The whole Internet of Things (IoT) phenomenon has been around for a while now. But have you tried to create an IoT device on your own? If so, you know it’s not easy. However, it is now easier than ever as many of the manufacturers of IoT wireless chips and modules are providing the hardware and software to make an IoT device happen with minimum work. One example is the Wireless Xpress BGX13P module starter kit from Silicon Laboratories.
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.
When the concept of electromagnetic waves was first proposed around 1864, it was met with great skepticism. As a result, the idea languished for a long time. It took several decades for a handful of dedicated persons — infatuated with the mysteries of electricity and magnetism — to finally put the theory on a solid footing.
In this article, we’ll take a look back at this period that launched the serious study of radio waves. We’ll examine the contribution of James Clerk Maxwell, the man most responsible for the concept. Next, we’ll look at the work of several notable scientists who came after Maxwell, and see how they confirmed the existence of radio waves.
Most frequency counters can tolerate only low levels of RF at their input, but here’s a way to safely measure the frequency of an RF signal of up to 200 watts with your existing frequency counter.
There are a lot of technologies that got a start on some ham’s wireless workbench. Ham radio almost demands tinkering and inventing. Some creations get no farther than a one-time project, while others become the basis for companies and industries.
Rarely has there been as much interest in a high frequency radio as that shown to the Microbitx. Low power enthusiasts — better known as QRP operators as well as ham radio hobbyists — have rushed to place their order for this exciting and challenging new transceiver kit. Challenging in that it’s had a problematic chip “on its shoulders.”
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.