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| Worldwide Communications Without The Monthly Bill! |
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You say you thought Captain Kirk's communicator was the coolest thing since mushrooms on your pizza? You wish you yourself could talk to people all over the world without having to pay for Internet access? You want to do it from your picnic spot in the local park but don't want to pay a monthly bill for a cell phone? What you need is an amateur radio license, along with some basic equipment for HF amateur radio - then you can do all of this even when the phones aren't working and you're miles from the nearest cell site. The entry level license in ham radio - Technician Class - initially doesn't grant any privileges on the worldwide HF bands, but by learning Morse Code well enough to copy it at 5 WPM (words per minute), you open a whole new world of operating privileges, because then you can operate in CW (code) mode on several of the HF bands, and you get voice privileges on part of the popular 10 meter band as well. Pass an additional written test as well, and you can upgrade to a General Class license, which grant you significant operating privileges on all of the HF bands (including full amateur privileges on several of them). The Technician license with credit for passing the 5 WPM code test is the bare minimum needed, but once you get the General the door to worldwide communications by radio is basically wide open to you. (Note: As this website was being put together, the WARC conferences had just changed the international treaty that required potential amateur licensees to demonstrate Morse proficiency in order to obtain HF privileges. This requirement is now up to the individual administration in the potential licensee's country. Here in the U.S. the FCC might well drop Element 1 from the testing requirements eventually - several petitions for such a rule change have already been filed - so check the current licensing requirements in case I haven't had time to update this page yet!) This page will overview some of the most popular activities on HF amateur radio. I can't cover everything, of course, because the licensed ham can operate in a wide variety of operating modes too numerous to cover in any significant detail here, but I can give you a cross-section of the most popular activities, and will proceed to do just that right now. |
| AM/FM/SSB On HF |
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Now that you're all confused by the alphabet soup, AM (amplitude modulation), FM (frequency modulation) and SSB (single sideband, shortened from single sideband supressed carrier AM) are the three voice operating modes authorized to amateur radio operators on the HF bands. If you can speak, you have the primary prerequisite for operating in any of these three modes, which have one thing in common, namely that you use a radio to transmit the sound of your voice over the air. The vast majority of amateur radio communications these days is in SSB. Fortunately, then, and not surprisingly, modern HF rigs are designed to make the most efficient use of this mode. SSB, for technical reasons that I won't dwell on here, yields the best range of the three voice operating modes. If you want to operate voice and talk the maximum distance your station is capable of, SSB is definitely the way to go. AM, from which SSB is derived, used to be the primary voice operating mode in ham radio. It is still the primary operating mode in VHF aviation radio. However, its range is less than SSB, and it takes up more bandwidth on the air. Some hams refer to it as Ancient Modulation. Nevertheless, many modern rigs retain the capability to transmit in AM (usually at lower power levels than when operating in SSB), and older AM rigs can still be found on the used market if you really want to experience the audio quality on a good, clean AM signal...and there are still many diehard AM operators active on the air for you to talk to if you choose to go this route. FM is the most widely used voice mode on the VHF/UHF bands, but on HF is permitted only in a portion of the 10 meter band. Above 29 mHz there is an FM sub-band where hams operate FM via repeaters and on simplex, and although FM does not offer as great a range as SSB, many modern rigs include this mode and many hams enjoy using it. If your rig has FM, try sitting on 29.600 which is the 10 meter FM simplex calling frequency, and see what you can hear and "work" when the band is open. Many hams enjoy this mode because it is much quieter than AM/SSB operation. I often keep my mobile HF rig parked on 29.600 FM, so feel free to give me a holler if the band's open. |
| Digital Modes: Continuous Wave (CW) |
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CW (continuous wave) operation is the oldest mode known to amateur radio. It existed before any other operating mode was invented and is still in use today. Many hams operate exclusively in CW. The primary prerequisite to operating in this mode, obviously, is the ability to send and receive Morse code. A CW signal occupies a much narrower bandwidth than any voice signal and frequently will be heard when a voice signal will not get through, which sometimes happens when the bands are very noisy, or very crowded, or both. This mode also lends itself well to operating low-powered portable equipment, because technical requirements for generating a good CW signal require a lot less circuitry and power than what is needed to generate a good voice signal. For all of these reasons, CW is the primary operating mode of choice for QRP operators, which are hams who operate very low powered transmitters, usually 5 watts or less. Before you dismiss the idea of worldwide communications with less than five watts of transmitter power, consider this. When Admiral Byrd made his initial expeditions to the south pole, his primary means of contact with the rest of the world was by radio with an amateur radio operator in Brooklyn, New York, operating in the CW mode. This ham was operating out of a small apartment using a transmitter designed around what are commonly known as "peanut tubes" and having a maximum power output of about 1/4-watt. That's right, 250 milliwatts to work from Brooklyn to the south pole. That's over 9000 miles! When the band is open, 5 watts CW is often more than enough power. Furthermore, when the bands are NOT open, the maximum legal 1500 watts PEP probably won't get through anyway. At any rate, CW is a digital mode. The telegraph key simply turns the transmitter on (digital logic state 1) and off (digital logic state zero), which is about as simple as it gets! |
| Other Digital Modes |
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Beyond CW, there is a wide variety of other digital (non-voice) modes that hams on the HF bands are authorized to use. Today, most of these are practiced using a computer and a sound card in conjunction with the radio in order to conduct communications. Although they are too numerous to mention them all, let's look at some of the most popular of these modes. One of the newer modes that has gained popularity at a phenomenal rate is PSK31. This mode involves using a computer keyboard to type the message, which is sent over the radio and then appears onscreen at the receiving end. The PSK31 signal uses a narrower bandwidth by far than even a CW signal. Once you learn how to tune a PSK31 signal with your computer and radio (it's easy: park the radio on the right frequency, start the software, point and click with your mouse), you'll find that you can often get 100% copy on a PSK31 signal that your ears can't even detect from the speaker! Another popular mode is SSTV (slow-scan television), which transmits a digital (non-moving) picture. SSTV enthusiasts store these pictures in their computers and exchange pictures with their fellow SSTV operators. Hams with digital cameras can take pictures of their shacks, themselves and their families, or whatever else they want to send, store the pictures on their computers, and then send the pictures over the air. There are numerous other protocols (modes) for digital communications as well, but the basics are pretty much shared among all of them: computer, radio, sound card. Once you successfully mate the three for operating in any one of these modes, you're often ready to operate in most, if not all, of them - on a worldwide basis by HF ham radio. Hunt around on the web and you can usually even find some free software to experiment with the digital modes. |
| HF Operating Activities |
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Regardless of which mode or modes you choose to utilize, there are a lot of different things you can do when you put the mode or modes of your choice to work on the air. The simplest and oldest of these is probably the good old fashioned "ragchew" where two or more hams get together on the air and go back and forth like neighbors chatting over the back yard fence. This may not seem so exciting until you consider that the hams you end up ragchewing with might be the ham down the block, or it might be someone on the other side of the planet! In fact, these days, most of the astronauts in space are also hams...so you might even find yourself chewing the rag with someone who isn't even anywhere on the planet, but is in orbit somewhere out in space! The object is to talk (or type, or exchange pictures, or whatever) and make friends and enjoy the hobby, period. You can of course QSL the hams you ragchew with and add the QSL cards to your collection if you're working toward an operating award such as DXCC. There is even an operating award to be had just for ragchewing, called RCC (Ragchewers' Club), sponsored by ARRL. Speaking of operating awards, this is another popular pursuit among hams - I call it The Great Wallpaper Chase, and I'm not really one who tries to collect operating awards, but many of the awards like DXCC and such can be quite a challenge to qualify for and quite an achievement to capture. Many hams start out operating casually, collecting the odd QSL card here and there as they go along, until one day ten or fifteen years down the road they pull out all the cards they've collected and check, and realize they only need six more countries for DXCC, and suddenly The Great Wallpaper Chase is on as they try to work those six additional countries for this very prestigious award. Another popular award is Worked All States - which requires at least one confirmed contact with a station in each of the fifty states in the United States. This one is so popular that there are even nets held every night where hams check in and are available to be contacted by hams who need a contact in that state. I'm aware of at least one such net (Century Club Nets) that operates its own QSL bureaus and issues its own awards on the side for things like contacting a certain number of portable or mobile stations, contacts with club officers, and other such acvhievements made while working towards Worked All States. Contesting is another popular activity enjoyed by many hams. There are countless contests for operators to participate in, each seemingly with its own objective. Some are sponsored by ARRL, or by CQ Magazine, or by local ham radio clubs. Some are worldwide while others are more limited in scope. The common thread is competing for the highest score, not only against other hams, but also against yourself in trying to beat your own personal best previous score for that particular contest. Still other contests have no one winner but seek to reach a particular objective, such as November Sweepstakes in which the object is to work stations in each of the many ARRL sections in the US and Canada, or the annual Field Day in which the "contest" is secondary to the fact that the event is one of two annual disaster preparedness exercises sponsored by ARRL (the SET exercise every October is the other). |
| So...How Hard Is It To Make Contacts? |
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The above question has been asked of me by people working toward upgrading from Technician to General. Most hams who are Technician licensees know there's a world of difference (literally as well as figuratively) between throwing your call out on a 2m repeater in order to make a contact, as opposed to busting a pileup on HF to work a DX station on another continent. Folks at first seem to expect making contacts on HF with hams hundreds or even thousands of miles away to be really difficult. And, to be sure, it can be, especially if band conditions are poor, or the DX is a really rare prefix with dozens of hams in the pileup running big power in an effort to work a new rare DXCC entity. For new operators, however, it's not as hard as you might expect. Working a new country, for example, is easy, because you're new...you have so far worked nobody...you need everybody...and no matter who your first contact is, it'll give you a new DXCC entity (your first!). One down, 299 to go........... My first HF QSO was with a mobile station in one of the New England states. I was running the ARATS club station at the time, operating a 100 watt Yaesu FT-990 into a delta-loop antenna strung between two 50-foot towers. Solid, armchair copy on both ends and we chatted for about ten minutes as his wife drove the car down the interstate while he operated with his Alinco mobile HF rig sitting in his lap. It was my first DX contact that really opened my eyes to what's possible on the HF ham bands. At the time, my equipment consisted of a borrowed 10m mobile rig and a magnet-mount CB antenna that I'd bought at a yard sale! Driving down a local thoroughfare, tuning the radio while stopped at traffic lights, I eventually heard a station on an island off the coast of Scotland working a pileup and left the radio on that frequency, listening to learn how hams conducted themselves in such situations so that I'd know how to do it right when I started actively seeking DX contacts myself. It wasn't hard to figure out: wait for the DX station to go, "QRZ?" and transmit your callsign, and when the DX station repeats your callsign back to you, you go ahead and exchange signal reports. Piece of cake, except that the DX station was in Europe and I was in Tonawanda, NY with a mobile rig that MIGHT put out 25 watts PEP on a good day. This guy had a pileup going that sounded like it included some guys running serious power. Fun to listen to and learn from, but I really didn't think I could actually work the guy. This fellow was a good DX operator, though...and so eventually, he said, "Are there any mobile stations out there who want to get a contact...any mobiles, please come now..." and gave his callsign. Suddenly the frequency fell silent, for everyone was doing what you're supposed to do: listen to the DX station. The DX wanted to work mobiles. I wasn't hearing any. Apparently he wasn't either, for he repeated, "I'll try once more, any mobile stations wishing to contact me please go now" and repeated his callsign again. I was just about to pass beneath an overpass where the road I was driving on passed under an interstate. Picking up my microphone, I transmitted my callsign - actually from under the bridge! - thinking to myself that I might as well have been talking into my coffee mug. "Great, I've got 25 watts, or maybe less, and a lousy antenna under a @#$%&* bridge to try and contact a guy who's gotta be a couple thousand miles away." Not knowing why I was even bothering, I transmitted my callsign, setting the mike back down on the seat just as my car emerged from under the bridge. A few moments later I had my first DX contact. I had to pull over and sit in a parking lot for a few minutes - not only to scribble down the time, frequency, callsign and signal reports for my log, but also (mainly, in fact) to calm down so I didn't wreck the car because I was experiencing a major adrenaline rush! So, that's how hard it is to make contacts: it's not. If the band is open, you can literally work the world, with far less than the maximum legal amount of power and even with less than ideal equipment (even from under a bridge). Period. Of course, if the band's not open, I don't care how much power you have, unless the station is in your ground wave they are not going to hear you. Period. Fortunately, we have several bands to choose from, and usually one or more bands is open at any given time, so you can usually find a place to work DX if you know a little about propagation so you're not trying to work Europe on 160 meters in the middle of a hot July afternoon (when 15 meters is probably wide open, but D-layer absorption virtually guarantees that you'll be wasting your time on 160). |
| Try Before You Buy? |
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Still not convinced? Okay, then perhaps it's time for me to talk a little more about Field Day. It's an international event these days, as DX stations are encouraged to participate and submit logs - this wasn't always the case but over the past few years the rules have changed. Field Day first got started back in the 1930's as a disaster preparedness exercise. It's still a disaster preparedness exercise at its heart. The object, primarily, is for ham radio clubs, emergency communications groups, non-club groups of hams banding together to work Field Day, and (beginning with 2003) Emergency Operations Centers used by ARES/RACES and similar groups to operate stations under simulated emergency conditions - meaning that stations are powered using batteries, generators, solar cells (anything but commercial mains) - preferably in a public place, such as a park, where the public can see us and wander over and ask what's going on and thereby give us the opportunity to sharpen our public relations skills while we're sharpening our emergency communications skills and our contesting skills. While we're sharpening everything, we try to contact as many other Field Day stations as possible. This goes on for an entire weekend - it's the last full weekend in June every year - from early Saturday morning until Sunday afternoon. Who wins? Everybody. Who loses? Only the people who stay home and don't bother to participate. And since the public is welcome, even if you aren't a ham you'll be welcome to show up at the Field Day site of the local ham radio club in your area and check out what's going on there, and see for yourself if you might be interested in getting on the air yourself. Now, beginning with 2002 there was incorporated into ARRL's rules for Field Day something called a GOTA station, which many clubs incorporate into their own Field Day plans as well. GOTA stands for Get On The Air and is a station set up at Field Day for operation by two groups of people: 1. Inactive hams - as a means of trying to get them re-interested in the hobby. 2. The Public - operating with licensed hams as control operators, allowing them to legally operate a ham station, hopefully getting them interested in the hobby. The point: Find your local club, visit their Field Day site, operate their GOTA station, and see for yourself just how easy it is to make contacts on HF. If this experience doesn't convince you that making HF contacts is not at all difficult, please consider seeking professional help. Spend an hour or so at the mike and you should at the end have produced a list of contacts all over the US and Canada and perhaps some DX as well. By then you'll probably also have made some new friends who are hams, and who will be happy to help you get your license - so get it, and I look forward to working you on the air! |
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| Debunking A Myth (Or Correcting A Common Misunderstanding) About SWR Readings And Coax Length |
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There is a commonly misunderstood fact about the relationship between a transmission line and the operating frequency that has been misstated to beat the band, until now it's to the point where I think there are more people misunderstanding this than there are people understanding it correctly. Even guys working at radio shops are getting this one wrong, so I think it's time to set the record straight once and for all. THE FALSEHOOD: Your coax should be exactly 1/4-wavelength at the resonant frequency of your antenna, otherwise you won't be able to get the proper match. This is what has been told to countless radio hobbyists. It is simply NOT TRUE. Here, then, are the facts: Common practice when checking the SWR on a station antenna has the operator unscrewing the coax from the back of the radio, screwing it into an SWR meter, and using a short jumper piece of coax to go from the meter to the rig. The operator then sits there in the shack and keys up the rig, adjusts the meter in the CAL position, then switches to REF and reads what he or she supposes is the correct SWR reading. What's the problem with that? Well, the problem with that is that in order to get the correct reading, the reading has to be taken AT THE ANTENNA, NOT IN THE SHACK SITTING NEXT TO THE RADIO! Okay, now that this is understood, we can move on to the issue of the length of your coax. THE TRUTH: A transmission line (coax) that is exactly a quarter wavelength (or even multiple thereof) at the operating frequency, will exactly "repeat" the impedance it sees at one end of the line at the other end. Meaning that IF - and ONLY if - your transmission line is a 1/4-wavelength (or multiple thereof) at your operating frequency, you CAN read the SWR at the "shack" end of the line and get the same reading you'd get if you climbed out on your roof, or up your tower, and took the reading at the antenna the way your supposed to do. This is the ONLY advantage to having a transmission line whose length is 1/4-wavelength long. It does not mean your antenna will have a higher SWR than if you used a random lemgth of coax. It does not mean your antenna won't work right if you use a random length of coax. It simply means that unless your coax is 1/4-wave, 1/2-wave, etc. you won't get a true SWR reading sitting in your shack with the meter - you'll have to go up to the antenna to get a truly accurate SWR reading. Note that SWR is not the exact science that many people seem to believe it to be. Having an SWR of 2:1 or even 3:1 at a given frequency is not necessarily the end of the world. That contact with the station off the coast of Scotland that I mentioned above was made with an SWR of just under 3:1 - yet I did, in fact, make the contact. I don't recommend running with an SWR that high all the time, of course. The point is that having a somewhat high SWR means your antenna system isn't at full efficiency and therefore not working as well as it could be - not that it won't work at all. Naturally, you want to work on it if your mismatch is that high, but it can probably wait until after you've made the contact! It is my sincere hope that this will help someone, somewhere avoid this all-too-common misunderstanding of the relationship between transmission line length and the wavelength of a signal at a given operating frequency. Now you can get it right, and if someone else tries to tell you differently, I'm sorry, but they're wrong - period. |
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| Photo at top of page shows a Kenwood TS-50 compact HF rig covering 160-10 meters, maximum 100 watts transmit, general coverage receive. I have one installed in my van for mobile HF operation...currently using 20m Hamstick antenna. |