ARRL Radiogram: How to Write and Send a Formal Message

Long before text messages, amateur radio operators were relaying written messages across the country, and the format they used is still alive. The ARRL radiogram is a standard form for a formal message that is passed from one radio operator to another until it reaches its destination. It looks strict at first, with a numbered preamble, a precedence letter and a word count, but every part has a purpose, and once you know the pattern a radiogram is easy to fill in. This guide explains the parts of the form, how the word count works, what the handling codes mean and how a message travels through the National Traffic System. It is based on the published description of the format and the ARRL’s NTS pages, so check the current ARRL forms before you use it for real traffic.

What a Radiogram Is

According to the encyclopedia article on the ARRL radiogram, it is a piece of formal written message traffic routed by a network of amateur radio operators through traffic nets, called the National Traffic System, or NTS. It consists of a plain text message and the relevant headers that are placed into a traffic net by an operator. Each radiogram is relayed, possibly through several other operators, to someone who volunteers to deliver the message to its destination. Within the United States, amateur radio operators can send and deliver radiograms on behalf of any member of the public, which is one type of third-party traffic that FCC rules specifically permit.

The reason for the standard form is speed and reliability. A radiogram always lists its headers in the same order, so operators can read and understand them without spoken labels. This matters most in hectic, stressful situations such as a disaster, when many parties ask radio operators to move messages in and out of an affected area. The order is logical enough that many operators have memorised it and can send and receive radiograms without the form in front of them. The ARRL says on its NTS page that during disasters or other emergencies, radiograms are used to communicate information critical to saving lives or property, or to inquire about the health or welfare of a disaster victim.

The Four Parts of a Message

A radiogram has four parts: the preamble, the address, the text and the signature. The preamble contains the information needed to track the message as it passes through the system. It is created by the station of origin and, except for the check, is not changed by any station that relays or delivers the message. The address names and locates the recipient. The text contains the message itself, as authorised by the person for whom it is sent. The signature closes the message. When it is transmitted, the text is separated from the address and the signature by the word BREAK on voice or the prosign BT on CW, so the receiving operator knows where it begins and ends. The words BREAK and BT are not counted as groups.

The Preamble in Detail

The preamble has several fields, and some are optional. Their order is fixed.

1. Message number. Chosen by the originating station, it is on every message and stays with it to the point of delivery. Use digits only, with no letters, leading zeros or dashes. Many stations begin again at 1 at the start of a year or a month.
2. Precedence. Letters showing the priority of the message, on every message. See below.
3. Handling instructions (HX). Optional, and used only when a particular need exists.
4. Station of origin. The call sign of the amateur station that first put the message into the amateur system. It stays with the message, and service messages about handling are sent to this station.
5. Check. The number of word groups in the text. It is the one part of the preamble that the handling stations verify.
6. Place of origin. The city and state of the person for whom the message was created, which is not necessarily the location of the station of origin.
7. Time filed. Optional, used when the filing time matters. It is given in 24-hour format with a Z for UTC, or marked with a time zone or an L for local time. UTC is preferred, because the NTS covers many time zones.
8. Month and day. Required on every message, as a three-letter month abbreviation followed by the day in figures without a leading zero. If a time is given, the date and time must agree.

Precedence: How Urgent Is It?

The precedence tells operators which messages to handle first, which is vital when circuits are busy. The format recognises these classes, summarised from the ARRL’s definitions as quoted in the article.

The ARRL notes that these classes are not meant to prohibit handling lower-level traffic until all higher levels are passed, and that common sense dictates handling higher precedence traffic first when possible. For tests and exercises, a precedence may be preceded by the word TEST, and the text should say that it is a test message or an exercise, which helps listeners avoid undue alarm. A service message, marked SVC before the message number, is a message between stations about handling or delivery and takes the same precedence as the message it refers to.

Handling Instructions (HX Codes)

Handling instructions are optional and should be used only if a need exists. If they are used, they must stay with the message to the point of delivery. The codes begin with HX and a letter. Some examples from the published list are HXA, which means delivery by email or text message is preferred, HXC, which asks the delivering station to report the date and time of delivery, HXE, which asks the delivering station to get a reply from the addressee, and HXG, which allows cancellation if postage or other expense is involved. HXR asks for confirmation that the addressee has read the message and is reserved for emergency, priority and certified messages. More than one code may be combined, as in HXAC, provided no numbers are inserted. The ARRL publishes the full list on its NTS pages, so use the current version rather than relying on memory.

The Address and the Text

The address follows the preamble. The first line contains the full name of the addressee, written as it would most likely be found in the local telephone directory. The next lines give the street address, the city, state and ZIP code without punctuation, and a telephone number as groups of digits without hyphens. The latest version of the form also has a space for an email address. An optional op note may follow the address, introduced by the words OP NOTE, with information for the handling operators, such as the best time to call. It is not part of the message that is delivered.

The text is the part the person wants to send. An operator never originates a message for a person without that person’s permission. The text is divided into groups, five or ten to a line to make counting easy, and is usually limited to 25 words or fewer. Punctuation is not used except for a few special cases. The letter X stands for a period and counts as a group of its own, but it is never used as the last group. A slash may be used within a group, such as 304/BA. The letter R is used in place of a decimal in mixed figure groups, so 146.670 becomes 146R670. Other punctuation is spelled out, for example QUERY for a question, and counted as a group. Words such as love or regards are placed in the text and not in the signature.

For frequently sent messages, the ARRL has a brevity code called numbered radiograms. Each of 48 numbers stands for a full sentence, and the number is spelled out and preceded by the procedure word ARL. For instance, ARL FORTY SIX stands for a birthday greeting, and it counts as three words. The sentence is expanded when the message is delivered outside the system.

Counting the Check

The check is the total number of groups in the text, counted between the start and end prosigns but not including those prosigns. Operators use it to verify that the text was copied correctly: if the receiving operator counts a different number from the check, something was lost or added, and the sender can repeat the part that is in doubt. Slashes and R decimals within a group do not create new groups, while a standalone X or a spelled-out punctuation word does. Here is a short example, in which every name and number is invented for illustration.

Preamble: NR 4 R N0CALL 9 SPRINGFIELD IL DEC 3
Address: JANE SMITH / 123 MAIN STREET / SPRINGFIELD IL 62701 / 217 555 0100
Text: HAPPY BIRTHDAY X HOPE YOU HAVE A GREAT DAY
Signature: TOM

The text has nine groups, which are HAPPY, BIRTHDAY, X, HOPE, YOU, HAVE, A, GREAT and DAY, so the check is 9. Pay attention to the order of the preamble: number, precedence, station of origin, check, place of origin and then the date. That example uses no optional fields. When you send it on voice, the operator reads the groups exactly as written and uses phonetics for call signs and unclear words, as in our guide to the ham radio phonetic alphabet. On CW, the prosign BT separates the parts, and our article on CW abbreviations and prosigns explains these signs.

How the Message Travels

A radiogram travels through nets at several levels. The ARRL says on its NTS page that the system is made up of operators trained in traffic handling who take part in nets at the local, section, region and area levels every day of the year. A message that starts in one town is passed to a local or section net, then to a higher-level net that carries traffic between regions, and then back down to the level that serves the destination. Finally, a volunteer delivers it by telephone, email, text message or in person. Our guide to running a ham radio net shows how a net control station keeps this organised, and our article on ARES and RACES explains how emergency groups connect with traffic nets.

Traffic handling is also a practical skill for digital modes. Modern systems such as the one described in our article on Winlink over HF can move messages by email over radio, but the discipline of clear, accurate formal messages carries across to those systems.

Is Traffic Handling Still Relevant?

The ARRL is frank about the current situation. Its NTS page notes that the spread of low-cost and free telephone calls, text messaging and the web means the general public has many alternatives to traditional radiograms, and much of today’s NTS traffic is simply between amateurs, such as welcome messages and licence expiration notices. It also says that there are serious questions about the accuracy and reliability of the networks and that some public agencies have never heard of the NTS or have created their own backup messaging systems. For that reason, the ARRL describes a modernisation effort called NTS 2.0, with training materials in a modern format. The skill remains useful, because it teaches accuracy, discipline and the habit of verifying what you copy, and these are valuable when ordinary communications fail.

How to Get Started

1. Download the current forms and guides. The ARRL provides the radiogram form, the handling instruction list and the NTS manual on its pages.
2. Listen to a traffic net. Many sections run daily nets. Listen for a few days, and note how the net control station calls for traffic and how operators pass it.
3. Practise with exercise messages. Use the word TEST before the precedence and mark the text as an exercise, and ask the group which runs the exercise whether the messages should be delivered.
4. Check in to a net. Offer to take a message. The first few times, ask a mentor to listen to your copy.
5. Keep a log. Record the messages you originate, relay and deliver, with the times and stations involved.

The Bottom Line

An ARRL radiogram is a formal message with a fixed order: a preamble with message number, precedence, station of origin, check, place of origin and date, then the address, the text of about 25 words or fewer, and the signature. The check counts the word groups, the precedence tells operators what to handle first, and optional HX codes give delivery instructions. Whether you use it for a real health and welfare message or for practice in a net, learning the format builds the accuracy that serves every other part of amateur radio.

Frequently Asked Questions

What is an ARRL radiogram?

It is a formal written message in a standard format that is passed by amateur radio operators through traffic nets until it reaches the person it is addressed to. The system that carries it is the National Traffic System.

What is the check in a radiogram?

The check is the number of word groups in the text. The receiving operator counts the groups they copied and compares them with the check, which shows whether anything was missed or added.

How long can the text be?

The text is usually limited to 25 words or fewer. It is divided into groups, five or ten to a line, so that counting is easy.

What do the precedence letters mean?

Emergency is spelled out and means a life-and-death situation. P stands for priority, W for welfare, C for certified and R for routine. Higher precedence messages are handled first.

Can I send a radiogram for someone who is not a ham?

In the United States, amateur operators can send and deliver radiograms on behalf of members of the public, which is third-party traffic that FCC rules specifically permit. Rules differ by country, so check your own regulations.

Do I need a licence to learn traffic handling?

You need an amateur radio licence to transmit on the air. Anyone can study the format and listen to traffic nets, and many operators practise on exercise messages before they handle real traffic.