If you are stuck somewhere you cannot get out of, or are lost, or cannot move due to injury or illness, you want to be able to communicate with someone to come and help you. Let us assume there is no one within earshot of your whistle, or line of sight of your strobe, flashlight or signal mirror, and a fire is either impractical or proves ineffective in alerting people to your situation. What then?
You can rely on perhaps the most effective form of communication known – letting someone reliable know where you plan to be and when you plan to be back. You are more likely to be found if people are looking for you than if nobody knows you are missing. Of more immediate use would be some form of radio communication. First choice would be a charged cell phone. If your cell phone is one of those large screen wonders which gobble battery life, having a recharge with you would be wise. Easiest would be an “external battery”, but a small solar charger or generator (cranked) would work.
But what if there is no cell tower within range of where you are (no bars)? A cell phone would be pretty much useless in that case. Unless it was a satellite phone; those tend to be rather pricey for most people. Another option is two-way radios. These do not depend on a “tower” which may not be in range or is not in service. But they do have range limitations because for the most part, they are unit to unit.
Most common is FRS (Family Radio Service). These are nice little radios, which are easy and cheap to find, and require no license. There is a reason for this: they are limited to very low power, and a fixed, low efficiency antenna. This means that under ideal conditions they may reach a few miles, but weather, terrain or surroundings can reduce the range to well under a mile. If there is not a receiver in range, it is fairly useless. Next up is GMRS (General Mobile Radio Service). This is quite similar in frequency and modulation to FRS, but requires a (no-test) license (per family, not individual) every few years (the only requirement is that you can afford the fee). These have a much higher power limit, and essentially no practical limit on the antenna. These might reach out 20 miles or more under ideal conditions, and even under poor conditions usually reach out more than a mile. Note that many modern FRS radios have GMRS power built in, so can be used for GMRS (with that limited antenna) if you have the license (or are willing to transmit illegally). Of course, a dedicated GMRS unit with detachable antenna, and the most effective portable antenna there is, provides the best service. At a higher cost, of course.
Several decades back, CB was all the rage. There are probably more CBs out there than any other radio type – many of them gathering dust. CB technology is highly susceptible to atmospheric conditions, and as such, has been somewhat supplanted by more modern technologies. With a good radio, an illegal amplifier and the proper antenna, CB can reach out a fair distance. Like most SW (shortwave) radio, it can be bounced off the ionosphere (skip) for astounding range at times. Using a legal car mounted system, range varies from not much to a few miles. You can get a portable CB walkie-talkie, which with a decent antenna can provide up to the same range.
Of course, there are police and business radios. These are essentially limited to use by the organizations and personnel to whom they are licensed, and generally don’t provide any improvement over GMRS, which is similar in technology. If you have legal access, fine; otherwise it is probably not worth the effort.
That leaves “ham” or amateur radios. These fall into two categories, “short range” (line of sight) and “long range”. You can get a technician license for short range UHF and VHF without learning Morse Code. As mentioned, these are line of sight, up to 20 miles or so. There is a network of repeaters which allow you access to the telephone system or “land line” communication between repeaters, giving you almost unlimited range – if there is a working repeater within range of your unit. A more complex license, including Morse Code testing, gives you access to SW equipment which can reach around the world. This pretty much requires a fixed location with power source and an antenna tower, so is essentially out of the question for a survival kit.
So what does this mean to the survivalist? For everyday carry, a cell phone and possibly a recharge capability. If you are part of a group, FRS or better, GMRS radios for everyone. A CB in every vehicle. If you are alone, a CB walkie-talkie. In my bigger kits, I include a small, multi-band receiver for AM, FM and SW.
This should be adequate for survival kits. What about if the SHTF? What should the “prepper” consider? First of all, one set of possible circumstances would be an “EMP”, which can “fry” electronic devices. Even if there is no EMP, the infrastructure is unlikely to remain functional, at least temporarily, for any centralized communication system (cellular, internet, land line, any repeaters). I keep some communications gear in grounded metal boxes (a Faraday cage) “just in case”. Cell phones are most effective – if the cellular system is up. I’ve got a couple “dumb” phones backing up my everyday phone of the same model. CB will likely become much more used, since many people have one in the garage or attic, so have at least one, vehicle based or walkie-talkie. FRS are everywhere, so I’d have a couple in any case, and if I was part of a group, I’d have those or GMRS for everyone plus some spares. I’m a technician class ham, so I have the short range gear, but I’m not counting on it for primary communications. A good SW receiver is nice to get news from far away. Because all these radios operate on different bands, a good scanner or built in scan function is useful. Unless you want to be a ham now, it does not seem worthwhile to get the license or equipment just in case of a possible disaster.