Everything for Electronics

Microcontrollers

AC Volt/Amp Meter with Web Interface

Work areas usually have multiple power strips ganged together and connected to the same outlet. Various devices are connected to these strips, including computers, lights, coffee pots, space heaters, etc. Environmentally conscious persons ask, “How much power does my work area consume?” Safety conscious persons ask, “Am I overloading my circuit?” Calculating the answers requires two basic measurements: the voltage supplied to the circuit, and the amperage consumed by the circuit. Measuring AC voltage and, particularly, amperage with a multimeter is a potentially dangerous diagnostic for laypersons.

Wouldn’t it be nice to have a self-contained volt/amp meter that displays the values on a webpage?

Parallel Processing with the Propeller FLiP

The Parallax Propeller chip is an impressive multi-core microcontroller ... and the Propeller FLiP board makes it even more powerful! See how to integrate these together in your projects.

Build a Digital Light Saber

Want to “paint with light?” This article explains in detail how you can build a low cost (<$100) microprocessor-controlled LED light saber that provides as much or more capabilities than professional light wands.

MakerPlot – The DIY Software Kit

If you use microcontrollers in your projects, imagine how helpful it would be to see the data in a graphical format, rather than just a series of numbers -- especially when debugging! MakerPlot does all of this and connects directly to your microcontroller’s serial port to display analog and digital data in graphical form; it’s DIY software for your microcontroller projects.

An ESP32 / Teensy 3.5 Super Clock

After creating an Internet connected digital clock using the Adafruit RA8875 driving an seven inch LCD display, I decided to step it up a notch and add several additional features including: the ability to set an alarm; a countdown timer for uses like monitoring an exercise program; a weather display to provide brief conditions at 10 different cities; a real time stock market report that gives the changing prices for a selection of stocks; and lastly (just for fun), a Mandelbrot fractal generator to produce those wonderful images.

DIY Biotech: A Spectrophotometer for Measuring Bacterial Growth

Build an Arduino-based spectrophotometer to explore how the optical density of bacteria suspended in a liquid can be used to measure the rate and stage of bacteria growth.

Libraries and Headers in C: A Tutorial

If you’ve written a program for a microcontroller board such as the Arduino, Raspberry Pi, or Propeller QuickStart, you have relied on software libraries that provide constants and functions.  Often, we use software libraries without thinking much about them. Even if you never create a library, you probably want to know how they work and what they contain. This tutorial provides information that gives you a good start.

Build the Graphing Thermometer

Recently, I began to explore ways to improve and upgrade my “thermal monitoring technology” and came up with this simple, easy to build trend-plotting thermometer. This project features a large color graphics display to show the current temperature in big bold digits. Better than that, it also graphs the temperature trends over the most recent 4, 8, 16, or 24 hour period. 

Whether it be temperature trends, time and date, current/voltage readings, battery status, or other variables, consider giving your next project some extra pizazz by including an LCD color graphics display into the design!

An ESP8266 Live Wi-Fi Webcam

Having read about the ESP8266 NTP clock in previous issues of Nuts & Volts, an idea came to mind to construct an interface camera using the ESP8266. In this project, we used an old Android phone as a camera source and linked to an ESP8266 based webserver. The phone acts as a camera server and the ESP8266 web server acts as a client to the camera server. The webserver displays the live webcam on its web page.

Build the Laser Pencil Engraver

Several months ago, an idea popped into my head for a fun project. I wondered if I could burn some characters into the yellow paint of a No. 2 pencil with one of those powerful diode lasers available on eBay. Perhaps it could be my name or my grandkid’s names, or even a happy birthday message to my lovely wife. Here’s how I did it.