Cibola
Search and Rescue

Less Basic Communications

by Tom Russo

This article originally appeared in Volume 7, Issue 11 of Lost... and Found.

There have been several articles in these pages about communications. Mike Dugger wrote an article in January of 1998 entitled "Basic Radio Communications," in which he discussed what to look for in a radio if you wanted to buy one, and a bit about how to talk on one when you bought it. I wrote another in May of 2001 about how to behave on the radio, a little about how to use one, and how to communicate more effectively. But in looking over the articles it seems to me that there's a gap in the minilessons. We have never really had one about what to do in the months after you've passed your Ham license exam to make yourself a more effective communicator.

I have this piece of paper that says I'm a ham. Now what do I do?

It is a common cliche to say that your ham license is "a license to learn," but its being a hackneyed phrase doesn't make it a false one. Your license gives you the privilege of running a transmitter, but it's up to you to acquire knowlege and experience that makes you a communications asset.

Obviously, one of your steps is going to be that you need to purchase a radio and get on the air.

If you can afford it, buy a mobile radio for your car as well as the handheld you keep for missions. Handheld radios perform poorly inside vehicles, as the metal shell of the vehicle interferes with the propagation of radio waves, and the antennas used on handhelds are notoriously inefficient. If you can't afford a separate radio to mount in your vehicle, consider purchasing a docking booster amplifier that you can use with your handheld. A docking booster amplifier will allow you to power your radio from your car's electrical system, boost its signal, and allow you to connect it to an external antenna on your vehicle. When you get where you're going you can always undock the radio and replace its regular antenna and battery pack for portable operation. You will also need a compatible speaker-mike for your radio if you go this route. If you're dead set against spending much more than the price of your handheld, you should at the very least get a handheld radio that can take an external power adapter (many can't), a magnetic mount antenna and a speaker-mike --- you can then plug the radio into your cigarette lighter, plug in the antenna and speaker-mike, and have something that will work better than a handheld, if not as well as a mobile rig.

The point of having a radio in your vehicle is to allow you to use all that dead time while you're driving about your everyday business to get in the habit of talking on the radio, and to listen to how these things get used. Try to monitor all the time, especially when enroute to trainings and missions. My own mobile rig is always on if I'm in my vehicle, although you can never quite be sure what frequency I'm monitoring. I try to monitor whatever repeater is nearest to me at any given time, and typically announce that I'm doing it by saying "KM5VY Mobile, monitoring" when I come on frequency.

Simplex vs. Repeater operation

There are two basic ways by which Hams communicate by voice on 2 meter FM radio. These are called "simplex" and "repeater" operation. Let's start with simplex.

In simplex operation two or more operators communicate via direct station-to-station contact. In this manner of operation communications occurs along direct line-of-sight paths. In most cases, when we're using 155.160 in the public service band we're using this method. The advantage of simplex operation is that it requires no infrastructure --- you simply agree on a frequency with all the parties, and as long as you're within range you can communicate. The disadvantage, of course, is that line-of-sight limitation. If there's a big honkin' rock in between you and the other station (e.g. one of you is in Albuquerque and the other is in Cedar Crest) you will most likely not be able to carry on the contact.

In repeater operation there is a station called a "repeater" --- usually located on a mountain top or high tower --- that monitors one frequency and retransmits everything it hears on another. Communications is still "line of sight", but the important lines are between the various parties and the repeater site, not the direct lines between each party. Most repeaters run with fairly high power, much higher than you would normally output on a handheld, and even higher than your mobile rig; this buys you a lot of range as your 5 watt handheld's signal down at 5000 feet is boosted to 100 or more watts by the repeater up at 10,000 feet.

In the US, the input and output frequencies of 2 meter repeaters are usually 600KHz apart. Whether the shift is up or down depends on what part of the band the output frequency is in. When you see repeaters listed you'll usually see them as the repeater's output frequency with the offset direction specified as a plus or minus sign, for example "146.900(-)," indicating an input frequency of 146.300 and an output frequency of 146.900. Most ham transceivers sold in the US know about the standard pattern of repeater offsets and the band plan that specifies where repeaters tend to be, and if you tune them to a frequency in the range where repeaters usually are then the offset will be set automatically. This is not always the case, so know your radio and how to use it. I'm sure none of my readers are the sort who consider user's manuals to be part of the packing material to be thrown away as soon as possible, so I'll leave it at that.

Another common feature of repeater operation is the use of "PL" or "CTCSS" tones. PL is a trademarked term owned by Motorola, and stands for "Private Line." CTCSS is the generic term and stands for "Continuous Tone Coded Squelch System." They refer to the same thing: the transmitter must include a sub-audible tone of the appropriate frequency or the receiver will not open squelch. Most repeaters use CTCSS tones to deal with interference problems --- if they're located in a fairly noisy area and didn't use CTCSS then noise could key the repeater. You'll often see repeaters listed this way: "146.900(-, 67Hz tone)" indicating that the repeater uses a negative offset and requires your transmitter to include a 67Hz subaudible tone in order to be heard. If you tune to a repeater that requires a tone but do not set your radio to use the tone then you'll never hear the repeater keying up when you transmit, and nobody will ever hear your transmission unless they just happen to be in simplex range of you and are listening on the repeaters input frequency instead of its output frequency. Some old transceivers do not have CTCSS encode/decode capability, and if you're thinking you might save some bucks by buying an old boatanchor you should look carefully for this feature lest you be unable to use most area repeaters.

Antenna considerations

In both types of operation the quality of your antenna will influence the ease with which you can make contacts, but clearly simplex operation is even more demanding. With repeater operation your signal is amplified dramatically from a high point at the top of a mountain, whereas with simplex you're relying on your relatively weak signal propagating directly to the other station. Handheld "rubber duck" antennas are an inefficient "compromise" antenna that can be replaced by a number of more effective options; some team members have replaced their rubber-duck antennas with quarter-wave whips, others have telescoping whip antennas, and some of us carry "roll-up" J-pole antennas made out of twin lead transmission line normally used with television antennas.

Common simplex frequences

Generally speaking, frequencies in the ranges 146.40-146.68 and 147.42-147.57 are reserved for FM voice simplex operation under the ARRL's band plan. The band plan does not have the force of law, but "good operating practices" --- which are required by law --- typically include observing the established band plans.

An important frequency to know is 146.52MHz, the "National Simplex Calling Frequency." This is a frequency that is set aside for simplex operation, and you can use it to find hams to talk to. Ideally you should not use the calling frequency for extended contacts, but rather use the calling frequency as a way of finding a station to talk to, then agree on a different frequency to use for your contact. You should definitely program your radio to include 146.52 as one of its saved frequencies, and you should try to monitor it whenever you're aimlessly tuning around the band.

Again, although the ARRL band plan does not have the force of law, the FCC Special Counsel for Amateur Radio Enforcement just recently wrote to several hams advising them not to use 146.52MHz for extended contacts, because doing so was not "good operating practice" --- he later rescinded his finger-wagging, but the point is that you can't go wrong if use it only to establish a contact and then move to a mutually agreeable alternate frequency.

Other useful simplex frequencies are 147.42, 147.45, and 147.51MHz. These are good frequencies to switch to after you've established contact on 146.52. I keep all three programmed in my handhelds. Before we received our license for 155.265 we used to use 147.42 on trainings a lot.

Useful repeaters in the Albuquerque area

There are a lot of them. A great resource for repeater maps of the state is the Upper Rio FM Society website, www.urfmsi.org. That said, here are some of the more common Albuquerque area repeaters you should know and program into your radios:

Frequency(offset,tone)Location
146.900(-, 67Hz)Southeast Albuquerque with wide area coverage
146.940(-,100Hz)Mount Taylor, La Mosca
147.100(+)Rio Rancho
146.720(-,100Hz (or no tone with reduced sensitivity))Raven Road/S.14
146.960(-,100Hz)Capilla Peak, Manzanos

All of these repeaters get used on missions with some frequency, you should get to know them and make sure you're set to use them before you head out to a mission. If you get in the habit of using your radio often you'll soon get to know the areas where each of these repeaters is best.

There are lots more, but I don't want to make that table too big right now.

Avenues for further study

There's a lot more to being a ham radio operator than yakking on 2 meter FM in your down time. Consider exploring deeper.

Join the ARRL (American Radio Relay League). You'll get a monthly publication called "QST" that has reviews of equipment, projects to build, contests to enter, and plenty of other material to further your knowledge of the hobby.

If you like to read first and play later, think about buying a copy of the ARRL Handbook for Radio Communications. This is an annual publication, but most of the material is pretty timeless. It has in-depth expositions of much of the theory of radio and electronics, plus a large number of projects you can build yourself. Armed with the Handbook, you'll be able to understand why all those answers you memorized for the Technician exam were correct. In fact, I studied for the General, Advanced and Extra exams using just the question pools and the Handbook.

You can learn a lot more about antennas from ARRL publications. The "ARRL Antenna Book" is a huge tome with lots of theory and do-it-yourself projects just like the Handbook. There are many other antenna books you can buy from the ARRL. Go browse the ARRL website (http://www.arrl.org/) and see what tickles your fancy.

If you would like to get a more advanced view of how amateur radio fits into the general emergency communications picture, consider taking the ARRL Emergency Communications Continuing Education and Certification course. This is an on-line course consisting of about 20 lessons. The course costs $45 if you're an ARRL member ($75 if you're not), is self-paced, and runs for about 8 weeks. It takes about 25 hours to complete all the lessons, which involve activities to be shared with your "mentor" and multiple choice review questions. I found the course quite enlightening, and I recommend it to anyone who wants to kick their ham hobby up a notch. To learn more about the course and how to register for it, see http://www.arrl.org/cce/.

Upgrading is always a good thing to do. Your Technician class license gives you all the privileges that you need on a SAR mission, but the things you need to learn to get the higher licenses will only help you. The general class license is not that much more difficult than the Technician, but you do need to learn Morse Code --- what you get other than a deeper understanding of the hobby is access to HF bands for worldwide communications. Not much help on a SAR mission, but could definitely be useful in larger-scale disaster communications, and it's a heck of a lot of fun otherwise.

Nets

Get familiar with the various nets that are held on local repeaters. Every Thursday night at 8:30pm on all the Upper Rio FM society and Mega Link repeaters (that includes 146.90, 146.94 and 146.96) there is a "New Mexico Swapnet." This is a great opportunity to find used equipment, often at a bargain price. Tune in every week if you can. If you really get into it you can even volunteer to be one of the swapnet operators; I did that for about a year until I got too busy on Thursday evenings.

The Bernalillo Amateur Radio Emergency Services (ARES) net meets every Thursday evening at 7:00pm on 146.90, 146.94 and 146.96 repeaters. Try and listen in each week, and consider getting involved even if just to check in to the net and say you have "no traffic." It's a friendly group crossed with a fairly formal net, and a good way to see how things work when a net control station coordinates a frequency for clean, accurate transfer of information.

Lastly, there are several "social" nets held on the various repeaters in the area. The "SCAT" net (Senior Citizens And Travellers) meets every morning at 7:06AM on the Sandia Crest repeater (145.33(+, 100Hz)) for general chit-chat and friendliness. "Rusty's Raiders Net" meets every morning from 8:45-10:45 on the 146.94 and 146.96 repeaters. Both are friendly groups.

Radio Games

Do not underestimate the value of hobbiest activities in advancing the skill and knowledge you can bring to bear on your SAR activities.

A fun activity that will bring together your interest in radio, map-and-compass skills, and physical fitness is Amateur Radio Direction Finding. In this sport you use radios with directional antennas and other equipment you can build yourself, combined with your ability to navigate using a map and compass to find hidden transmitters. Both foot and car activities are held in the Albuquerque area. It is much harder than it sounds --- it's really easy to get distracted from your land navigation tasks when you start bushwacking because you think you're a hundred yards from a transmitter! There are monthly competitions, usually in the Oak Flat Open Space area --- see http://home.att.net/~wb8wfk/ for details.

There are many other opportunities to explore how to use amateur radio more effectively. Everything you do to expand your knowledge and skill as a radio operator has the potential to make you more of an asset to SAR. I hope this article and others I've got planned for future issues help inspire you to pursue these opportunities.

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