The next most important radio for preppers is a shortwave radio. Shortwave radio is generally defined as the part of the radio spectrum between 3.0 megahertz (Mhz) and 30.0 megahertz (Mhz). This is referred to as High Frequency, or HF spectrum. There are all kinds of transmissions you will hear on shortwave– Ham radio operators, International shortwave broadcasters, military communications, clandestine stations, numbers stations, and a whole lot more. You will also hear many different modes of communications as well. The bulk of what you will hear will be either standard AM broadcasting and SSB or Single Sideband transmissions.
I cannot stress strongly enough that every prepper needs a good quality shortwave receiver . With the advent of satellite and digital communications, the use of shortwave has diminished somewhat over the years, but there are still two types of stations you will want to monitor. These are the international shortwave broadcasts transmitted by foreign countries and Ham radio operators. It is interesting to listen to the news from foreign broadcast stations. In the cold war days it was viewed as propaganda. In today’s world, who is to say what constitutes propaganda considering our own MSM.
There are hundreds of shortwave receivers out there, and I will not recommend any particular one. What I can do is tell you what types of features you need and let you find the radio that suits your taste.
For general use you need one that receives AM and SSB. We defined these modes above. AM is a standard mode and they all will perform that function. In order to receive SSB stations, the radio must have some additional circuitry known as a BFO or Beat Frequency Oscillator. Careful reading of the specifications will tell you whether or not it will receive SSB signals. Look for ones that use a Phase Lock Loop or PLL tuning circuit. This type of circuit prevents frequency drift.
The HF spectrum is divided up for specific uses. Groups of frequencies known as bands are assigned to International shortwave stations, Hams, marine, aircraft, and other users. You can find many charts on the Internet that will display where you can find the stations you are looking for.
The higher end receivers also provide for the use of something called a pan adapter. What a pan adapter does is display a range of frequencies on a screen that shows what signals your radio is currently receiving. For example, you tune your radio to a specific frequency to listen to a broadcast. With a pan adapter connected to your radio, you can see other signals above and below where you are listening on the display. These signals are displayed as pips on the display, and the height of the pip is directly proportional to the strength of the signal. This is a good way to find other stations to listen to. There are pan adapters that use your computer screen and pan adapters that are stand-alone units not requiring a computer. Search the Internet for pan adapter.
If you are looking for something to listen to, you have to constantly turn the knob to tune up and down the band. With a pan adapter, you can park the receiver on one frequency and sit back and watch for other signals to show up above and below the frequency you are tuned to. This makes it much easier to find stations that have very short transmissions, such as military and clandestine radio stations.
The main things you would want to listen to would be the International Shortwave Broadcast stations and Ham radio operators. Hams generally like to talk a lot and don’t practice much OPSEC. There are other neat things though. Have you ever wondered how commercial aircraft communicate when they are over the mid Atlantic Ocean? It is done via USB on HF frequencies. In the cold war days, there were a lot of numbers stations. These were stations that would transmit long lists of numbers and were thought to be how foreign operatives received their coded information while in the U.S. These stations are still on HF today. There is even a 2013 movie about a CIA numbers station called The Numbers Station . Search for shortwave numbers stations.
One very important point to make here is that virtually all Ham transceivers that cover the 3.0 to 30 Mhz spectrum have continuous coverage receivers in them. So, if you have a Ham transceiver, you probably already have a high end shortwave receiver built in.
The last item for discussion is amateur or Ham radio.
Every prepper should have a Ham license. The Technician class license is not hard to obtain, and it will give you the license you need to transmit and receive on specified portions of the amateur bands.
Remember that a group of frequencies is known as a band. These bands are assigned names based on the frequencies they cover. For example, the 80 meter band covers the HF frequencies between 3.5 and 4.0 Mhz. The 40 meter band covers the HF frequencies between 7.0 and 7.30 Mhz, while the 2 meter band covers the VHF or Very High Frequencies between 144.0 and 148.0 Mhz. The bands above 2 meters are generally referred to by their frequency. The 222 band covers the VHF frequencies between 222.0 and 225 Mhz. The 440 band covers the UHF or Ultra High Frequencies between 420.0 and 450 Mhz, while the 900 band covers the UHF frequencies between 902 and 928 Mhz. A quick search of the Internet for amateur radio band plans will net you a lot of charts and graphs depicting all the bands and their sub uses.
One thing about Ham radio is that it covers an extremely wide range of frequencies. When using the HF bands, depending on who you want to talk to will determine what frequencies you will use. If you want to talk to someone in Europe, Africa, South America, or the Far East, you would most likely use the higher frequencies in the HF spectrum. These would be the 10, 12, 15, 17, and 20 meter Ham bands. If you want to talk to other Hams in the United States, you would most likely use the 40, 80, and 160 meter bands. Something referred to as propagation will determine your actual shortwave band usage. The sun affects propagation, and therefore you will use different bands at different times of the day depending on how far away you want to talk. Propagation is a science unto itself and way beyond discussion in this document. Search the Internet for propagation.
Over the last several years some manufacturers have begun marketing what are known as Software Defined Radios  or SDR. These radios are just a box that you plug into your computer. They don’t have any knobs or a display; all control of the radio is done with software on your personal computer. Any prepper see a problem with this? In order to use your radio you have to have a very powerful personal computer hooked up to it all of the time. Not only must the software in the SDR be kept up to date, you must keep your computer software and drivers up to date as well. And if your computer breaks or locks up, there goes your Ham radio. Whenever someone asks me about SDR’s, I tell them that I don’t mind having a computer in my radio, but I don’t want my radio to be in a computer. I don’t want to have to rely on Bill Gates to use my Ham radio.
Hams are hooking radios to computers and the Internet and doing some really neat things. Using certain talk groups on a DMR repeater will allow you to talk to Hams in foreign countries on your VHF/UHF handheld. Using D-star you can dial up repeaters in foreign countries and talk to Hams there. Using IRLP you can dial up any other IRLP repeater anywhere. But all of this depends on computers and the Internet. My advice to preppers is to not base your emergency communications on anything that uses computers, cell phones, or the Internet. You need to be self sufficient and be able to operate in a stand alone environment.
Almost all current HF Ham radios contain computers for Digital Signal Processing (DSP) and other functions, but you don’t need a computer to operate them. Search for Elecraft, Yaesu, Kenwood, and Icom amateur radios. I won’t tell you what brand to buy, but they are listed in the order I recommend them to others when asked. Pay your money and take your choice.
For local coverage as a general rule, you will use 2 meters, 220, and 440 most likely over a repeater. Repeaters for Hams work the same way as they do for public service agencies in the scanning world. Repeaters are coordinated by frequency coordinators, and they usually have a website for their area. Search the Internet for coordinated Ham repeaters.
The basic mode of transmission used by Hams in VHF and UHF is FM. Probably 99 percent of communications are in FM mode, but digital communications are beginning to take hold. There are currently three types of digital modes, none of which are compatible with each other and are promoted by a specific manufacturer. Icom radio promotes a mode called D-star. Yaesu radio promotes a mode called System Fusion. Many Hams are using the Motorola Mototrbo mode known as Digital Mobile Radio or DMR. As I said before, none of these modes are compatible with each other, which has caused some consternation among Hams.
An interesting note about these digital modes. None of them currently can be understood on a scanner. Public service and trunked radio systems use a digital mode known as P25, and your digital scanner can decode that. But the digital scanners currently on the market can not decode D-star, System Fusion, or DMR. There is one fellow in a foreign country marketing a scanner that purportedly will decode P25 and DMR and System Fusion, but there’s nothing from any of the major scanner makers yet. This makes for interesting OPSEC considerations. Your group could purchase several of one type of digital mode and use simplex frequencies for your comms. This would eliminate anyone understanding you on a scanner and only another Ham with the same mode would be able to understand you.
The popularity of these modes varies around the country. Where I live, there is very little D-star activity, but there is some DMR activity. System Fusion, however, is catching on rapidly and has already overtaken the other two in popularity. Once again you need to do your homework for where you live to see which mode is the most popular before buying a radio. There are currently no manufacturers who make one radio that does all three of these modes, so you have to pick one. One thing is for sure, it will take a long time but digital modes will eventually replace FM on the VHF/UHF Ham bands.
One reason for this is that the majority of Ham repeaters consist of old obsolete commercial equipment that has been modified to operate on Ham frequencies. This is equipment from manufacturers, such as Motorola and GE, that will eventually break down and no parts will be available to repair it. It was old and obsolete when the Hams got it. Since Motorola no longer makes any commercial analog equipment, what will the Hams do? In a few years the commercial equipment currently in service will be obsolete and available on the Ham market, but it will be only digital. You see where I am going with this. It will be wise to convert to some form of digital or your repeater goes off the air.
Our radio club experienced this just last year. Our old Motorola analog repeater finally died, and we could find no parts to repair it. We purchased a new Motorola repeater that does analog and DMR and put it on the air. It was very expensive but should be good for many years. (Yes, it was the last model commercial repeater that Motorola makes that does both analog and digital.)
The reason Motorola even made a mixed mode repeater was to accommodate the commercial market during its change over from analog to digital. From now on all their equipment is strictly digital.
In the old days, AM was used on the HF Ham bands, but then a new fangled mode called SSB came out. It took a lot of years but SSB finally replaced AM. Technology marches on, and eventually you convert or you will have no one to talk to.
I recommend that you find a local Ham radio club and use local Hams as a resource. Just be careful. Don’t go to a Ham radio club and announce that you are a prepper. I know some Hams who are very anti-prepper. Use the club as a source of information. Some clubs provide classes to help you get your Technician license. Then working with club members you can determine who else might share your opinions and objectives. Clubs who promote the American Radio Relay League’s (ARRL) Amateur Radio Emergency Service (ARES) program would be a good place to start, since they are geared toward emergency services. Search ARRL and ARES.
The most important thing to take away from all of this is to listen, listen, and then listen some more. The more you listen the more you will learn, and what you hear might save your life someday.