A two-way radio is a radio that can both transmit and receive (a transceiver), unlike a broadcast receiver which only receives content. A two-way radio (transceiver) allows the operator to have a conversation with other similar radios operating on the same radio frequency (channel). Two-way radios are available in mobile, stationary base and hand-held portable configurations. Hand-held radios are often called walkie-talkies, handie-talkies, or just hand-helds.

Two-way radio systems usually operate in a half-duplex mode; that is, the operator can talk, or he can listen, but not at the same time. A push-to-talk or Press To Transmit button activates the transmitter; when it is released the receiver is active. A mobile phone or cellular telephone is an example of a two-way radio that both transmits and receives at the same time, ie in full-duplex mode. Full-duplex is generally achieved by the use of two different frequencies or by frequency-sharing methods to carry the two directions of the conversation simultaneously. Methods for mitigating the self interference caused by simultaneous same-frequency transmission and reception include using two antennas, or dynamic solid-state filters

It’s very important to maintain communication with your family or friends during a disaster as it is your only way of knowing what’s happening and what to do next in an emergency situation. That’s why survival radios are a top necessity when building your emergency survival kit. 

You may be wondering why we should bother using a radio when we have easier ways of communicating nowadays by using our cell phones, laptops, etc.; here’s why:      

Cell phone communications has a lot of vulnerabilities like being dependent on cell sites which could be affected in disasters like floods and earth quakes, low battery life, etc. which makes it a poor choice for communication solutions or long-term emergencies.  

As mentioned earlier heavy winds and flooding can disrupt cell towers and cables causing loss of signal like what happened during Hurricane Sandy.          

Cell sites or towers operates on AC power alone and this could be a big problem when the main power source is disrupted which is mostly the case during disasters. Most cell towers use generators for backup power supply but generators are very short-term solution as they require fuel that has to be replenished more often.   

Cell phone communication depends on back haul systems that are not always reliable since it is wired which could still be affected by floods and earth quakes.      

Cell phones have very short battery life which would only last for a day or three. This could be a big problem for long term disasters or emergency because you won’t be able to use your cell phone unless you have a local power to back it up. 

Cell phones require satellites to establish a stable signal for communication. Unfortunately, satellites are vulnerable to physical attacks, hackers, and solar storms. When power and commercial lines are down the only way to be able to connect to the outside world is by using radios as emergency communication equipment because they do not depend on AC power, satellites, or commercial lines to establish a signal for communication. 

Five two-way radio best practices for emergencies

A lot of things have to be done right when using two-way radios in an emergency. Some of these tips may seem like common sense, but common sense often flies out the window amid the stress, anxiety and chaos of a crisis. Be sure you know these five points in advance:

You must be prepared. If you are unfamiliar with two-way radios, take some time to learn how they function and what features your device offers (such as emergency alerts). When you’re getting trained on a new radio, insist on asking what you would do differently in an emergency.

When talking, less is more. Be brief and efficient — know what you are going to say before talking into the microphone; otherwise you’ll tie up the channel while thinking of what to say. (Remember: When you use the push-to-talk button, you’re preventing other people from talking on the same frequency). 

Don’t mind your manners. While you must respect fellow users, you don’t have to be polite by saying “please” or “thank you.”

Repetition rocks. Repeat back information you receive to confirm that you heard correctly.

You have no privacy. Remember that group conversations are not private on open channels — any other radio user within range can hear what you’re saying by tuning to your frequency. Actually, this is a big plus in emergency broadcasts and SOS situations where the operator wants to relay a message to as many people as possible.

Cell phones aren’t the answer in an emergency

The Columbine school shooting in 1999 marked one of the first times where easy access to cell phones played a role in a major emergency. Unfortunately, students could call newscasters, but could not convey accurate information, creating conflicting reports that confused first responders. And 911 dispatchers were flooded with calls, which did more harm than good.

Fourteen years later at the Boston Marathon bombing, cellular networks either slowed dramatically or intermittently stopped working altogether. Runners and their loved ones could not connect, and victims had trouble communicating with emergency responders. That frustrating scene of over-strained cellular networks has become familiar in such disasters as the September 11 attacks and Hurricane Sandy.

For all the reliance we place on cell phones, they have failed repeatedly when needed most. In almost every instance, congestion is the problem. Too many people try to use their phones at the same time to get help or tell family and friends they are okay. Two-way radios excel where cell phones fall short because they have dedicated bandwidth and a limited number of users. They’re also much easier to use — usually it’s not much more than pushing one button and talking.

With the addition of bi-directional amplifiers, distributed antenna systems, and repeaters, reliable two-way radio coverage can be extended throughout a facility or across a campus in areas where cell phone signals cannot reach.

Using 2-way radios is very simple. There are several models to choose from, each with a variety of features to meet all your communication needs. The handsets are lightweight and easy to carry, making these walkie-talkies fun to use. 

10 Safety Tips
1. Know how to use your two way radio. Make sure all users know how to use the handsets on the model you've purchased. Practice while standing a block away from each other so you both know what to expect when using the radios.

2. Establish a call pattern with your group. Determine which channel you'll use and when you'll meet on the radio. Then agree how often you'll check in with each other.

3. Test the range beforehand. When your group is walking, establish a route. Then check in with each other along that route so you're sure there are no "dead spots".

4. Before leaving, check the batteries in both 2-way radio handsets. AAA batteries generally do not last as long as AA batteries, so be sure to check them more often. If in doubt, always carry a spare set. Between call-in times, the radio can also be turned off to preserve battery life.

5. Always keep extra batteries for the two-way handsets on hand. If the batteries are rechargeable, make sure they remain charged and available at all times. Some Motorola two way radios have a battery power-save function; this slows the battery power expenditure when the handset remains on for long periods. 

6. Purchase walkie-talkie sets sturdy enough to withstand your activities. If your are extremely active and the handset needs extra protection, consider purchasing a rugged case for it.

7. A 2-way radio are not private, your can be approached by strangers over the airwaves. Teach them how to best handle this situation and ways to remain answer.

8. Remember you're sharing channels with others and many people can listen in. Teach your group how to avoid giving exact locations over the radio; Use codes and checkpoints to identify locations like whit GPS coordinates.

9. Figure out a back-up plan. Decide how to best handle a situation if the batteries in the walkie-talkie die or there are 'dead spots' during transmission. For safety, make sure your group has the phone numbers to the base.

10. When on a mountain or on the water, two-way radios should never replace the buddy system. Because of terrain, especially in wilderness areas, there may be dead spots where 2-ways can't transmit. Have a plan for communicating when you're not all together; make sure everyone in your party understands and agrees to it. 
Two-way radios are the perfect solution for staying connected to all members in the group.

So how would you communicate with your family or get help if communications go down? If you found yourself in the middle of a wide-scale disaster such as a hurricane or other catastrophe and you had no government coming to help for a while, how would you communicate with your family or others? What if the power grid went down?

You won’t be able to rely on your cell phone. There are alternatives, however. This is a pretty long article that goes into some good detail, but if you want the short answer, this is what you need.

I’ll go over the basics of some emergency communication methods but if you want more detail, check out Personal Emergency Communications: Staying in Touch Post-Disaster: Technology, Gear and Planning.

Short-term emergencies have shown the limitations of using cell phones to coordinate with each other. Even if the towers are operational, they can’t handle the added traffic of millions of people trying to get a hold of loved ones – or help. Ever had trouble calling your mother on the morning of Mother’s Day?

During many recent events, cell phone service wasn’t an option for many for days. The system became seriously overloaded on 9/11 so calls wouldn’t go through, 70% of the towers went down during Katrina and were down for days, and most areas haven’t been adequately improved across the US.

These won’t be isolated events. Don’t think that because you live in a large metropolitan area that you’re safer. A quick look at some of the things that went on during Hurricane Sandy in NY will show that the government has a lot to deal with in addition to just trying to get your cell phone service back up so even though that was a pretty short-term event, it caused a lot of problems.

Here are just a few issues that would affect you being able to pull out your iPhone to call up people:

Cell phone communication has a lot of vulnerabilities that make it a poor solution for widespread or long-term emergencies.

Heavy winds or flooding can disrupt the cables between towers such as during Hurricane Sandy.

Cell towers require AC power to operate so if they don’t have an automatic backup system, they stop. Keep in mind that a lot of towers are just glorified antennas on the tops of buildings or mountains and backup power, such as an emergency generator, is a very short-term solution. Generators require fuel and that fuel has to be replenished quite often. In a lot of cases, the only backup power available is a bank of batteries that stop charging when the main power system stops.

Backhaul systems (essentially the system that connects and/or allows overflow from outer systems to the core, often including other carriers) aren’t always reliable. A lot of this system is wired but has been expanded to microwave and other systems.

Most cell phones will only stay charged for a day or three. If you don’t have local power to keep it up, when the system does come back up, you won’t be able to talk to it.

Cell phones require satellites, which are vulnerable to hackers, physical attack, or solar storms.

Now don’t get me wrong, for day-to-day emergencies, such as getting a flat tire, a cell phone usually works pretty well. It’s just a crappy solution for big emergencies. They’ll be pretty useless if the national grid goes down due to a cyber attack, EMP or CME, which is actually a lot more likely than you might think.

One cool idea that’s coming out is the go Tenna cell phone radio antenna system. Your cell phone connects to it via Bluetooth and an app, and the signal is sent and received through an encrypted radio signal. How awesome is that? It won’t be able to reach to the other side of a city but you should be able to locate your family if they’re in the area and maybe even communicate with others if they have the system.

So if you can’t rely on cell phone service, what other options do you have?

Before you key your mike, gather your thoughts about what you are going to say. Many people with radios have a tendency to talk and/or repeat too much. Say what you need to say without unnecessary repeats. Keep in mind that you must strive to get your message through the first time.

Practicing proper day-to-day radio procedures will make emergency radio procedures automatic and reduces confusion. Another way of saying this is that the secret to working quickly and efficiently in an emergency is to use common approved radio communication procedures and guidelines and practice, practice, practice.

1st, you MUST give the radio callsign of the station you are calling. This alerts that station that they are being called and that they should listen to determine who is calling.

2nd; say "THIS IS". The called station knows your tactical call follows. This is extremely important in cases where there is a lot of confusion or poor signal conditions.

3rd, give your radio callsign. Don't give your first name. Radio callsigns are important and first names are not, egos notwithstanding. Remember, we are licensed for radio to radio NOT person to person communications. You WILL create confusion if you reverse the first three steps, especially during emergencies and when you are communicating with a dispatcher or people who do not know you. If your practice is the reverse of the "norm", you will not be able to change "on the fly" especially during the added stress brought on by an emergency situation.

4th, give your message. Speak clearly. Don't speak too fast especially if the message needs to be written down. Pause after logical phrases. Do not use the word "break" when you pause. It is confusing, wastes time and has other connotations. Merely unkey and pause. If the other station has questions, they should key up and make their request known. This also permits other stations to break in if they have emergency traffic.

5th, you can end your conversation with “CLEAR” however it isn’t required.