How to Design a Microphone Amplifier
2020
Here’s how I made an amplifier for a short-range public address speaker.
You Don’t Have to Be an Engineer to Design Your Own Electronic Circuits
June 2019
Do your own designs with a little direction.
Dirt Cheap Wireless Control
Column:
Open Communication
May 2019
Have some fun experimenting with the wireless modules available out there for short-range applications.
Whatever Happened to these Wireless Technologies?
Column:
Open Communication
March 2019
A list of “forgotten” standards and services.
Waiting for 5G Wireless
Column:
Open Communication
February 2019
A status report on 5G to bring you up to speed.
IoT Made Easy
Column:
Open Communication
January 2019
It’s getting easier than ever to make your own stuff to connect to the Internet via IoT.
How Phased Array Antennas Work
Column:
Open Communication
September 2018
Introductory tutorial on a special antenna type you need to know about.
Seven Common Ways to Generate a Sine Wave
Column:
Open Communication
May 2018
There are literally dozens of ways to generate a sine wave. Here are some of the more popular methods you should be familiar with.
Connected Cars are Coming
Column:
Open Communication
February 2018
In the coming years, we will be seeing new wireless systems incorporated into every vehicle for improving safety and for aiding in the implementation of self-driving cars.
Personal Communications Services: The MURS Option
Column:
Open Communication
December 2017
You know about CB, FRS, GMRS, and FRS radios, but have you heard about MURS?
Going All The Way With QRP
Column:
Open Communication
October 2017
Talking around the world on a kilowatt is easy. How far can you go on less than one watt?
Going the Distance with Wireless
Column:
Open Communication
August 2017
Demands for longer range Wi-Fi capacity are growing, and so are the demands for new technology to support it.
Cheap and Dirty Wireless Remote Control
Column:
Open Communication
June 2017
Dealing with RF circuits is daunting for most experimenters. It is tricky and a bit frustrating if you build your own RF circuits. Now you don’t have to — thanks to the many available wireless modules.
Personal Radio Technologies
Column:
Open Communication
April 2017
Cell phones aren’t the only option for communication with your family and friends.
Spectrum Shortage Threatens the Future of Wireless
Column:
Open Communication
December 2016
With the grown of wireless technologies, spectrum usage demand is on the rise. The problem is, there’s only so much spectrum to be had.
What’s in the Works for Wireless?
Column:
Open Communication
October 2016
Wireless is so ubiquitous these days, we take it for granted. However, there are even more things to expect for/from it in the future.
Virtual Instruments Improve Electronic Experimentation
Column:
Open Communication
August 2016
Virtual Instruments: How to get a bench full of test equipment for only a few hundred dollars.
How Wireless Signals Propagate
Column:
Open Communication
June 2016
Learn how different types of radio wave signals propagate. It may not be quite as simple as you think.
So, You Think You Know Wi-Fi
Column:
Open Communication
April 2016
Wi-Fi is just about the most widely used wireless technology in the world. However, there is a lot you may not know about Wi-Fi. Here is a primer to bring you up to date.
The Internet of Things. Who Needs It?
Column:
Open Communication
February 2016
Now that most of the affluent world is connected to the Internet, why not connect everything else?
Which Way Does Current Really Flow?
July 2002
Do we even know which way current flows? And, in fact, does it actually matter which direction current flows? Let's clear all of this up.
EMI/RFI: The Bane of Wireless
Column:
Open Communication
November 2015
Practically every electronic device is both an interference generator and susceptible to interference. Here’s a brief introduction to this natural phenomenon and how to minimize it.
The New Electronics Experimenter
January 2004
Electronics as a hobby is not going away as some have thought, it has just changed — BIG TIME!
Getting Back into Ham Radio — Trials and Tribulations
Column:
Open Communication
September 2015
Equipment choice can be harder than you think — especially when you can’t install antennas.
Smartwatches Need Communications Too
Column:
Open Communication
July 2015
The new Apple Watch acts as a peripheral device to your smartphone by utilizing multiple wireless links between the two devices.
Serial I/O Data Interfaces: Part 2
Column:
Open Communication
May 2015
Get familiar with the high speed gigabit serial interfaces that dominate I/O today since we all use at least one of these regularly.
New Short-Range Wireless Standards Target IoT Applications
Column:
Open Communication
March 2015
Now, it is easier than ever to connect devices over the Internet with the features available in upgraded versions of Bluetooth and ZigBee.
Serial I/O Data Interfaces: Part 1
Column:
Open Communication
January 2015
Data is transferred serially in most applications. However, there is definitely more than one way to “send” that cat.
Video Monitoring Over the Internet
Column:
Open Communication
November 2014
Video has gotten so good and cheap lately, everyone seems to be using it. One growing trend in this area has been video monitoring or surveillance, and with the Internet of Things movement, what used to be expensive and tricky is now common place and affordable.
White Space Wireless Ready for New Services
Column:
Open Communication
August 2014
It is no secret that we are running out of spectrum space for certain new and/or improved wireless services. One potential solution for this can be found in the white space spectrum.
The Internet of Things and Machine-to-Machine Communications Emerge as Internet Drivers
Column:
Open Communication
June 2014
In case you haven’t heard, the Internet of Things (IoT) and Machine-to-Machine (M2M) are the next big things in Internet growth and new communications applications. Both technologies are expected to enable billions of new devices in the coming years.
Software-Defined Radios Everywhere.
Column:
Open Communication
April 2014
Virtually all radios today — cell phones and Wi-Fi WLAN, for example — are software-defined radios. Find out exactly what SDRs are and how they work.
DSL and Cable TV Broadband Internet Access: How Do They Work?
Column:
Open Communication
February 2014
Chances are you’re already using at least one of these technologies, but recent upgrades have made them faster. Read about the technical details of each system and the most recent new features and specifications.
Wireless Watches Will Win the Wearable Wars
Column:
Open Communication
December 2013
Even though cell phones have encroached on the time-keeping arena, you may want to rethink the wristwatch concept.
10 Things You Need to Know About Wi-Fi
Column:
Open Communication
October 2013
Discover facts about this familiar wireless technology that you may not already know.
Connected Cars Communicate
Column:
Open Communication
August 2013
Telematics is the wireless technology that connects your car to the outside world ... and it is hot! Here’s a summary of this emerging technology.
Making a Modern Radio
Column:
Open Communication
June 2013
Take a look at how digital techniques have changed and improved analog radios.
60 GHz Wireless Transports HDTV
Column:
Open Communication
April 2013
Transmitting uncompressed digital high definition television signals is no easy task. Learn about the technologies that are currently being used to accomplish these transmissions.
LTE — The Wireless Cell Phone Radio Technology
Column:
Open Communication
February 2013
The motivation to develop LTE comes from the explosion of data services now available on cell phones that are stressing current infrastructures.
White Space Spectrum Benefits All Wireless Applications
Column:
Open Communication
December 2012
Spectrum, of course, is the electromagnetic radio spectrum that all of our wireless devices occupy. This free space spectrum is allocated by governments to the various radio/TV broadcast and wireless services to avoid interference and conflicts between users. After years of wireless progress and growth, there is precious little spectrum left for further development.
Near Field Communications
Column:
Open Communication
October 2012
What do we mean by "short?" For cellular, short may be a mile or so. For Wi- Fi, short means less than 300 feet. Bluetooth and ZigBee are even shorter with a maximum range of about 30 feet.
M2M —Machine-to-Machine Communications
Column:
Open Communication
August 2012
M2M is essentially automatic communications between two “things.” An example is a vending machine sending data to a remote computer indicating that it needs refilling and the money box needs emptying.
Open Communication
Column:
Open Communication
June 2012
What is 4G Wireless? 3G/4G ... Does it really matter?
Open Communication
Column:
Open Communication
April 2012
How to get your ham license.
Open Communication
Column:
Open Communication
February 2012
Comm Kits — A radio kit is a great way to get familiar with electronics and communications.
Open Communication
Column:
Open Communication
December 2011
Building a crystal radio — is it a sane thing to do?
Open Communication
Column:
Open Communication
October 2011
Whatever happened to CB radio?
Open Communication
Column:
Open Communication
August 2011
Bluetooth: Forgotten Wireless Technology or Just Taken for Granted?
Open Communication
Column:
Open Communication
June 2011
New Communications Device: The Tablet Computer.
Open Communication
Column:
Open Communication
April 2011
The wireless frequency spectrum crisis.
Open Communication
Column:
Open Communication
February 2011
New Versions of the 555 Timer IC.
Open Communication
Column:
Open Communication
December 2010
Update On the Mobile Wireless Products We All Crave.
Q & A about Digital Radio
Column:
Open Communication
October 2010
Crystal radios are just a simple diode demodulator for amplitude modulation (AM) signals. Typically, crystal radios are built to receive local AM broadcast stations. And while those stations still exist, that might not be the case in the future.
Crystal Clock Oscillators: The Heart of All Communications Products
Column:
Open Communication
August 2010
If you look inside any electronic product today, there are a few circuits and components that are common to all of them. For example, every product contains at least one microcontroller that runs it. Another circuit that you will see — especially in communications products — is a crystal oscillator or clock. This circuit generates precise timing signals that control everything else — including that microcontroller. In communications gear like radios, that crystal is the source of the exact opera
Experimenting with Commercial Wireless Modules
Column:
Open Communication
June 2010
Wireless everything. That is what I am seeing more and more. Practically every electronic product these days has some kind of wireless component or function to it. That’s why it makes sense to learn more about wireless.
Shortwave Listening: What it is, how to do it, and what to buy.
Column:
Open Communication
April 2010
Once the vacuum tube came along, radio really took off and stations sprung up around the world. Even with a simple radio, you could hear local and far away stations.Today, there are still many of us who like to do this. The activity is shortwave listening (SWL) and it is both fun and a challenge.
What’s New in Home Networking?
Column:
Open Communication
February 2010
Home networking with wireless and wired technologies.
New Integrated Circuits Make Wireless Easier
Column:
Open Communication
December 2009
The one thing that has made wireless so easy to implement everywhere is the integrated circuit. The single chip radio transceiver is a common device and it is available in many forms to give us the huge number of communications options we have today.
E-Books
Column:
Open Communication
October 2009
E-books offer one more way to communicate electronically.
How To Achieve One Gigabit Per Second Data Rate Over Wireless
Column:
Open Communication
August 2009
Longer distances, interference, and other environmental issues usually prevent that, but what we get is typically enough. With the new 802.11n standard, Wi-Fi speeds will be going up as more of the access points adopt the multiple input multiple output (MIMO) technology that will make 100+ Mbps common.
Smart Phones Leading Cellular Growth
Column:
Open Communication
June 2009
The cell phone has become a must-have item in our modern life. You pick it up when you grab your car keys and wallet or purse every day.
Wireless Made Easy with a New Kit
Column:
Open Communication
April 2009
Think of your TV remote control, garage door opener, remote keyless entry on your car, and other wireless devices you use daily. Now you can bring that convenience and functionality to other projects.
Converting To Digital TV
Column:
Open Communication
February 2009
Fun with converter boxes and antennas.
A Femto in your Future?
Column:
Open Communication
March 2008
What the devil is a Femto? I suppose it had to happen sooner or later. With indoor cell phone usage as poor as it often is, it was inevitable that someone would come along to solve that problem. And here it is — the femto cell. It just could be one of the next big electronic purchases you make.
Wi-Fi Makes Internet Radio Wireless
Column:
Open Communication
April 2008
One more option for the radio enthusiast: You just don’t know how lucky you are. Just think of all the options you have in listening to radio. There are the old standbys like AM and FM stations that most of us still listen to mainly in the car. There are thousands of stations nationwide and dozens in your local area. Then there is the newer HD radio that puts digital broadcasts into the AM and FM bands for higher fidelity, better noise, and fading immunity, and more station choices...
The 700 MHz Spectrum
Column:
Open Communication
June 2008
If it weren’t for spectrum, there would be no wireless. The good news is that spectrum does exist. The bad news is that there is a finite amount of it. Spectrum is sort-of like real estate. There is only so much land on earth so it too is finite. When you use it all up, then what do you do?
Ten Things You May Not Know About Bluetooth
Column:
Open Communication
August 2008
Bluetooth is a very familiar name these days if you have a cell phone or laptop. It is a wireless technology that has been around a while and probably can be credited as the start of a whole boat load of short-range wireless technologies. But even if you have heard the name, you may not really know all about it. Here are 10 facts that will update your knowledge of this hot wireless method...
The Software-Defind Radio Is Real
Column:
Open Communication
October 2008
Reading Hardware for Software Makes for the Ultimate in Versatility
Six Things You Should Know About Wireless
Column:
Open Communication
December 2008
Wireless started changing the world just after it was invented by guys like Marconi, Tesla, and others in the late 19th and early 20th centuries. And that change is still going on. Here are a few wireless developments maybe you didn’t know about.
OPEN COMMUNICATION
Column:
Open Communication
June 2004
Despite the fact that spread spectrum (SS) technology is very widely used in every day wireless applications, few people — including technical types — actually know how it or its CDMA derivative works. It is one of the more complex wireless methods, but it has some really great benefits. With over 70% of US cell phones using this method, chances are you use a CDMA cell phone. Here is an introduction to this killer wireless technology.
Open Communication
Column:
Open Communication
August 2004
We seem to be on a path leading to a totally wireless electronic lifestyle. The progress has been continual over the years, thanks to semiconductor technology and other advancements. More recently, there has been a flurry of announcements that make wireless everything possible. ZigBee is an important aspect of this.
OPEN COMMUNICATION
Column:
Open Communication
October 2004
In my August column, I wrote about the new ZigBee wireless system. In this issue, I want to complete the coverage of the various short range wireless options available today.
Back to the Bands
Column:
Open Communication
December 2004
A weekend project to return to amateur radio with kits — it doesn’t get any better than this.
Back To The Bands - Part 2
Column:
Open Communication
February 2005
Refer back to the December issue for all of the details. In this article, I will describe my experience with the QRP30 transmitter and the QAMP30 optional power amplifier.
The Magic of Antennas
Column:
Open Communication
April 2005
If you really want to know what makes any wireless application work, it's the antenna. Here, we'll summarize some of the most common types and make you aware of what an antenna really is and how it works.
Radio Frequency Identification (RFID)
Column:
Open Communication
June 2005
Wireless technology comes in all shapes and sizes these days. Radio Frequency Identification or RFID is one of them. You have probably seen the initials RFID and didn’t really know what they meant. Yet, you may already be using it.
A Radio That Thinks
Column:
Open Communication
August 2005
An Introductory Look at Software-Defined/Cognitive Radio
Wireless Mesh Networks
Column:
Open Communication
October 2005
Today, what computer is not networked? If it is not connected to the Internet via a dial-up, broadband cable, or DSL modem, it is connected to a local area network (LAN), which, in turn, is connected to one or more other networks. And, LANs are not restricted to offices — they are also in many homes.
Internet Telephones
Column:
Open Communication
December 2005
By now, you have all probably heard of Internet telephones, or IP phones as they are sometimes called. They are also known as voice over Internet protocol or VoIP phones. In fact, you may already have one if you are one of those early adopters of high tech stuff. If you don’t have one, you can almost be sure that a VoIP phone is in your future. Let’s take a look at how these phones work.
Short-Range Wireless Explosion
Column:
Open Communication
February 2006
Wireless everything. If it seems like you are hearing and seeing more about wireless devices every day, it’s not just your imagination. Over the past few years, there has been a virtual explosion of new wireless devices and services.
Short-Range Networking
Column:
Open Communication
April 2006
Most of us think of long-range communications when we think of communications applications. Long-range is subject to interpretation, but is usually many meters to many miles. Short-range communications is typically 10 meters or less. We use short-range wireless devices virtually every day; some examples being our infrared remote controls, remote keyless auto entry, garage door openers, Bluetooth headsets on cell phones, and wireless thermometers. But short-range wired communications are...
TV On A Cell Phone
Column:
Open Communication
June 2006
I suppose it had to happen. You can do almost everything else with a cell phone these days like play music, take digital photos, send and receive text messages and emails, play games, and even surf the Internet. Why not TV?
Testing HD Radio
Column:
Open Communication
August 2006
Back in the April ‘04 issue of NUTS & VOLTS, I introduced some of you to digital radio broadcasting. It was mostly a theoretical discussion because there were few stations on the air and even fewer radios available. But today, digital radio — now called HD Radio — is actually here.
The Ultimate Wireless Hobbyist
Column:
Open Communication
October 2006
Wireless has been a hobby for well over 100 years. And looking back, I have actually been a wireless hobbyist for most of my natural life. I have tried almost all aspects of this hobby and have witnessed an amazing evolution along the way...
OFDM - Orthogonal Frequency Division Multiplexing
Column:
Open Communication
December 2006
Have you heard of orthogonal frequency division multiplexing (OFDM) yet? If not, your knowledge of communications techniques is definitely lagging behind the real world. Here is a quick look to bring you up-to-date on thiswireless technology that is being adopted across the board in most new communications and networking systems...
Tesla Invented Radio, Not Marconi!
Column:
Open Communication
February 2007
Make sure your history is correct and give proper credit where credit is due.
MIMO 101: Next Generation Wireless Technology is Finding Its Way Into Most New Systems
Column:
Open Communication
April 2007
In case you haven’t heard, MIMO means Multiple Input Multiple Output which — by itself — still does not explain very much. It is a relatively new wireless technique that makes use of two or more transmitters, receivers, and antennas to greatly improve...
Fiber Optics — The Invisible Communications Network You Use Every Day
Column:
Open Communication
June 2007
The world has been rewired many times over the decades. Telegraph and telephone wiring came first. Then electrical power. (Yes, electrical power wiring actually came after the telegraph and telephone wiring. Doesn’t seem right does it?) ...
Cell Phones — 10 Pounds of Technology in a 5 oz Package
Column:
Open Communication
August 2007
No other electronic product incorporates as much of the latest technology as a cell phone, and especially in such a small package...
HD Radio In Your Future?
Column:
Open Communication
October 2007
I just finished testing Radiosophy’s new HD100 digital radio and was impressed enough to want to tell you about it. In case you are still in the dark about this radio technology, HD radio is the digital radio service that...
How Far Can You Go?
Column:
Open Communication
December 2007
With the number of wireless standards, products, and applications increasing almost hourly, it is a rare day in which any of us will go without some wireless usage.
