It took me eight months of part-time work to restore all 168 pounds of a Heathkit “H-1.” I would like to share a few of the trials and tribulations I went through to resurrect this beast.
This system monitors motion from a USB webcam on a Raspberry Pi 3 using the OpenCV API. Once movement is detected by the system, it takes a picture of what set the motion detection software off and emails that picture to you. It also affords you the ability to remotely view the webcam from an Android application from anywhere in the world at any time.
A dummy load is a resistor used to load any radio frequency generator/amplifier to simulate an antenna for testing purposes. It’s used to allow full power output while testing or experimenting without radiating a radio frequency signal. Here’s one you can build for less than $5.
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.
In the beginning, computers were very large and took up a lot of space. These days, single-board computers have gotten quite small. So, could an older Intel 8080 compatible computer be built to today’s smaller size standards? Why yes! It can!
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.
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.
Backlash can have a detrimental effect on tool life and on your CNC router’s ability to maintain accurate positioning of the X, Y, and Z axes. In this article, we’ll look at the problem of backlash in CNC routers. Once you understand what role it plays, you’ll want to diminish its impact on your machine. Whether you own or intend to build/buy a CNC router, make it a habit to routinely check for backlash. It could save you some money and/or aggravation.
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!
A voltage reference is a zener diode-like semiconductor that produces an accurate fixed voltage; often, five or 10 volts. The downside to a voltage reference is that it only generates a single voltage and has limited current output. I decided to design a circuit that could generate any voltage between zero volts and 10 volts in 0.1 volt increments. Here’s how I constructed my variable voltage regulator.