National Traffic System

The National Traffic System (NTS) is an organized network of amateur radio operators sponsored by the American Radio Relay League for the purpose of relaying messages throughout the U.S. and Canada.

During normal times, these messages are routine greetings ("Happy birthday Aunt Mary") and keep the system well oiled and the operators trained so that everything works when needed. When there is an emergency or disaster NTS works closely with the Amateur Radio Emergency Service to provide emergency communications. The most common type of disaster-related messages are "health and welfare" inquiries and notifications into and out of the area affected by the disaster.

In time of disaster, it is easy to expand the system by simply creating additional meeting times for the nets with high volume, or by setting up a specific "trunk line" between two points.

Traffic passing by formal relay (via amateur radio) originates from the founding of the American Radio Relay League. The NTS as it exists today was first outlined by George Hart, W1NJM (died 24 March 2013) in "New National Traffic Plan: ARRL Maps New Traffic Organization for All Amateurs" as part of the September 1949 issue of QST. While traffic passing between amateur radio operators was nothing new, Hart's system extended coverage of traffic capability in a uniform manner across the U.S. and Canada, creating formal section and area nets devoted to handling NTS-organized traffic.

NTS is defined using geographic areas. The U.S. is divided into areas that approximate time zones. Areas are divided into regions, and regions into sections that correspond to a state. Each of these subdivisions has nets for collecting and distributing traffic. A net is nothing more than a time of day and a radio frequency where the appropriate group of amateur operators can meet to send the messages on their way. ARRL Radiogram traffic typically begins and ends its journey at local nets, often through nearby repeaters. Local nets typically involve city or county-wide coverage on VHF (2-metre band) or UHF (70 cm band), and although the ARRL does not endorse a single mode for traffic passing, messages are typically relayed by voice at this level.

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