Telecommunications: Radio Procedures: Equipment and Codes

roughout their shifts, officers use radios to send and receive vital information, call for backup, or identify a suspect or wanted person. Proper knowledge and use of the radio is essential (IN012.7.).

The patrol car radio is usually under or affixed to the dashboard of the patrol car. In some patrol cars, radios are mounted on the vehicle transmission hump or in a metal rack designed for holding electronic equipment. In unmarked or undercover vehicles, the radio may be
mounted under the seat or in the trunk. On police motorcycles, the radio is usually mounted in plain sight behind the handlebars. (IN012.1.)

Their duties include, but are not limited to, answering all incoming emergency and nonemergency calls to the law
enforcement agency, directing callers to other resources as necessary, and gathering information for officers’ calls for service. They also access the FCIC/NCIC systems to
provide vital information to officers who request it. (IN012.5.B.5.)

The basic police radio is generally fitted with at least three switches, levers, or buttons to control volume, squelch, and channel selection (IN012.2.).The plug for the microphone is usually on the front or side of the radio, while power and antenna connections are usually at the rear of the radio case.Most patrol car radios have a channel light and on/off indicator light. Many also have a transmit indicator light.

Officers should plan messages before transmitting them.Though an officer will have to speak quickly in an emergency, the more planned the message is, the more coherent, capable, and professional the officer sounds. (IN012.6.A.)

The officer should speak directly into the microphone in an evenly modulated tone of voice (IN012.5.).

Before voice transmissions, officers should listen to make sure there is no other radio traffic and then depress and
hold the transmit button for approximately one second before speaking (IN012.5.B.1.).

Officers should also be aware that speech habits such as a trailing voice (diminishes in volume), the rate of speech (too fast or too slow), or speaking in monotone or a soft or unclear (mumbling) voice may affect clear communications
(IN012.5.A.1.).

Appropriate radio
system use includes the following:
• law enforcement-related messages to other agencies within the state or
another state
• driver’s license status and driver history
• criminal records checks
• hazardous material queries
• aircraft, boat, and vehicle registration queries
• road condition and weather queries (IN012.5.D.)

An officer should expect no privacy in law enforcement radio transmissions (IN012.5.C.).

Radio protocol describes the procedures of properly constructing and transmitting messages. It also includes proper use of appropriate codes and signals, which varies
among agencies and regions. (IN012.5.B.)

There are three basic codes: Alpha code is a system of words that represents letters in the English alphabet
(e.g., Q codes). In numeric code, a system of numbers represents specific activities or conditions to which an officer might respond; the 10 codes and signals are a numeric system. Alphanumeric code, a combination of letters and numbers, might include officer call signs or auto tags. (IN012.5.B.3.).

The phonetic alphabet is a system of code words for identifying letters in voice communication (IN012.5.B.2.).

Like any effective communication, a properly constructed radio message involves thinking in advance about what needs to be said. It also involves delivering accurate
information in a clear, concise manner (IN012.6.C.).

Messages should follow this basic pattern: identification number, current location, reason for call, and information relative and essential to the situation (IN012.6.)