Many people have no idea how critically important communication becomes during and immediately following emergencies and natural disasters. As easy as it is to communicate and access the Internet with mobile devices, it’s just as easy for that network to collapse during a disaster, potentially leaving thousands, if not millions, of people in an information blackout.
Relatively common disasters, such as hurricanes and tornadoes, can take down telephone and Internet systems both locally and regionally. In some cases, even though telephone systems may survive the storm, they become overloaded with communications traffic, leaving some people without the ability to communicate when they may need it most.
While they may be less likely, there are two potentially devastating scenarios that can render most communication systems useless on a large scale. In many cases, this damage is permanent.
1. High Altitude Electromagnetic Pulse (or HEMP) Attack (i.e. a nuclear weapon detonated in the upper atmosphere over a target).
2. Severe Geomagnetic Storm (stemming from an earth-directed solar coronal mass ejection).
Each of these events has its own characteristics and will affect communications equipment in different ways, but preventative measures can be taken to protect your equipment.
The HEMP event is the most devastating to electronic devices because it not only has the ability to damage electronics plugged into the wall (connected to a power grid), but can also damage electronics sitting in the drawer of a wooden desk. Additionally, a HEMP attack can happen with absolutely no prior notice.
The best protection from a HEMP attack is extremely affordable; simply buy a large metal trash can with a snug-fitting lid and line the entire inside with cardboard. With the lid securely attached, this creates a makeshift Faraday cage where your emergency devices and accessories can be safely stored.
A geomagnetic storm is slightly less damaging because we may have opportunity to prepare. With NASA maintaining a close watch on the sun, we can receive advanced warning of up to 16-18 hours before a coronal mass ejection (CME) would strike the Earth. This would leave ample time to take action to prevent damage by unplugging electrical devices from the energy grid, and disconnecting all wiring to and from emergency communication devices, like an antenna on a radio transceiver. Mobile electrical devices should not be affected by a geomagnetic storm. Once the event is over, these devices can be reconnected.
Survival Requires Information
In an emergency or a disaster, your survival is highly dependent upon your ability to obtain real-time local and regional reports from news stations, civilian reporting stations and EMS broadcasts. This information can significantly enhance tactical decisions.
Consider the tactical advantage gained from tornado forecasts and reports. A simple radio equipped to automatically receive live NOAA weather alerts provides immediate notice of threatening weather conditions like potential tornado formation.
As a funnel cloud develops into a tornado, these alerts become more frequent and detailed, including current location, as well as estimated strength, speed and direction of the tornado. This is vital information that helps you decide whether to evacuate or hunker down in the basement.
When a disaster strikes, like the aforementioned tornado, landlines and cell towers have a high risk of destruction, making your cell and home phones useless. With this in mind, you can understand how having a two-way radio transceiver can be a huge benefit.
These stand-alone radio systems are not dependent upon local utilities or infrastructure, and only require another radio with which to communicate. They do need a power source, so you should have extra batteries available, as well as a power generator for backup energy.
Receivers vs. Transceivers
There are many radio receivers on the marketing today capable of receiving a wide range of radio frequencies: HF (High-Frequency), MF (Medium Frequency), VHF (Very High Frequency) and UHF (Ultra High Frequency). However, these radios will only receive signals from other stations, not transmit, so they are limited in their capability to collect information.
On the other hand, transceivers can receive and transmit signals to other stations. The downside here, however, is they are typically limited to a specific band of frequencies. It is a good idea to have both a quality multi-band receiver as well as enough transceiver radios to meet your needs.
Some receivers require manually tuning to find transmitting signals, while others automatically scan the bands and frequencies for you.
Here are some examples of common scanners.
Before you attempt to use any transceiver, you need to become familiar with basic radio etiquette in order to communicate with others.
As a part of your communications protocols, consider adopting certain frequencies to serve as your primary and secondary channels to be used during any emergency. For example, a family equipped with CB (Citizen’s Band) radios in their cars might have prearranged to meet on channel 23 in the even of an emergency.
CB Radio Transceivers
The most common and well-known two-way radio transceiver is the Citizen’s Band Radio, also known as a CB Radio. A license is not required to buy or operate a CB radio (FCC). CB’s typically operate using about 4 watts of output power on frequencies just above HF radios and below VHF radios. They have a nominal effective operating range of about 5 to 10 miles depending upon the antennas used by both radios and the terrain between them.
The operating range of CB radios will be significantly decreased (down to only about a mile or two) in areas bounded by large buildings or mountains. Line of sight provides the maximum range for most short and medium-range radio transmitters.
Under certain atmospheric conditions, the band of frequencies used by CBs can utilize a “skip” phenomenon, where the operating range is greatly improved by bouncing the signal off the ionosphere. Some CB radios can also operate on sidebands of their assigned frequencies (Upper Sideband [USB] and Lower Sideband [LSB]). These sidebands are legally allowed to use higher power output, increasing the effective range of the radio to well beyond 10 to 20 miles. And when atmospheric conditions are right, sideband signals can sometimes reach over hundreds of miles.
CB Radios are widely available and very reasonably priced.
The Truckers Report has excellent detailed information on CB radios. Click here for more.
VHF Radio Transceivers
VHF, or very high frequency, transceivers are used in industry and by various professional operators and government industries, including fire departments, police, coast guard and marine operators to name a few. These radios can be purchased by anyone, but may require a license.
VHF radios operate on frequencies that are higher than HF and MF, but below UHF. VHF radios are more useful for police and fire departments because these frequencies tend to penetrate buildings better. Many VHF radios are built to military standards and are water resistant, impact resistant, and so forth.
Handheld units typically have 5-6 watts of output power and a reliable operating
range of about 5 to 10 miles. As with most other radios, terrain does impact the effective range. Base-station, or fixed, units have various available power outputs ranging from 20 watts to 50 watts, depending upon the unit. Some even have scrambler systems that create a secure connection between your radios.
Because the output power is higher on some mobile and base station units, these radios can operate effectively over much greater distances, ranging as far as 50 to 100 miles depending upon the terrain and antennas used.
Check out this page for more detailed information on VHF radios.
UHF Radio Transceivers
UHF, or ultra-high frequency, radio transceivers are used in business communications, public safety and government applications, as well as others. The operating frequency band ranges from 300 Megahertz (Mhz) up to 3 Gigahertz (Ghz), which covers a lot of applications including television, satellite and cordless radio transmissions.
These frequencies do generally require “line of sight” to operate, but they can penetrate buildings fairly well. GPS satellites, which orbit the earth at an altitude of about 12,000 miles, also operate at the upper end of this spectrum and allow for data transmission and communications with “line of sight” receivers on the surface of the earth, such as ships, aircraft and vehicles.
Iridium satellite telephone systems also utilize the UHF band and have the potential
to be fully functional when other terrestrial telephone systems are down during disasters.
The UHF band is probably the most crowded of all communications bands because it is used by for so many applications. Additionally, the Family Radio Service (FRS) also uses this band between 462-467 Mhz. FRS radios are much more common today as a result of mass sales through major retail outlets like Costco.
Click here for more detailed information on UHF frequencies.
Long Range Transceivers
HF Radio Transceivers
Amateur Radio (HAM) operators, as well as industrial, military and maritime operators use HF, or high frequency, radio transceivers. The FCC has assigned frequencies for various users with HF bands. These bands are lower frequency and tend to bounce off the ionosphere very effectively, resulting in operating ranges of thousands of miles.
You can use both handheld and fixed base station HF units, but the handheld units tend to be much larger than the mobile VHF units due to their higher output power. Base station units generally have a transmitting output power of 100 watts or more.
HF radios can be purchased without a license, but all do require a license to operate. Because they cover extremely long distances, there are special operating protocols that must be observed, although you can easily learn them over a short period of time by simply listening in. An HF radio would be especially useful in the event of any national or world-wide infrastructural blackout caused by a solar flare or HEMP attack.
My advice is to have as many different communications systems as possible to provide several layers of functionality and redundancy. The same goes for the power supply you establish to help operate these systems. In 2010, I experienced first-hand the value of having redundant communications systems. Read the story here.
Semper Veritas / Semper Paratus
Capt. William E. Simpson - USMM
You might also like this article: Survival Engineering and Disaster Preparedness