Emergency Communication by Voice is republished from http://ift.tt/1nr27gs
Staying in Contact When SHTF
When emergencies occur and normal communication goes silent, contacting each other and learning what’s happening become paramount. In a split-second you can have no way to communicate. Facebook is out. Skype won’t work. Email is out, the Internet may be out, and your cell phone has dwindling battery power but won’t connect because all the remaining cell phone resources are being used by emergency, medical, and law enforcement personnel. Even the land line is of limited use. Suddenly you’re on your own. A disaster is not the time to begin thinking about emergency communications. You should have thought about this long before an emergency occurs.
You can listen to emergency broadcast radio (535 to 1605 kHz AM, 88 to 107 MHz FM) and TV (54 to 806 MHz) or high frequency broadcasts from other locations. This can be accomplished using a shortwave radio receiver that lets you monitor news, weather, and status coming from other countries.
International shortwave stations transmit using World Band Radio (special news and special interest programs that are transmitted using shortwave) as well as amateur radio (ham) operators, ships and aircraft, military, weather stations, and science outposts. The Voice of America is one of the major shortwave broadcasters. People who avidly listen to these broadcasts are called Short Wave Listeners (SWLers).
The shortwave receiver covers about 3 MHz up to 30 MHz and receives radio signals from around the world. Signal quality depends on location, time of day—night is better for reception—and transmission strength—up to 1 million watts—far stronger than a 50,000-watt local AM radio station.
Listening is critical to receiving disaster status information, but without telephone, cell phone (900 MHz to 2400 MHz), or WiFi (2.4 to 5.0 GHz), two-way communication is limited to just a few options—Citizen’s Band (CB) radio and Short Wave Ham radio. With these you can talk with your family down the road or neighbors a few miles away.
CB Radio
The Federal Communications Commission (FCC) allocates a frequency range between 26.965 and 27.405 MHz for CB public use communication. There are up to 40 channels in this 11 meter band. CB is popular with truckers, RVers, hikers, campers, road travelers, and cruisers afloat. Fixed, mobile, and hand-held CB transceivers are available that operate short range.
Figure 1 and Figure 2 show two hand-held CB radios. They are advertised to reach out up to 16 or 35 miles. These are line of sight transceivers so work best where no buildings or hills block the signals. Their typical range is about a mile. Even on open sea, CBs can work up to 10 miles, but they work best as short range communicators.
Fig. 1 – Cobra CD80
Fig. 2 – Motorola MR350R
Figure 3 shows a 4 watt Cobra 19 DX mobile transceiver capable of 2-way communication over all 40 CB channels at frequencies of 26.965 MHz up to 27.405 MHz. These are called 11 meter devices.
They can be mounted in a vehicle or boat although some people use them as a standalone transceivers in fixed locations. Operating range depends on the antenna used. Antennas are usually selected for the frequencies intended for use. The antennas for the hand-held transceivers shown in Figures 1 and 2 are just a couple of inches long. For the Cobra in Figure 3, the antenna used can be between 36” and 102” in length.
They can be mounted in a vehicle or boat although some people use them as a standalone transceivers in fixed locations. Operating range depends on the antenna used. Antennas are usually selected for the frequencies intended for use. The antennas for the hand-held transceivers shown in Figures 1 and 2 are just a couple of inches long. For the Cobra in Figure 3, the antenna used can be between 36” and 102” in length.
Figure 4 shows a Midland 5001z CB transceiver that can transmit at 4 watts over all 40 CB channels. Like its smaller handheld cousins, the Midland 5001z operates on the 11 meter band and performs well using line of sight—it’s been known to easily reach out 10 to 20 miles. It can also mount in your vehicle.
Fig. 4 – The Midland 5001z CB transceiver
At the upper end of 2-way CB communication are single sideband CB radios such as the Cobra 29, the Cobra 148 GTL, and the Uniden Bearcat 980 that can output at up to 12 watts. Both sender and receiver must be using the same settings for 2-way communication.
CBers have developed their own slang language based on the first heavy users—truckers, and a Google search can introduce you to hundreds of terms—much like Facebook slang. Thus “break” means “I want to interrupt and get the channel so I can communicate with you.” “Comeback” means “Repeat.” “How do you read me?” means “How strong is my signal?” “Back at yah.” means “Over” or “Back to you.” “Bring it back” asks for an answer back. “You’re bending the needle.” means you have a clear, strong signal. So does “Five by Nine.” And “What’s your 20?” asks for your location. “Clear”—“I’m signing off.”
Shortwave Radio
The next step up is shortwave ham radio. Here the power transmitted is higher—5, 10, 25, and even 50 watts. Ham radio is strictly controlled by the FCC and policing of the authorized frequencies is assisted by the ham operators themselves. Their ham radios operate at frequencies wavelengths of 10 meters, 8 meters, 4 and 2 meters—the higher the frequency, the smaller the wavelength in meters. The equipment is more expensive, but they have much greater range. A nationwide system of repeaters at 144 MHz and 440 MHz enable ham radio signals to reach nearly seamlessly around the world. There are even small 2 and 4 watt, 2 meter “handi-talkie” devices that can communicate up to 50 miles away at 144 MHz.
Figures 5 and 6 show the UV-5R V2+ hand held transceiver made by Bao Feng in China and distributed in the U.S. by Foscam Digital Technologies in Texas. These are now sold under the name “Pofung.”
Baofeng UV-5R V2+ transceivers (Photos courtesy of MCHS ARC – Mount Carmel High School Amateur Radio Club in San Diego, California.)
Each of the Baofeng transceiver radios has an extended battery pack installed giving these devices amazing performance. The Baofeng UV-5R V2+ radio transceiver with extended 7.4V Lithium ion battery pack can transmit on the 2 meter band between 138 and 174 MHz and on the 70 cm band between 400 and 480 MHz. It can also receive transmissions in the public service and aircraft bands as well as the expanded FM broadcast band between 65 and 108 MHz. It can output at 1, 4, or 5 watts.
Figure 7 shows an ICOM 2820H dual band FM transceiver.
Fig. 7 ICOM IC-2820H mobile and base station transceiver. (Photo courtesy of MCHS ARC.)
Like it’s Baofeng cousins, the IC-2820 can transmit on 144-148 MHz and 430-450 MHz. It can receive 118-550 MHz signals with the cellular frequencies blocked. It operates on 13.8 volts DC and transmits at 5W, 15W, and 50W output power on both the 2 meter and 70 centimeter bands.
Figure 8 shows an ICOM IC-910 UHF, VHF, and satellite transceiver.
Fig. 8 – ICOM IC-910 satellite transceiver. (Photo courtesy of MCHS ARC.)
Ham radio operator signals travel long distances using ground wave, ionosphere bounce, and satellite bounce. There have even been communication transactions between ground stations and orbiting space craft. The type and length of antenna are key factors in how far a shortwave signal will travel. Repeaters mounted on the tops of mountains and high hills enable the signals to get around obstacles and keep signals moving out across the landscape.
During the Hurricane Katrina disaster, ham radio operators were instrumental in sharing information and news to everyone in and around the affected area. Hams also used a phone patch on their equipment to enable disaster victims to talk with family and friends located hundreds of miles from the scene.
Ham radio base stations are easily identified by the tall antennas (antenna farms) near buildings and long, 102 inch whip antennas bent over vehicles. Hams are key players in our nation’s emergency communication infrastructure. We are fortunate they are among us.
If you can’t afford a ham radio license and multiple shortwave comm equipment, then a hand-held CB radio can be ideal for quick and easy communication in a changing environment where mobility at a moment’s notice is critical. You must use what you feel is best for you. Your survival may well depend on it.
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