9-1-1; What Is Your Emergency?

Wednesday, January 29, 2014

Radio 101: Operations Basics for Telecommunicators & Officers

Taken from Public Safety Communications, January 2014
Written by Charles Nash, Jr., retired in 2010 after a nearly 33 year career as a telecommunicator, supervisor and lead with the Maryland-National Capital Park Police, in Montgomery County, Md. He has been a member of the Mid-Eastern chapter of APCO since the mid-'90s and has been a member of the Editorial Advisory Committee since 2007.

Radio technicians and 9-1-1 telecommunicators can often feel like they're speaking two different languages.  But being able to quickly and effectively communicate with each other, and then relay accurate information to callers and first responders, is a key factor in enhancing public safety.

There are some basic tenets of radio operation that every dispatcher and call-taker should know.  This article is by no means an in-depth or technical review; rather, it's a broad, layman's overview to hopefully increase, or at least refresh, your understanding of on-air courtesy and the principles of propagation (that's techie-speak for "radio wave behavior").

Before we delve into radio usage, we should begin with an understanding of how radios function.

The higher the frequency of a radio signal, the shorter the wavelength and, therefore, the less area covered by the signal.  This of course doesn't take into account location or number of transmitters and antennas, locations of field units (both portable and mobile), field units' reception, terrain, buildings and other factors.  As a telecommunicator, those factors are largely beyond your control, but your radio system's designer and engineers spend countless hours laboring over such details.

Generally speaking, if your agency operates in the 800 MHz bandwidth, the signal will not travel as far as, say, a 700 MHz signal or an ultra-high frequency (UHF) signal, which tends to be located at about 450 MHz or so. The 800 MHz band certainly does not travel anywhere near as far as a very high frequency (VHF) high-band signal at 150 MHz, or the VHF low-band signal in the 30 to 50 MHz range.

Higher frequency also means that more towers and antennas are needed to compensate for that shorter wavelength.  Conversely, lower frequencies require fewer towers and antennas to cover the same area.  Cellphones (which operate at 900 MHz and higher) require many towers, and those towers must be placed close together in order to provide adequate coverage.  Bandwidths of 1.2 GHz, 2.4 GHz and above require a great number of towers to broadcast their extremely short wavelengths over the coverage area.

Though they can't travel very far, higher frequencies can penetrate manmade structures better than lower frequencies can.  This is beneficial for emergency responses to buildings, skyscrapers, apartments/condos, underground parking garages and so on.  Lower frequencies are better for covering vast distances.  A frequency in the VHF low-band or below can sometimes cover hundreds of miles across flat terrain.

Now that we have an understanding of how frequencies and wavelength behave, we're ready to discuss operation.  This top-level review is primarily for telecommunicators, but these basics also apply to field personnel.

The first rule is one that all calltakers and dispatchers should already be familiar with: Always listen before transmitting.  It sounds simple enough, but in an emergency situation it's often the first step people forget.  Make certain that the "air is clear" before speaking, and be sure to first note anything essential before you say what you need to say.

When broadcasting specific information, such as suspect or vehicle description, it's always best to read through the information before transmitting over the radio.  You will be much less likely to stumble over what you're reading if you look at it at least once before speaking.  The few extra moments you take to familiarize yourself with the information will be worth it to speak accurately and not have to repeat yourself.  Be accurate first, and then work on efficiency.

When you're ready to broadcast, key the microphone for a full second (count "one, one thousand" in your head) before speaking, and keep the microphone keyed for a full second after you finish your message.  This will prevent the first or last words from being clipped or garbled.  It takes a radio system a couple of seconds to fully transmit or receive, and also to react to the pressing or releasing of the transmit button.

Be sure to speak across - not directly into - the microphone so your voice is carried clearly.  For field units using a shoulder microphone, remember to turn your head toward the unit; don't expect to be heard clearly if you're talking away from the mic.

Here's a tip that should go without saying: Don't try to have a "cool" radio voice.  Speak slowly, in a natural tone of voice.  If you shout or speak too loudly, you'll over-saturate or distort your signal.  You won't be understood and will have to repeat yourself - wasting valuable seconds of airtime.

A related piece of advice: Don't mumble, and don't "eat" your last word or phrase in the interest of saving airtime.  There's nothing worse than a fast mumbler who trails off at the end.  Speak slowly and clearly, even when chaos is breaking out around you.  Remember, emotions are contagious.  Even if the field units are screaming, your job is to be the steady and calm voice of control, whether in the field or in the comm center.

No matter what the circumstances, try to find the golden ground in between saying too much and not saying enough on the air.  Both of these errors are common forms of "mic fright" that can hinder first responders' ability to get the job done.

Whether you're working with law enforcement, firefighters or EMS, it's important to remember that proper radio operation is as important as following proper protocol when dispatching 9-1-1 calls.  And it's not just telecommunicators and radio techs who need proper radio training.  First responders will spend hundreds if not thousands of hours training in weapons, tactical skills, use of force and the proper usage of tools, apparatus and medical devices - radio ought to be no different.

When used properly, a public safety radio in the professionally-trained hands of a civilian or sworn comm center operator or field staff will help protect the public and maybe help save lives.  Never forget that your radio is vital to your job, citizens' safety and your own life.

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