solution to this dilemma is to use a low power crystal-controlled AM transmitter to broadcast age-appropriate material to the antique radio. Such an AM transmitter is the subject of this article.
If you care about the weather and enjoy creating graphs that give all kinds of details, then you’ll really enjoy this sequel to the original graphing thermometer presented in Issue-2 2019. Features include outdoor and indoor temperature, outdoor and indoor humidity, wind speed, wind direction, rainfall, and barometric pressure.
Wouldn’t it be handy if you remembered to bring everything you need when you leave home without having to remember to remind yourself to remember? Well, the MEMO_BOX is just what you need! It will alert you with custom messages with its motion detector when you pass by it when you leave your house. Plus, you can use the motion detector to do other things like set off a recording of spooky sounds to delight trick-or-treaters when they come to your front door.
Many of us have fond memories of assembling sections of track and spending many enjoyable hours racing slot cars, either alone or with friends. Maybe it’s a hobby you’d like to get back to (or never left) or share it with the next generation of slot-car racers in your family. Racing these miniature cars around a track is only part of the fun! With a little amount of expertise in electronics, there are definitely many accessories we can build ourselves — probably enough to fill at least a small book. Since we don’t have that much space here, I’ll highlight only a few of these project ideas.
Magnets are magic! To suspend something in air repelled by a magnetic field is a bit of a trick. We need some electronic control of the situation to stabilize magnetic levitation. See how I achieved this and made a castle float in the air. This project is sure to delight and mystify family and friends!