Sunday, October 4, 2015

Intro to HAM Radio for the Prepper

Prepping is more than just about preparing for the end of the world.  If the world is ending, then what is there to prepare for?  Some people will tell you not to bother with technology because an EMP will take out all the electronics anyway.  What if the catastrophic event doesn’t involve an EMP?  My own philosophy includes things that may or may not be available to me after an event.  My self-training involves skills I may never use.  You can’t be prepared for every possible scenario, so you have to make your own decisions about the path you take.

In information security, we had a rather simple formula with rather complex permutations.  
1)  List all the possible problem scenarios.
2)  For each scenario listed in step one list the following
  a.  What is the likelihood of an occurrence
  b.  What is the consequence
3)  Based on a balance of the answers in step 2, prioritize your actions to prevent the events listed in step 1
Using a formula similar to this one, automobile crashes happen pretty often, so we do what we can to prevent human injury when it does happen.  Someone dropping a cinder block from an overpass doesn’t happen very often, so although the consequences could well be fatal, we still have moon roofs on many vehicles.

If you want to hide in a bunker until the heat is over, then emerge you should ask yourself what you are likely to emerge to.  If this is what you intend to do however, you will need a good receiver.  Some would say a shortwave receiver and if you go that route, make sure it has true single sideband (SSB) capability so you can listen to more than just the voice of Xyz-stan or the People’s Republic of Bananas to keep you informed of what is happening around you.  Without a radio receiver, you have no way of knowing when it is safe to emerge.  For better information, get a general coverage HAM radio receiver and perhaps a pocket Morse code reader.

For everyone else, I will assume there are others on your list of co-survivors.  This being the case, I am going to suggest that your need for two-way communications with people is roughly the same as the closeness of your relationship.  

Getting Started
After SHTF, there is not going to be any FCC bothering you, but if you plan to communicate during an emergency and after SHTF, you need to practice before hand.  The license required to communicate over the two most popular frequency bands for HT HAM radios is the entry level “Technician” license.  This requires a very simple test which focuses on what you can and cannot do with a Technician HAM radio license.  HAM radio equipment does not have some of the Consumer Product Safety Bureau’s safeguards, so real damage to the equipment can result from handling the radios without knowing what you are doing.  The potential damage becomes more dramatic and more expensive with the higher levels of license, but more on that later.  

Assuming you have decided on HAM radio for communications, you should consider getting the entire family licensed although, it might be good to get one person to go through the process to see if it is going to be a part of your preparations.  Study guides are available online and many are free.  Testing is around $15 and goes toward compensating the Volunteer Examiner (VE) expenses.  (Yes, the testers are volunteers and any licensed HAM can become a VE.  There is no charge for the license and it is good for ten years.  There is no testing for renewal of your license, you just get online and re-register.  Once you have a family member licensed, you might consider making license study a part of your family’s together time to get everyone up to speed.  The Technician license requires very little study.

The Handheld Transceiver
(Also known as an HT or sometimes Handy Talkie)
Your household is of paramount importance to you, so equipping everyone in the house with the means to communicate within your household ranks pretty high.  Whether you go with Japanese or Chinese radios is a matter of economics and personal preference.  I have heard many disparaging stories about cheap Chines HT radios.  Mine have been dropped from my motorcycle at freeway speeds, subjected to drenching rain storms and a host of other hazards to technology.  I have not found them to be any more susceptible to failure than the Japanese radios.  Japanese HT radios “feel” more solid, but cost as much as ten times as much as the Chinese.  There are a very many people who disagree with me on this, so it is up to the individual to make a call here on Japanese versus Chinese.

Better than stock antennas will be a great idea for the radios, but don’t toss the old antennas because they are going to come in very handy later.  I have some long, bendy antennas, magnetic mount antennas for use when in vehicles and even some roll-up antennas that can be hoisted into trees for more height.

I would standardize your household on one make and model if possible to ensure parts interchangeability and programming ease.  (With a PC programming cable and free software, you can get one radio set up the way you like and copy that configuration to the PC to be “dumped” to each of the other radios.  Whatever brand you select, a dual-band is a very good idea.  The two bands I would seek are 2 Meter and 70 centimeter.  (The bands refer to the approximate wavelength of the radio signals and you don’t really have to know a whole lot about that at this point.)

The reason for these two bands will become obvious later on.  One limitation to these bands is the signal will not bounce off the ionosphere, so when they reach the horizon, they just keep going in a straight line.  HT to HT distance is extremely variable, but don’t believe anyone who tells you that more than five miles can be relied upon for an HT on these two bands.  More Wattage might help punch through heavy trees or some buildings, but you are not going to see a big range improvement.

I have seen a teen with 4 Watt Chinese HT costing around $30, along with a home built antenna she put together from metal tape measures communicating via satellites in orbit.  This is all about line of sight and the higher the antennas are, the longer the line of sight.

The Chinese radios can typically be configured (illegally and I strongly caution against it unless and until SHTF) to transmit on HAM, MURS, Marine VHF, Commercial VHF and UHF, GMRS and FRS frequencies.  This means that post SHTF, your choice of frequencies opens up quite a bit.  Many will receive NOAA weather radio broadcasts as well as local commercial FM radio broadcasts.

The radios you choose should also have dual-watch capability.  This simply means that it will switch back and forth between two frequency presets very quickly and stop on either one if it hears a “valid” signal.  Different manufacturers have different ways of referring to the two “sides” of the dual-watch radio.  Some refer to the Variable Frequency Oscillator (VFO) as in VFO-A and VFO-B, while others will just call them side ‘A’ and side ‘B’

One potential use for this feature would be if you have neighbors with similar radio preparations, you can set aside one frequency programmed into memory as a “named channel” called “Group” for instance.  In addition, you might have another channel for members of your household to contact each other without having to bother the entire neighborhood.  This channel might be your family name.  By the way, there is enough bandwidth to assign every household a different channel and there are enough memories on most radios that you can program all the neighborhood radios exactly the same.  The Jones household would set VFO-A to “Group” and VFO-B to “Jones”.

Once you have some HT radios to play with, get online and look up HAM radio repeaters in your area.  This is where finding an “Elmer” or mentor can really save you some time.  There are probably repeaters within reach of you that are free for you to use.  These may be owned by individuals or HAM clubs in your area.  What a repeater does is gives you a very high antenna with sensitive receiver and a good transmitter.  The primary repeater in my town allows anyone within about a 20 mile radius of the center of our town to talk to anyone else within that radius.  

There is an article on my blog about repeaters.  For the moment we need to talk about “tone” operations.  The most frequently used are variously called Continuous Tone-Coded Squelch System (CTCSS) and Digitally Coded Squelch (DCS).  These codes are not audible to the end user, but your radio may need to encode a special tone in the outgoing transmission that tells a repeater that you are not just accidentally tuning your transmitter to the repeater’s frequency.  You can set your preset radio channels to either send or receive or both send and receive these tones.  CTCSS is the most common in HAM use, so you can assume that’s what I’m referring to here.

When a channel is configured to receive tones, this means that in addition to “hearing” carrier from a transmitter, your radio will need to detect the correct tone in order to enable the speaker.  This is what I meant above by a “valid” signal.  There are some good uses for configuring receive CTCSS, but if there is none configured on your HT it will still work just fine with any analog repeater.  The transmitted CTCSS is what must match the repeater in order to function.

Programming
All HT’s are difficult to program because there are few buttons, so each must perform many functions.  I would urge you to learn to program your chosen radios manually because you may need that ability at some point.

Most of your programming is going to be via computer and USB cable.  You’ll hear lots of people talking about how difficult one brand or another is to connect to the PC.  This has zero to do with the radio, but plenty to do with the fact that the radios (pretty much every brand) are expecting a type of serial interface not found on PC’s for the last fifteen years (called RS-232).  This means that the lump on the USB programming cable pretends to be an RS-232 on the radio side, while acting like a USB cable for the computer.  This requires special drivers for your operating system and there is where your problem lies.  There are a lot of Internet resources for getting these drivers working if you have trouble.

Other thoughts on the HT
The uses for HT radios go way beyond the obvious.

In a rural setting a long range intercom system could be useful.  An HT radio can be used in an alarm system.

Beginning Base Operations
The good news is our next step up doesn’t require a license upgrade.

Once your household communications is up and running, you will want to expand your circle of operations.  As long as your community has working repeaters, this shouldn’t be a problem for you.  As many have pointed out, the repeaters in operation are a potential weak point in a grid down situation.  As long as they are there and not congested, use them.

The reason I mentioned 2 Meter and 70 centimeter bands specifically is the proliferation of mobile dual-banders that support cross-band repeat.  A mobile radio is one designed to be mounted in a vehicle.  Mine is mounted in a simple box with external speaker and microphone bracket attached so it can be lifted right out of my truck for desktop use at events and at home.  Two great things about a mobile radio as opposed to an HT are power and antenna.  

Power for HT radios is almost always below 10 Watts, whereas mobile dual-banders will put out from 40Watts to 85Watts.  This power is less important than the antenna, but it still counts.  There is so much power loss in coax cable that using an HT at your home base connected to an outside antenna up on a pole will sometimes perform less than the stock antenna.  Also, as I mentioned above, those extra Watts can help to punch through trees and buildings.

I have a good antenna on my truck with a magnetic mount and have good performance with that setup.  When used at home, it is connected to a tower mounted antenna that is of a size that would be impractical on a vehicle.  Remember from above, antenna height increases your range, so the higher you can mount it, the better.  Dual-band antennas are not bulky enough to stand out in most cases, so the risk of someone spotting your antenna at this point would be minimal.

From this point forward in your explorations, nearly every HAM radio you see will require a power supply of 13.8Vdc.  In engineering terms, this is 12Volts.  Automotive alternators put out quite a bit over 12 volts, so the radios were designed with the preferred voltage of 13.8Vdc.  They run just fine on the 12Vdc from an automotive battery when the engine is shut off, so don’t let this throw you.  For the house, you will need a DC power source that will provide enough amperage to drive your radio.  (Check the specifications on your selected radio but the more Watts out, the more Watts you have to put in).

Now to the fun part.  When your family only had HT radios, everyone had to stay within a couple of miles of home or be out of touch.  Using the cross-band repeat function on your mobile radio in combination with an elevated antenna in your home, you can increase the range of the HT users to somewhere between a five and ten mile radius from your home.  In addition, you can now communicate with neighbors via their mobile radios (either direct or via cross-band) at ten to twenty miles.  If you have a larger community of friends, you may have to relay message traffic between households, but you can see how this can build quite a large area of operations.

In addition to increasing the range of the HT radios, I have found that when I am around the house or otherwise using the mobile radio's cross-band repeat function, I can turn the power on my HT down all the way to make the charge last longer and even use a tiny little two inch antenna that doesn’t get in my way as much as the whip antennas.

Going Whole Hog
I am only briefly describing the more advanced areas here.  To treat it right, requires many articles and the hobby begins branching more rapidly here into specialized areas.  Many areas could be used to advantage by a prepper depending on what an individual or group decides will work into their plans.

The next step in your radio preparations might be to make the leap into High Frequency (HF) operations.  In order to do much operating on these bands you’ll need to upgrade your license to General.  There is a little more learning here but much of it simply builds on what you already know from the Technician license.  I believe that as your preparations progress at least one person in your mutual assistance group be capable of HF operations.  Since one is none and two is one, you might want to have a couple of people up to speed before the hammer falls.

HF signals will actually bounce off some layers of the ionosphere and be absorbed by others depending on a lot of factors.  To get your signal over the horizon, this is what you must do.  To determine where your signal might once again come down to earth, you are talking about something like calculating a bank shot in a three dimensional pool game.  You can get really scientific about this or you can just get on the air.   Antennas can be elaborate or simple.  I have seen people with several thousand dollars “invested?” and others with some scraps of wire and all getting similar results.  You can’t purchase success in HF radio, and the best operators I have seen do it on the cheap.

Getting on the air before things go south on us is critical because there is a lot more to HF operations.  There is an etiquette without which, you will likely be ignored even after SHTF.

I am going to break down HF communications into two categories for the purposes of preppers.  Strategic and Tactical.

Strategic Communications
Knowing what is happening in other parts of the world are not going to impact you today or tomorrow, but over the long haul, you still want to know.  In HAM speak, we call long distance communications DX.  This type of contact requires some skill (for transmitting), but you can certainly tune through the bands and listen.

Tactical Communications
For tactical planning and operations, you need to know what is happening within a few hundred miles of your location.

The antenna setup for DX communications above is slightly different than the one you will need for tactical coms.  The DX antenna sends out signal more or less horizontally and this causes a “skip” zone so that you will not be received (for example you may have a skip zone of 40 to 600 miles.  This means that anyone within 40 miles of you can hear you just fine, but from 40 to 600 miles, your signal doesn’t get close enough to the ground to be received.

For a radius of 300 to 400 miles, you need to use Near Vertical Incidence (NVIS) sky waves.  This is a fancy term for point it up, it hits the ionosphere about 250 miles up and splashes back down all around you.  This allows two people in neighboring mountain valleys to talk as if the intervening mountain was not there.  The equipment for NVIS operations is simple, portable and does not have to be expensive.

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