When RF energy travels in a transmission line and encounters a load or different type of line, the resulting reflections create standing waves of voltage and current, just as water waves do when they encounter an obstruction. This can create problems with digital signals and can result in extra losses. However, there are several techniques for dealing with these reflections.
Any conductor carrying an AC current can be treated as a transmission line. Here, we'll talk about a basic element of transmission lines: the standing wave ratio. Find out why it’s important and how to measure it.
I can hardly imagine an electronics enthusiast without some sort of test bench. This can be as simple as a folding table and a couple of hand tools, along with a cheap DMM (Digital MultiMeter). Or, it can be as elaborate as a spare room just loaded with TE and a full complement of tools and accessories to go with it.
Construction articles found in electronics magazines use printed circuit boards for all but the simplest circuits, so investing time and money into the PC board fabrication process seems to be the next logical step, albeit a bit daunting for the new hobbyist. PC board fabrication is not necessarily the next step. There is another alternative … wire wrap.
The phenomenon known as RF interference — RFI to its many friends and acquaintances — involves interference caused by signals propagated wirelessly as radio waves. Most people don’t know (or care) about RFI until their garage door opener won’t work.
Rings, beads, cores ... find out exactly what ferrite is and what makes it ideal for a variety of uses in electronics. First created in 1930, they have since become important materials in the electronics and RF world.
Listening to shortwave radio is very interesting, and filled with the voices and music of far-off lands. Digging a bit deeper, there is another world of shortwave radio that does not use conventional sounds. It is the realm of data transmissions.
Even though they're ancient by today's standards, old tube radios can almost always be brought back to life, and there's still plenty of broadcasts out there for them to receive! Not to mention, they just look so classy and have a presence few modern electronics can match.
Whether you need to flash an LED, energize a relay, turn a buzzer or alarm on or off, or invert a voltage level, the NPN transistor switch can easily solve your problem. This article shows you how to use a transistor as a simple SPST switch.
Most electronic devices today have a single button you push to turn them on and off. Think of your cell phone, laptop, and even your TV. There is no toggle to flip, no knob to turn back and forth, nor slide switch to move. So, how do you get one of these power buttons into your project so your latest gadget can sit next to your other devices without the embarrassment of a toggle or slide switch?
