Everything for Electronics

Tutorials

For IoT Projects, Call JSON

Internet-of-Things (IoT) projects that use sensors, actuators, displays, or controllers can easily communicate through an MQTT (Message Queuing Telemetry Transport) server, or broker. The MQTT standard lets devices publish and subscribe to specific topics. When they use the JavaScript Object Notation (JSON) format to exchange information, software can easily interpret or parse it. In this tutorial, I'll explain how to create and parse JSON messages.

Nextion Touch Screen Display — Part 2

In the first article, we downloaded the Nextion IDE, built a couple screens with various objects, and tested it in simulation. For this installment, we’ll actually be loading software onto a real Nextion TFT display and interacting with a PIC16F1824 microcontroller programmed with ME Labs PBP3 BASIC software. Finally, it will be tested on a breadboard.

Nextion Touch Screen Display — Part 1

Touch screens are fast becoming the “standard” for use in your homebrew projects. One of the more popular ones is the Nextion unit. In this first installment of a tutorial series, we’ll download the Nextion IDE Editing Software, load several prefabbed objects, and check our work on a simulator.

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.

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.

When you start to write libraries, it takes time to read documents, follow directions, and experiment with simple functions. Fortunately, after you understand how to create libraries and header files for the software tools you use, you'll have a useful skill that can simplify programming tasks.

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.

CNC Routers: Backlash

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.

The Smith Chart

The Smith Chart turns the complex mathematics of transmission lines into circles and arcs that unlock the mysteries of SWR, stubs, matching networks, and a whole lot more. It’s an amazing tool that brings the arcane math of transmission lines to visual life so you can understand them.

More Tricks with Old-School Digital Clocks

Here are a few of the many possible variations on the general theme of discrete-logic digital clocks. If you have a few LED displays, counters, drivers, and simple logic, you can probably build a clock. Consult the datasheets of the ICs you choose to use, breadboard everything first, and have fun.

How Phased Array Antennas Work

Phased arrays have been used for years in military radars for long range detection of missiles. They’re also widely used in military and commercial aircraft radars and some satellites. These phased arrays are expensive, but today thanks to new technology and higher frequencies, phased arrays are smaller and more affordable making them practical for new wireless devices. This article is an introductory tutorial on this special antenna type you need to know about.

Filter Basics: Stop, Block, and Roll(off)

A casual observer might think that wireless systems consist primarily of filters connected by the occasional bit of circuit. Block diagrams of transceivers often include as many filters as any other function. This is true at the system level, just as it is at the circuit level — and many circuits behave in a filter-like way, whether intended to be a filter or not! That makes understanding filter basics important for wireless success.