Index

A Brief Introduction to Amateur Radio

Amateur Radio is an exciting and fun avocation!

So, you've heard about Amateur Radio, sometimes

called "ham" radio, and you're curious. Maybe you

know something about it from a friend or relative,

but you're really not sure what it's all about. This is

hopefully a useful introduction to Amateur Radio

that tells you not just what Amateur Radio operators

do, but also tells you why they do it, and gives you

some idea of the history behind this avocation.

From my perspective, there are three great traditions in Amateur Radio.Almost all Amateurs participate

to some extent in all three of these traditional activities, and all three can provide enormous personal

satisfaction and growth in the hobby. Each of these traditions goes back to the roots of Amateur Radio

history, even as far back as Marconi himself.

Traffic Handling Tradition

The original motivation for the formation of the American Radio Relay League (ARRL), the national

non-profit organization that represents the interests of Radio Amateurs in the United States, was

traffic handling. In the 1900's and 1910's, the state of the art long and medium wave radio equipment

and antenna designs were capable of interstate communications, but not yet capable of transcontinental

communications. Radio Amateurs organized their efforts into "nets," where they would meet at specified

times on well-known frequencies to exchange "traffic" or radio messages intended for delivery in distant

locations. Through these cooperative, volunteer efforts, messages could be delivered from one coast

to the other in a matter of hours rather than weeks, at essentially no cost to the users of the system, who

were usually friends or neighbors of the Radio Amateurs involved. While this National Traffic System

exists even to this day, few people know about it, because the national communications infrastructure

of postal mail, telephone, and now the Internet has evolved and become convenient, affordable, and

(somewhat) reliable.

But the tradition of traffic handling lives on. To the traffic handler,

it is the content of the communications that is most important.

Making sure that the information gets through and is accurately

relayed and efficiently handled is the most important thing.

Today, many Radio Amateurs are active in public service and

emergency communications organizations. The Amateur

Radio Emergency Service (ARES) is a nationwide organization

dedicated to providing communications in the event of natural

disaster or in civil emergency situations where existing data

and voice networks are either inoperative or insufficient.

When Hurricane Andrew devastated the Miami, Florida area in

August, 1992, and left a quarter million people homeless, some

of the first communications out of the disaster area was carried on Amateur Radio. When tornadoes struck

the central Texas towns of Jarrell and Leander in May, 1997, the Williamson County ARES provided the

only communications in and out of Jarrell for several hours, and provided much-needed supplemental

communications for disaster relief organizations such as the American Red Cross for days afterward.

When Iraq invaded and occupied Kuwait in the summer of 1990, a lone Kuwaiti Radio Amateur was able

to stay on the air during the entire occupation, smuggling information about the plight of his people to the

outside world using reliable data passing forms of radio teletype (RTTY). When disaster strikes, Amateur

Radio is many times the only means of communication.

Most day to day Amateur Radio communications is not so serious as natural disasters or civil emergencies, of course. The traffic handling tradition lives on in the simple act of passing the time of day with someone on the radio. It lives on in those Amateurs who build and establish repeater stations, which can enable users with small handheld radios to extend their effective range and reliability of communications. It lives on in those who provide free communications to public service events like marathons or bike races or parades. Learning how to make radios and power supplies that are reliable and ready, and how to choose and effectively use the appropriate radio frequencies for the needs at hand is important. The traffic handling tradition develops Radio Amateurs who can engage in reliable communications, be it a simple conversation, or civil emergency traffic.

The DX Tradition

Since the invention of radio communications by Gugliemo Marconi in 1894, Radio Amateurs have always been interested in extending the envelope of the radio communications state of the art. From the very beginning, Amateurs have been interested in seeing how far away they could contact other stations. Marconi himself set numerous distance records in the early days of radio, constantly improving the transmit range and reception capabilities of his equipment. Today, Amateur Radio operators routinely use High Frequencies (HF) to communicate with stations around the globe. They even use Very High Frequencies (VHF) and Ultra High Frequencies (UHF) to establish contact with other stations by using the moon to reflect their signals!

Amateur Radio operators work hard to build

great stations for working DX!

The term DX comes from an abbreviation for "distance" that

has been used by Morse code operators for over a century.

A DXer is someone who seeks out contact with stations in distant

or exotic places. The original DXers, like all other Radio Amateurs,

used the Morse code to communicate. They know that because

the Morse code requires only a narrow bandwidth, it can maintain

signal integrity over longer distances than any other mode of

transmission. In many cases, the use of Morse code instead of

voice or data transmissions can be the difference between being

able to establish contact or not being able to at all! Many other

factors can also contribute, including propagation conditions, antenna

type and direction, radio design and much more. DXers are known

for giving the extra effort to improve their chances of "working" that next DX station.

To the DXer, it is not the nature or content of the communications that is really important; it is the ability to establish two-way communications in the first place that is important. Many of these contacts are made under extreme difficulty or in adverse conditions that try the Amateur's ability and equipment to the utmost. Maybe it's a station 1,500 miles away that can be contacted on 432MHz only because a weather front is "ducting" the signals back to earth instead of out to space. Maybe it's a rare Caribbean station on 50MHz that can only be worked when sporadic clouds of ionization in the atmosphere develop in just the right place and time. Maybe it's a shortwave contact from Texas with a small expedition on an Antarctic island in the south Atlantic Ocean. Maybe it's working another station via "moonbounce" or knowing when the "long path" on the HF bands might be "open."

Even with the best antennas, distant stations can be weak.

In many ways, DXers help push the state of the art in understanding

how radio signals propagate. Amateur Radio operators have studied

the relationship between the sun and shortwave propagation for

decades. Amateurs were among the first to attempt "moonbounce"

and "meteor scatter" communications. Amateurs even discovered

certain forms of "transequatorial" propagation of VHF frequencies

that are still not very well understood. DXers have provided enormous

contributions to the general body of knowledge on antennas, antenna

modelling in software, receiver design, using digital signal processing,

and many other aspects of radio communications necessary to effectively

chase DX.

Many DXers especially like to collect QSL cards from other Amateurs. These cards are a way of extending written confirmation to another Amateur Radio operator about a particular radio contact. Ask a DXer to show you their QSL card collection sometime, and you may be pleasantly surprised to see cards from all over the world - from exotic islands, to remote desert lands, arctic regions, places you've read about and maybe imagined visiting some day. DXing is a fun and challenging way to experience the world.

The Experimenters Tradition

The very first Radio Amateurs had to build all of their own equipment. While

that is no longer the case, quite a few delight in the ability to build hardware,

write software, modify gear, and otherwise experiment with radio equipment.

The Amateur Radio Service is, in fact, the only personal communications

service in the country where licensed operators are allowed (and even

encouraged) to modify, build, and otherwise experiment with their own hardware!

Most Amateurs no longer face the need to build their own equipment, as many

commercial companies sell equipment designed specifically for the Amateur

bands. But that doesn't mean that there isn't plenty of opportunity to design,

build, and modify! It doesn't even need to be radios themselves. Many builders

start out learning how to solder connectors on coaxial cable, or how to assemble

a new antenna. Kits are availble to build many station accessories, such as switch

boxes, interface cable, electronic Morse code keyers, amplifiers, test equipment,

and attenuators.

Building a radio or station accessory from a kit can be a very rewarding experience. Kits and designs range from the very simple to complete to much more complex projects. Most have been designed by fellow Radio Amateurs and many offer features not available from any other source. In addition to kits prepared with components and instructions, there is a wide variety of published plans for building all sorts of things. In fact, there are whole books on the subject! Many hams also modify existing radio equipment for use on the Amateur bands. This can be as simple as changing a crystal or adding an audio output connector or as complex as replacing whole sections of a radio with newer design componentry. Almost every Radio Amateur at some point has dabbled in building or modifying equipment.

Assembling an antenna for world-wide HF communications

One area where Amateur Radio operators are well known for experimenting

and building is antenna design. It seems like almost every issue of the popular

Amateur Radio magazines feature articles about new antenna designs or

construction techniques. Many Amateur Radio operators have also

experimented with modelling antennas using their computers. This involves

complex software that predicts an antenna design's performance in the real

world. Amateurs are constantly improving our understanding of both antenna

design theory and practical computer modelling of antennas.

Digital communications are another area where extensive Amateur Radio experimentation is taking place. Digital communications over the air extends all the way back to the introduction of radio teletype (RTTY), but today includes a wide variety of protocols and encoding schemes. There are literally dozens of digital modes in daily use on the Amateur bands - many of which were pioneered by Amateur Radio operators who sought to improve the state of the art. Interested in Spread Spectrum? Interested in Digital Signal Processing? Want to build or join a wireless network of computers? One that includes stations around the globe? Many hams are experimenting with these and other digital techniques that can enhance communications.

The Amateur Radio experimenter is a builder who loves radio and loves to make things work. While "plug and play" may be fine for some activities, the radio experimenter really enjoys the challenge and excitement of building or modifying or trying out new ideas.

An Avocation for Everyone

As you can see, the Amateur Radio Service encourages a wide range of

interests and activities. The above three traditions, which I believe

represent the heritage of Amateur Radio over the years, are by no means

mutually exclusive or even entirely representative. One activity that crosses

the traditional boundaries is radiosport contesting. Radiosport contesting

challenges participants to establish two-way contact with as many different

stations in as many different locations as possible in a given time period,

and reliably exchange certain information with them. Succesful contesters

draw from the traffic handling tradition that emphasizes reliable, efficient

communications, and the DXing tradition that emphasizes the desire to

contact many different places. Contesting can be quite competitive, quite

fun, and certainly a challenge to the skills of the radio operator. Many other

activities in Amateur Radio draw upon and help develop a mixed radio

operations skill set.

Amateur Radio is a gateway into a new and exciting world. It is an avocation you can follow the rest of your life and continue to find something new and interesting to do. It doesn't take a large investment to get started, and just because some Amateurs talk with their friends in Singapore or Argentina on a regular basis, or spend their entire weekend contesting, or are always building things that never seem to work just right, doesn't mean that that has to be the kind of Amateur Radio you take an interest in. There's plenty of room for everyone, and plenty of activities to choose from. You may even find that your interests change as you explore new terrain in the world of radio. But that's just another part of what makes Amateur Radio so rewarding...

DE WM5R

University of Texas Amateur Radio Club N5XU

Send comments to: utarc@www.utexas.edu

Last updated: 17 October 2006