The Basics:

Here are some of the most common terms you’ll hear referencing communications equipment. If you just want a quick overview on the must-know terms, this section of our radio terminology glossary should help.

Two-Way Radio: A device that transmits and receives voice communication. There are desktop transceiver units, as well as handheld radios often referred to as walkie-talkies.

Repeater: A two-way repeater is a device that receives and re-broadcasts your signal to provide more coverage. For example, law enforcement teams may use repeaters so they can amplify their communication range across a large town.

Base Station: A desktop radio device that transmits and receives voice communication. It’s the central hub of the communications system, and it is often used by the head dispatcher in an organization.

Channel: The channel is the frequency on which radios communicate. Channels vary depending on the radio’s make and model.

Analog: Analog radios send and receive electrical signals, similar to sound waves.

Digital: Digital radios send and receive signals as number patterns, similar to computers.

Push-to-Talk: The PTT button is included on all handheld radios. You press it when you want to transmit your voice.

Two Way Direct carries AT&T Enhanced Push-to-Talk solutions that add walkie-talkie functionality to mobile devices for nationwide coverage and easy communication with the push of a button.

Programming: Radios need to be programmed so they can all connect on the same channel properly. Our in-house experts can help with radio programming, and we guarantee the compatibility of all new products with your existing system. Ask us about integrating new technology with devices you already own!

Frequency/Band: The frequency/band is what transmits the signal, and what the channel operates on. There are three radio frequencies, and the radio terminology for frequencies is covered in more detail below.

Radio Terminology Glossary: Frequency Ranges

High Frequency (HF): High frequency is the range of frequencies between 3 and 30 MHz on the radio wave spectrum. HF radio is ideal for communicating long distances.

Very-high Frequency (VHF): Very-high frequency is the range of frequencies between 30 to 300 MHz on the radio wave spectrum. VHF radio is ideal for outdoor environments where line-of-sight between each device is not obstructed.

Ultra-high Frequency (UHF): Ultra-high frequency is the range of frequencies between 300 and 3,000 MHz (3GHz) on the radio wave spectrum. UHF radio is ideal for communicating indoors, as UHF transmissions penetrate obstacles more effectively.

Radio Terminology Glossary: Uncommon Terms

Squelch: Some devices have a squelch feature that cuts the signal when the radio isn’t in use to prevent hiss and crackle sounds.

Scan: Some radios have a scan feature that automatically scans through various radio channels to find channels with activity on them.

Frequency Division Multiple Access (FDMA): Commonly used in satellite communication, FDMA allocates a specific channel to an individual user.

Relay Delay: Prevents transmission delays when using a repeater by keeping the repeater’s transmission open for 0 to 7 seconds after a user releases the PTT switch. This helps to facilitate more natural conversations without accidental interruptions.

Radio Terminology Glossary: FirstNet Terms

FirstNet (First Responder Network Authority): A nationwide broadband network reserved for first responders. FirstNet includes advanced services, applications, and purpose-built devices that help emergency personnel to communicate as efficiently as possible.

Situational Awareness and Detection: FirstNet uses various tools such as geo-location, mobile sensors, and other enhanced location services. This provides live locational information to first responders.

Multi-Agency Communication and Collaboration: FirstNet makes it possible for emergency teams to collaborate using dynamic chat groups, texts, voice messages, images, and videos.

Internet of Things (IoT) and Smart City Initiatives: FirstNet makes it possible for emergency personnel to send and receive mass notifications.

Rural Coverage: FirstNet provides viable communications solutions over vast rural areas.

Interoperability: Interoperability means that devices can communicate across multiple channel types, such as Land Mobile Radio (LMR) and Long-Term Evolution (LTE) cellular networks.

Radio Terminology Glossary: Devices and Accessories

Mobile Two-Way Radios: Mobile two-way radios are radios that can be used from a vehicle. They’re usually mounted in the dash, and are commonly used by truck drivers, law enforcement officers, firefighters, and other emergency services.

Wireless PA System: A wireless PA system can connect to your radio system, so you can broadcast messages loudly to a large group of people. They’re commonly used for emergency situations, in schools, in warehouses, and at outdoor sports events.

Call Boxes: Call boxes  stationary units that can be set up in strategic locations so anyone can access radio communication as needed. For example: call boxes might be set up throughout a large warehouse so workers who don’t carry handheld radios can still communicate with dispatch.

Antennas: Antennas transmit your radio signal and extend your radio coverage.

Chargers: Battery chargers recharge your radio’s batteries. There are single-unit and multi-unit chargers available.

Speaker Microphones: Speaker microphones attach to your collar, allowing for discreet, private, and convenient communication.

Earpieces: Radio earpieces allow you to hear incoming transmissions privately and discreetly.

Surveillance Kits: Surveillance kits generally include a microphone and clear coil earpiece. They’re commonly used by the Secret Service and other security personnel.

Headsets: Radio headsets are headphones that include a microphone. They’re ideal for noisy environments or for applications that require hands-free operation. Many headsets include noise-canceling features so they can be used in helicopters and other loud areas.

Carry Cases: Carry cases protect your radio from the elements, while making them more easily accessible.

Belt Clips: Belt clips attach your radio to your belt, so it’s always ready when you need it.