Friday, October 07, 2005

SHTF Radio

Let's Talk Radio Turkey at Parallax Adjustment has inspired me to write my own thoughts on the subject of emergency (or SHTF) communications. The ability to communicate will be (and has been) a very important aspect of SHTF preparations. There are lots of hams who are more experienced and more knowledgeable on these topics than I, and if you are a ham, most of what I'm going to say won't be news to you. If you are interested in ham radio, this is going to give you lots of things to think about. I'm not saying that everything here is gospel, I just want to present some ideas that can be food for thought. Of course, these are all my opinions and some others might think I'm full of it. Even if you are not a ham, but are, shall we say, interested in SHTF scenarios, maybe this will get you interested in ham radio.

Among the many failures of the mainstream media, there is the almost non-existent reporting of the activities of ham operators during widespread emergencies. Many hams take part in the hobby primarily to stay well-practiced and prepared for emergency communications when they are needed. When floods and storms take down phone communications, hams are on the job passing messages, known as "traffic," from station to station, town to town, and state to state, providing information for friends, families, and sometimes even official agencies. In many areas, hams who are also weather-watchers take part in Skywarn, which coordinates with the local NOAA station to provide on-the-spot weather reports, providing valuable real-time information regarding lightning activity, heavy rainfall, indications of tornados forming, and various other severe-weather phenomena.

My interest in ham radio began with two things: the ability to carry on digital communications over radio, and the ability to provide emergency communications. I wasn't really into ragchewing (just talking with other people), or DX chasing (trying to contact stations in other countries). Although I have done both of those as well. These are just a collection of my thoughts and opinions about equipment that should be considered when preparing yourself for SHTF communications involving amateur radio.

Pardon me if I accidentally slip into some ham jargon that non-hams may not understand. I'll try to catch myself and explain any odd terms as they come up.

Handheld VHF/UHF Radio
Everyone should have, at minimum, a VHF (2-meter) handheld. A dual-band VHF/UHF radio is even better. These are the handgun equivalent of ham radio: there are bigger radios that will work better when they are available, but the handheld is the one you can always have on you and have access to immediately. Every licensed person in your family should have one (at least). Also, if you are going to get more than one, get them all in the same model so that everyone knows how to work it, and if something happens to one, no one has to go through a learning curve to operate a different one. Having everyone on the same model also assures that all the power packs are interchangeable, and only one model of charger needs to be used to charge all the packs. Make sure to get a model for which you can also get aftermarket battery packs that will allow the radio to operate from regular "AA" or "AAA" cells, so when the manufacturer's power pack goes dead, you can operate from plain old batteries if you don't have the time or ability to recharge the pack. As soon as you get your handheld, rig up a power cord that will allow you to plug in to your vehicle's (or generator's) power so that you can run it without having to use batteries whenever possible.

Mobile VHF/UHF Radio
These rigs will operate the same frequencies and bands as your handheld, but--generally--be able to transmit with about 10 times as much power. Every vehicle you plan on trying to move should have one. As with the handheld, a VHF rig will do fine, but a dual-band rig is even better. Again, go for the same model in each vehicle so no one has to learn to operate a bunch of different radios. Believe me, with all the bells and whistles and curious combinations of buttons that must be pressed on some radios, this is important. For that matter, avoid as many bells and whistles as possible and get radios that are simple and intuitive to operate.

HF Radio
Avoid the extremely big and expensive do-everything rigs and get a smaller, portable model produced for mobile operations. They will work just as well as the big rigs at your home station, and when you need to move, you can unhook it and carry it out the door. Even if you don't want to operate mobile all the time, install the mounting hardware, coax, power lines and antenna mount on your vehicle anyway. That way when you need to move, you can just bolt the radio in place and go. Keep the mounting bolts/screws that you need in your vehicle all the time so they'll be there when you need them. Every couple of weeks, or whenever, hook it up and make sure it all still works. An automobile is a very inhospitable environment for coax and electric wires. Eventually, the coax will develop an invisible break, a connector will get water in it, or your ground system will fail. It's much better for you to find a failure while sitting in your driveway playing around than when you actually need to communicate.

What They're For
Your handheld is very useful for close-range communications, such as car-to-car or building-to-building. If you are in an area where repeaters are still operational and within range, the range of your handheld will be greatly increased. A "repeater" is a radio system that receives your handheld's much weaker signal and re-transmits it at increased power with an antenna that is much more efficient and usually much higher up than your handheld.

The VHF/UHF mobile rig has essentially the same use as a handheld, except that it has more power and can be permanently set up with a much better antenna than the rubber duck on your handheld. Some models of dual-band rigs can also be set up to function as an emergency repeater--another important consideration. Such "cross-band" repeaters will require users to be using dual-band handhelds to take full advantage of.

The HF rig is generally for long-distance communications. Varying by frequency and time of day (not to mention solar conditions), it can be used to communicate across your state, across the country, or around the world.

Your handheld will come with a rubber duck antenna already, which is fine for most situations. But if you are in a more stationary position, there's nothing to prevent you from connecting your little handheld to real antenna, which will greatly increase its effectiveness.

There are hundreds of different models and variations of antennas for your dual-band mobile rig. Many hams sneer at magnetic mount antennas because they "look bad" or something. Forget about them and get a mag-mount anyway. If you end up in a place that has a metal roof, or anything tall and metal, for that matter, you can always connect up some extra coax and slap that mag-mount as high up as possible. A mag-mount on the roof of a house will work better than on the roof of a car. The higher you can get any antenna, the better it will work. I know of one very effective portable station that was set up by putting a mag-mount on top of a metal filing cabinet.

You should have an antenna, or a collection of antennas, that will allow you to operate your HF radio while moving. We call this, understandably, a mobile antenna. In the interest of a SHTF situation, I would recommend against anything extravagant like a screwdriver antenna, or even a bugcatcher. (Disclaimer time: I have a bugcatcher and would love to also have a screwdriver, but that's just me). Just get a few single-band antennas like the Hamstick (and yes, I also have a couple of Hamsticks stored in the toolbox of my truck). You must always be aware that--especially in rough conditions--eventually something will stop working correctly. A simple antenna like the Hamstick is very hardy and almost impossible to break. If something does happen to one of them, you will still have a few others that will get you on the air, although perhaps on a different set of frequencies. If your multi-band screwdriver antenna goes bad, that means you lose communications on...multi-bands.

Don't concentrate exclusively on mobile/portable operations. What if a disaster has knocked power out, but you are still able to remain at home? Have a system of antennas at your home location--whatever you have space for or allowed to erect under building restrictions (better yet, don't live anywhere that would put some dumb restrictions on your antenna experiments). Chasing DX is a lot of fun, and you might want to build or buy an excellent DX antenna, but for SHTF purposes, it won't be enough. (Second disclaimer time: I absolutely love my GAP Titan DX).

Simply put, the antenna made for DX, or long-distance (worldwide) communications, is designed so that it emits power at a very low angle of radiation. By emitting at a very low angle, the signal can go as far as possible before bouncing off the ionosphere and coming back down as far away around the world as possible. But if you need to communicate with someone in the next couple of adjacent counties, your bad-ass skyhook is going to be shooting its energy right over their heads and they won't hear a thing. This is why I recommend something like the Near Vertical Incident Skywave, or NVIS antenna. The NVIS is designed so that it emits radiation almost straight up, so that the signals bounce off the ionosphere right over your immediate area and come down all around you. A NVIS antenna will allow you to communicate very effectively on the lower HF bands out to a couple hundred miles or so. A NVIS antenna can be easily erected with 20-30 feet of pvc pipe, some wire, rope, and tent stakes.

Other Stuff
As I said before, eventually something will fail. Carry extra coax cable, heavy-gauge insulated wire for power lines, connectors, and lighter-gauge wire for making antennas. Cheap insulated speaker wire is excellent for making dipoles on the fly. When erecting field antennas, you will need insulators. Remember that anything non-conductive can be an insulator. I like to use pvc couplers and elbows. Plastic drink bottles can be cut up and turned into several emergency insulators. You will also probably want rope. Pack a slingshot or a bow with some fishing line to shoot over tree limbs or whatever else you can find to tie an antenna to. You can then use the fishing line to hoist your rope/wire up into the air. I prefer a very light-draw child's recurve bow for this. My compound hunting bow tends to shoot the arrows too far. Or just tie the line to something and throw it, if you are accurate enough with your throwing (I'm not).

I have found a butane-powered soldering iron to be an indispensible tool. The ability to solder antennas without having to rely on an electric soldering gun/iron is just wonderful. You can also take the tip off and use it to start fires, if necessary.

Carry an antenna book. It could be something as huge and encyclopedic as The ARRL Antenna Handbook if you really want it, but for these purposes something smaller and more practical is probably a good idea, like Simple and Fun Antennas for Hams (also available from ARRL). Any antenna books focusing on "field day" antennas will be very useful.

Rope. Did I mention rope? Something that won't start disintegrating when exposed to daily UV radiation, if possible.

Get a tuner that also has an SWR meter in it so you can make sure your homebrewed field antennas are working right.

Many models of VHF handhelds and mobile rigs can also receive the FM broadcast band. You may want to consider this in your purchase of these radios. They will also be useful as public service scanners, unless you are in an area that uses a trunked system. In that case, you'll want a dedicated scanner that is designed to monitor such systems. Likewise, remember that your HF radio is also a general coverage shortwave receiver, and can receive the AM broadcast band as well. CB radios have their place. They are cheap and plentiful, and there should be at least one in your radio arsenal. Plenty of non-hams will be trying to use these, and if you are near a major highway, you can learn a lot about traffic conditions by listening to truckers. However, also be aware that your HF radio can be used to monitor CB frequencies, although it is actually illegal to use it to transmit on such frequencies.

Make sure your portable power supply, be it generator or automobile, is properly filtered. When you do need to communicate, it is important to also be able to hear other stations, and not just a several-megahertz-wide swath of noise.

Like I said in the beginning, this isn't gospel. I'm not saying you absolutely must have everything mentioned here. I just hope it might give some prospective or new hams some ideas about what can be done.

I'm sure I've forgotten a few things in here that I had wanted to mention, so if I think of anything else I'll update it.

And remember, the main goal of most hams is to have fun.

UPDATE: CW (Morse Code)
I knew I had forgotten something. Non-hams know it as Morse Code. Hams call it CW, for Continuous Wave. You should learn it and use it. Many people will say that it's obsolete, but in this time of multi-mode digital radio communications, so is the human voice. It is true that there are other ways of communicating and even transferring files over radio. It is also true that in almost all cases, you will need a computer to operate in these modes, and you may not be able to take a computer and other necessary peripherals when the S hits the F. (Plus, a computer is going to be another enormous drain on your emergency power). When conditions are so poor that your voice can't be heard, CW can still get through. Pack a simple straight key with your SHTF radio gear. A straight key is unlikely to break because of its simple design, and if it does, repairs are easy to improvise. For that matter, it's fairly easy to improvise a straight key of some sort from scratch. I still have a plain no-frills straight key that came with a Heathkit code practice oscillator. I screwed the key down to a piece of 1x4 for a base, and it has served me well for many years. Currently the minimum requirement is to be able to copy code at 5 words per minute to be licensed for HF frequencies. Just learning the code will almost automatically put you at 5 wpm. After that, just get on the air and use it a couple of times a week, and your speed will naturally improve. And this opinion is from someone who almost never operates in anything but computer-assisted digital modes.

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