Open with prayer
Thank you for choosing this presentation over the others you might be attending today. My intention is to give you a broad overview of ham radio, so I will be covering a lot of ground. I will be talking about some technical things, but my intention is not so much to teach you but rather to show how these concepts can be made clear for kids, and how there is a great deal of latitude for creativity. Also, in order to talk about some aspects of ham radio, we need to understand some concepts such as frequency and wavelength. I'll be assisted in this presentation by my daughter Sarah, who is also a licensed ham.
Let's begin with some definitions. What is ham radio? It is people using radio to communicate, to serve, to learn. In the US, the Federal Communications Commission licenses hams and sets the rules. They have identified five reasons why they see value in ham radio.
1. Recognition and enhancement of the value of the amateur service to the public as a voluntary noncommercial communication service, particularly with respect to providing emergency communications.
It is "amateur" radio, and hams are strictly forbidden from profiting from their use of the airwaves. In fact, since I am here as a paid speaker at this conference, I cannot actually demonstrate what I am talking about. Fortunately, Sarah can. The second part of that statement is important too, since most people associate ham radio with emergencies, and it continues to be an important part of what we do.
2. Continuation and extension of the amateur's proven ability to contribute to the advancement of the radio art.
I will be talking in just a moment about some of the history of ham radio and we will see that a large part of what makes radio useful to us was developed by hams. And there are still many hams who are actively involved in new inventions such as software radio, integration of radios and computers, and new antenna designs.
3. Encouragement and improvement of the amateur service through rules which provide for advancing skills in both the communication and technical phases of the art.
The FCC grants three different levels of license, and each requires a greater level of knowledge. The lowest level is called the Technician license, and requires knowledge of basic electronics, radiation exposure and safety, and operating procedure. Sarah holds a Technician license and has been granted the call sign KB9ZNC, which uniquely identifies her in the world as an American ham. The General license requires learning about the components that make up transmitters and receivers, and more about electronic circuits. You also need to pass a Morse Code receiving test. With the General license, you gain access to the radio frequencies that allow you to talk around the world. The Amateur Extra class is the highest level license. Extra class licensees have full access to all the frequencies the FCC has set aside for amateur use. They can also prepare and administer the exams by which hams upgrade their licenses. I hold an Amateur Extra class license, my call sign is AB9FH.
4. Expansion of the existing reservoir within the amateur radio service of trained operators, technicians, and electronic experts.
The FCC recognizes that the country needs to have a base of trained technicians who understand how communications works, who can support and repair our increasingly complex communications systems.
5. Continuation and extension of the amateur's unique ability to enhance international goodwill.
For myself, the idea of being able to sit at a desk and talk over the airwaves with someone on the other side of the world was one of the big appeals of ham radio. Many hams in other countries, such as Japan, have entered the hobby in part to help them learn English. It helps tremendously when hams in Florida and Texas monitor the airwaves and provide assistance to sailors who have lost power, or mobilize to provide medical care and humanitarian assistance when a family was attacked by pirates off the coast of central America.
So much for government work. How can God use amateur radio?
1.Service to one another
We're put here for good works, ordained long ago. Technology, operating skill .. these are not ends in and of themselves, as men think, but only good in God's eyes when put to use. I will talk about some of the operating activities hams are involved in, some of which are fun, many of which provide the opportunity to demonstrate skills and character, but I hope the focus stays on how they can be used to further the Kingdom of God. For myself, I firmly believe that a big part of the reason I became interested in ham radio was that God was motivating me.
The world sees your good works and gives glory to God,
and in that way we can preach the Gospel without using words. Amateur radio
operators cannot broadcast, except in some very specific circumstances,
and international contacts are required to avoid controversial topics.
Within the US, we need only avoid obscenity and commercial activity. There
are hams in Muslim countries, you need only conduct yourself like a local
missionary would, not bringing up the topic but able to answer questions
when posed. The Salvation Army has its own amateur radio network, called
SATERN. There are also individuals and organizations that train missionaries
in ham radio, and provide email and message services via ham radio to missionaries.
3.Help to general public in emergencies big and small
This is a more specific case of my first point, but I wanted to make the point that service includes more than just emergencies. Many hams make it a point to develop the ability to operate using battery or solar power, to be able to erect new antennas to replace those blown down in a storm, to be able to relocate to 911 centers, hospitals, shelters and provide communication for police and emergency management personnel.
4.Service to missionaries
Ham radio can provide worldwide communications using very little power and very simple antennas. New digital methods make it possible to provide email and file transfer.
5.Skills - talents are to be exercised, a skillful worker
Ham radio provides the opportunity to learn and exercise many skills. I will be talking about the variety of academic subjects that can be applied to ham radio. Ham radio licensees can build their own equipment, many operate using nothing else.
6. The Christian Soldier
What is to come has many concerned. We are called to use
the time we have, the talents we have, the resources we have, to be ready.
Knowledge of electronics, communications, networks, emergency procedures,
are likely to be useful. We will make sure our children learn what they
need to know in their school time. Better still when their, or our, hobby
time builds preparedness as well.
What are the skills, the subjects? How does ham radio relate to school?
The American Radio Relay League, the national organization of hams in the US, has prepared some materials to help us in this area. I have included a short list in the handout, but the website there has the entire list. Two pages cover 10 topics and grade levels from elementary to college. I won't just read the list, but as we cover other topics, I'll try to link them to items on this list.
I want to cover a little bit about the history of ham radio. This relates to one of the purposes we saw that the FCC sees in ham radio, the proven ability to contribute to the radio art.
Electricity had been wondered about and described starting with the Greeks, but it was not until the late 1800s we saw practical use made of it. Maxwell described the link between magnetism and electricity, and it was the application of his theories that made radio possible. Hertz demonstrated that creating sparks caused electromagnetic waves to travel through the air. Marconi was the first to patent an idea for using those radio waves to communicate.
As experimentation continued with radio waves and how they traveled, an observation was made. To discuss this we need to begin one of our technical discussions. We talk about electromagnetic waves, but what exactly are they? Light, heat and radio waves are all different forms of electromagnetic radiation. We can visualize them like a wave on the sea, or perhaps imagine holding a Slinky between two points and causing a wave to pass the length of it. We call them waves because the radiation acts like physical waves in many ways. If we could see the waves as they pass through the air, and if we could freeze one in time, we could measure the distance between one place where the radiation was at its peak value and the next peak. This distance is called the wavelength. If we started time again, and watched a particular point in space and counted how many peaks passed by it during one second, we would have measured the frequency of the radiation. Wavelength and frequency are inversely related; increase the wavelength and lower the frequency. Increase the frequency, lower the wavelength. Marconi was creating very long waves for his radio transmissions, wavelengths of over 100 meters. Back to the observation: the theories about radiation said that it travels in a straight line. Once you get far enough away from the transmitter for the curvature of the earth to be significant, the radio waves should be going over your head. But it was observed that this was not happening. As indicated in the top diagram, the waves seemed to be following the curvature of the earth. It was observed that, the longer the wavelength, the farther the wave would follow. At this point, most of the research began to focus on the longer wavelengths, and the shorter waves, 200 meters and less. we left to the "amateurs" to experiment with.
Observation number 2. It was noted that this ground wave phenomenon only occurred at long wavelengths. Someone transmitting at shorter wavelengths should not be capable of interfering with anyone else, certainly no one far away. But as the lower diagram shows, a puzzling thing was happening. Station A would transmit. Station B would not hear a thing. Station C would hear Station A loud and clear. Since B was quiet, this must not be ground wave. It didn't take long to deduce that the waves must be traveling in a straight line, but bouncing off something up above the earth. What was this mirror in the sky? In 1902 a scientist named Heaviside proposed that there was a layer of charged particles, called ions, up in the upper reaches of the atmosphere. This so-called Heaviside layer was theorized to be the mirror. This mirror had some strange properties though. It did not always work the same way, in fact some times it did not work at all. Our current theories, backed up by observations made by rockets passing through the atmosphere, suggest there are at times several layers of ions that change in height, strength, and number depending on the strength and angle of the sun, and also on the eruptions of storms on the surface of the sun. Predicting the results of these layers is an important skill for the communicator who wants to use this mirror to extend the reach of his transmissions. There are numerous sites on the Internet dedicated to just this task. One other interesting phenomenon: if Station C is at sea, salt water acts as a mirror to radiation in a similar way. If our ionospheric mirror is at its highest, it will reflect our transmissions back to earth as far as 2000 miles away. If they bounce of f the ocean, back up to space and bounce again, that's 4000 miles. These mirrors work so well that it is a common practice to deliberately direct transmissions away from our intended target and let the radio waves take the long way around the earth instead of the short path, if the short path lies in the area of Station B.
I want to talk about modes, in other words the various methods of using radio waves to communicate. We need to make another technical digression here.
My example for this discussion is my non-conventional radio you see here. Well okay, it is a flashlight, but it's a radio too. It has a lightbulb that emits electromagnetic radiation in the form of light. It has a reflector and a lens that act like an antenna to direct this radiation in a controlled manner. This radio is just a transmitter. Fortunately, each one of you is equipped with a pair of receivers so we don't need to provide that.
Now I want to use my radio to communicate. I turn it on...what am I saying? "Here I am?" That's a useful message if I am lost and want to be found but I want to do more. What can I do to the radiation to make it convey information to other people?
One thing I can do is turn it on and off. If I control how long I shine, transmit I should say, now I am getting somewhere. If I transmit patterns of long and short, and we agree ahead of time that a certain pattern means the letter A and another pattern means Z, I can start spelling words with my radio. Sound familiar? Hams call this mode "continuous wave". Continuous wave? I keep interrupting it, how can it be called continuous? Let's look at the non-continuous waves to see why. By the way, if I make all my transmissions and interruptions the same size and group them together in patterns of 7 or 8, and I call it "1" when I'm transmitting and 0 when I'm not, what do I have? I'm using digital communication! Morse Code transmissions is one of the oldest forms of digital communication.
Okay, I've turned my light on and off. What else can I do with the light? What if I adjust how much power I feed to the bulb, or I make lens bigger or smaller in area. I can vary the strength of the light. The term scientists use for the strength of a wave is amplitude. If I modulate, that is to say change in a controlled fashion, the amplitude of a wave, I am performing Amplitude Modulation, better known as AM. Morse Code made it possible to send words, AM made it possible to send sounds, such as voices and music.
What else can I do with my light? What if I change the color of it? Our eyes interpret different frequencies of light as different colors, so if I change the color I am modulating the frequency. Now I'm talking about FM!
One more thing I can do is combine the on-off patterns of continuous wave with FM, and modulate not by turning the signal off and on but by switching between two frequencies. This is called FSK, or frequency Shift keying and is used extensively in modern digital modes. Ever listen to your phone when connected to a modem or fax machine? You will hear the sound waver between two or more tones; that's FSK in action.
Other modes include facsimile and TV. In these the components of the picture are represented by changes to the signal similar to what we've already discussed.
We've mentioned the FCC before. They are the goverment agency responsible for radio and TV in this country. There are similar agencies in most countries and international organizations as well. One of the things these organizations do is control who gets to use what part of the electromagnetic spectrum for what. Ranges of frequencies are called "bands" and are usually referred to in terms of wavelength. Hams will talk about the 10 meter band or the 2 meter band. Parts of the bands are reserved for certain uses. For instance, the lowest frequencies in most ham radio bands are reserved for Morse Code only. Also some entire bands are reserved for the higher licensees.
The UHF and VHF bands are primarily for local contacts, although repeaters, satellites and now the Internet are stretching their range. The HF bands are where the world-wide action is.
A repeater is a radio that listens on one frequency and transmits whatever it hears on another. Its antenna is usually located on a tall building or tower, and it transmits with greater power, so it greatly extends the range of a small radio. For instance, I was able to stand in my front yard in the north part of Milwaukee, and talk to a ham in Beloit. On occasion we can talk with hams in Michigan, Illinois or Indiana.
There are several ham radio satellites that act as repeaters from orbit. Using a satellite, a ham in Nova Scotia can talk with another in New Mexico. And the International Space Station has ham radio equipment on board.
Now lets turn to the activities that hams engage in. I'll start with the public service activities.
Parades, charity runs, sporting events like the Boston Marathon need communications to keep running and to deal with emergencies. For may, hams provide a free source of skilled volunteers. They will shadow key people, watch intersections, stay with the ambulance or the flat tire van. By connecting GPS receivers with radios, the floats in the Tournament of Roses parade and the cars in the Great Circus Train can be tracked as they move.
Emergency communications are what hams are known for. There are two organizations of hams who train and serve when tornados strike or ice brings the power lines down. The Amateur Radio Emergency Service, or ARES, is part of the ARRL ham organization. The Radio Amateur Citizen Emergency Service is sponsored by the Federal Emergency Management Agency. In Wisconsin, RACES and ARES are one and the same. The national Red Cross has a working relationship with ARES, so they know who to call when they need help. The Salvation Army has its own network of hams, called the Salvation Army Team Emergency Network, or SATERN. The National Weather Service depends on hams acting as severe weather spotters.
These days we’re thinking more about homeland security. In the Spring of 2000, the ARRL began to organize a series of online courses on Emergency Communication. Then came 9/11. In July of 2002, the Corporation for National and Community Service provided a grant to reimburse hams who successfully complete the first course in this series. You may not hear about it, but hams are making a serious and important contribution, usually at no cost to the taxpayer.
The national organization of hams is called the Amateur Radio Relay League, and the word relay in that title reflects one of the first purposes for which hams formed organizations, traffic handling. Traffic is just a term for the messages hams pass across the country. These can be messages about the health and welfare of people within a disaster area, for instance the names of those in Red Cross shelters, or damage reports, or requests for supplies needed by workers. They can be warm greetings and birthday wishes and congratulations. These messages are passed free of charge, using a network of local, regional and nationwide on air meetings called “nets”. These nets and the hams who make them work together form the National Traffic System. I would like to extend an invitation to all here to send a radiogram to a friend or family member in another state. Just stop by our table in the lobby by the fireplace. We will copy your message down on a form something like a telegram form, relay it to another ham who will in relay it to another until we get the message to a ham who can deliver it to your loved one by local phone call. Practice in message passing at events like this help keep the NTS active and ready for when more serious messages will need to be passed. What a novel way to send your Mothers Day greetings!
QRP is the Morse abbreviation for reduce power, and it is also the name given to radios using less than 10 watts of power, a fraction of the power of an ordinary light bulb. QRP operators like the simple equipment, they often enjoy operating away from home since radio, antenna and power supply, otherwise known as a battery, fit in a pocket. They enjoy the challenge of making contacts using the minimum necessary power. When conditions are right, even a 1w signal can travel around the world.
The most competitive of hams enjoy contests. Almost every weekend of the year there is a contest going on somewhere. Usually the object is to contact as many stations as possible, with extra credit given for contacting members of the sponsoring organization, or for contacts using Morse Code. Contest exchanges are often very short; no chit chat, little more than exchanging callsigns and location. Contest stations will have high power amplifiers and finely tuned antennas.
Another popular activity for hams is DX. DX is the Morse Code abbreviation for the word “distance”, and is used to refer to the practice of making contacts with people outside of ones own country. The ARRL and other ham organizations issues awards for making numbers of DX contacts. Many who pursue DX do so for the challenge of finding that rare country. Many also like to collect QSL cards, colorful cards that hams exchange as proof that a contact occurred.
One of the privileges hams enjoy is the right to build our own equipment, something that cell phone users can’t do. This is referred to as home brewing. No, I don’t like the title either. Some design and build their own radios as a test of skill, some assemble radios from kits to save money. New designs of radios and antennas come out every year. There is sophisticated computer software to model the performance of an electronic circuit or antenna before you build it.
The opposite of contesting is rag chewing, just spending some time talking with a friend or making new ones. These can be one on one, or roundtable discussions. I participate in such a discussion each day on my way to work. Some hams have scheduled chats with friends, going on for years. With ham radio these can be with friends from the same neighborhood or another continent. Hams will also put out a call to whoever is listening, calling “CQ”, meaning calling any station listening.
Once you have the license, what about a radio? Most hams have a handheld radio that works primarily for local contacts, though there are ways to talk worldwide on them as well. These radios cost between $100 and $400 new, less if used of course. A base station radio that will work on all the HF bands will cost $600 -$3000 new (if you simply have to have all the latest gadgets). A perfectly serviceable used radio can be found for $300 - $600. A simple QRP radio kit can cost $25, with everything you need and well written instructions. Plans are available in the library or on the Internet for free, if you can find the components yourself. Antennas are available in just about all shapes and sizes and prices, but many hams use simple wire antennas that cost less than $20 in parts.
How do you become a ham? Each of the license levels requires a written test, and the General license also requires a Morse Code receiving test. The license itself is free, lasts 10 years, and is renewable. Hams themselves prepare and administer the tests, and they are allowed to charge enough to recoup their expenses, which usually works out to $8 to $10. I found books to study in my local library, and other resources on the Internet. There are several websites that will give practice written tests based on the same pool of questions that the real tests use. I have included the urls below. Radio Shack carries study books, you can order them if they don’t have them in stock. The ARRL sells study materials on their website. Some ham radio clubs will offer classes from time to time. The club that Sarah and I belong to does so.
There are opportunities to experience Ham Radio. One of the best is Field Day. Field Day is a time when hams all over the country move to locations away from where they normally operate, set up antennas and radios, and try to make as many contacts in a 24 hour period as they can. It was conceived as a practice of emergency capability, but now the emphasis is more of a social event and a chance to demonstrate ham radio for the general public. In fact, starting with last year, clubs can set up a special station for the purpose of letting the public talk on the air, a "get on the air" station and get extra points. Field Day is always the last full weekend in June. I will be adding a link to this site with a list of Field Day sites in the Milwaukee area. This will be the 71st year for Field Day.
Twice a year, hams invite kids into their homes, their "ham shacks", on Kids Day. This is a relatively new event, and is not as common, but it is growing every year. It happens in January and June.
For the scouts, there is a special event called Jamboree On The Air. JOTA is an annual event in which Boy and Girl Scouts and Guides from all over the world speak to each other by means of Amateur (ham) Radio. Scouting experiences are exchanged and ideas are shared via radio waves. Since 1958 when the first Jamboree-on-the-Air was held, millions of Scouts have met each other through this event. Many contacts made during JOTA have resulted in pen pals and links between Scout troops that have lasted many years.
Check out the following links for more information.