Listening is the most important skill in radio operating. It is a skill that allows us to ensure that a transmitting station is heard, and also allows us to avoid introducing interference.

Most of us operate a transceiver, a radio with a built-in transmitter, receiver and transmit/receive antenna switch that is controlled by a push-to-talk switch. By nature, a transceiver operates in a half-duplex mode where you can talk or listen at any given time, but cannot simultaneously talk and listen at the same time. This means that we cannot interact as we do with face-to-face conversation, where unencumbered interjection and interruption are possible. Half-duplex operation requires that any interjection or interruption occur in a manner that is synchronized with the conversation.

If you are operating on a repeater, synchronizing an interruption to the conversation requires listening to the squelch decay noise of the repeater receiver to determine when a station has completed transmission. When a station stops transmitting, the repeater transmitter will remain keyed for a short period of time (usually from one to three seconds), and you can hear a short burst of noise as the repeater receiver squelch circuit charges a capacitor to mute, or squelch the noise. When the repeater transmitter drops, you will also hear this same kind of noise burst as your own receiver squelch circuit charges a capacitor to mute, or squelch the noise at your own receiver. The time period from the first noise burst to the second noise burst defines the repeater squelch tail. Any interjection or interruption (i.e. breaking into the conversation) should occur during the squelch tail, as delimited by the two noise bursts. Do not wait for the repeater transmitter to drop as your transmission will likely be simultaneous to a participant already in the conversation. All stations already participating should wait until the termination of the squelch tail, as indicated by the second noise burst, before initiating transmission. If a station initiates transmission during the squelch tail, all other stations should listen and wait for the squelch tail to drop before the next station in turn, or the station to which the interjection is directed, responds to the transmission.

This protocol essentially defines a listening protocol that best ensures against simultaneous transmission and reduces interference on the repeater.

When operating on a Directed NET, and when the NET Control Station (NCS), not calling stations from a roster of participating stations, asks for check-ins, adherence to the following procedure will help NET operations by reducing the amount of interference generated by simultaneous transmissions from two or more stations.

1. Listen and wait for the NET Control Station to request that stations check-in. Listen carefully for this request as there may be geographical limitations to the request. If the request from the NET Control Station includes criteria that excludes your station, do not initiate transmission and continue to listen.
2. Pause and listen, proceed to step 3.
3. If a station was heard, proceed to step 4.
   If no station was heard, proceed to step 5.
4. Wait until the transmitting station completes their transmission and return to step 3.
5. Key your transmitter and proceed to step 6.
6. Speak THIS IS and proceed to step 7.
7. Un-key your transmitter and proceed to step 8.
8. Listen to determine if another station is transmitting.
9. If you hear another station transmitting, proceed to step 10.
   If you do not hear another station not transmitting, proceed to step 11.
10. Listen and wait for the transmitting station to complete their transmission and then return to step 5.
11. Key your transmitter and proceed to step 12.
12. Speak your call-sign and proceed to step 13.
13. Unkey your transmitter and proceed to step 14.
14. Listen for further instructions from the NET Control Station.

The purpose of this procedure is to allow each station to determine if they are transmitting simultaneously to one or more other stations and to stop transmitting in favor of yielding to the other station in the interest of reducing interference. The benefit is that this allows the NET Control Station to more easily identify the stations checking in and will greatly reduce the number of requests that the NET Control Station needs to make to complete the check-in process, and allows the NET to progress more efficiently.

A decision tree that depicts this process is shown below.

The NET Control Station will pause to allow for check-in stations to identify themselves. You can help alleviate interference by not attempting to be the first station to check-in, but rather, attempt to be the last station to check-in.

Note that this procedure further builds on the principle of the importance of listening.

Simplex operations are an important resource for ARES operations. Simplex requires a different set of procedures than repeater operations.

With repeater operation, we experience mostly full-quieting signals, and are often able to operate with a tight squelch setting. With simplex operations, we must be able to interact with both strong and weak signals. The following set of recommended practices are intended to allow NET operations to obtain the highest level of success possible when simple operations are required:

• The NET Control Station should solicit, from the pool of available operators, mobile stations that can travel to a local hilltop or mountain top location to act as a relay station.
• Stations that have a mobile capability, and are able to travel to a higher location to act as a relay station should respond affirmatively to a request from the NET Control Station for mobile relay operators.
• With simplex operations, many stations may have signals with poor receiver quieting. All stations should operate with their squelch gate adjusted so that a weak signal can open the squelch.
• All stations should exercise a brief pause between transmissions. During this pause, listen for weak stations.
• NET Control Stations should periodically request all stations stand-by and listen for weak stations.
• The NET Control Station may designate that a relay station operate as an Alternate NET Control Station. Alternate NET Control Station operators may, at the direction of the NET Control Station, be directed to make a NET CALL where the content of the call is indicated in the request from the NET Control Station.
• If you hear a weak station and that station is not being heard by the NET Control Station, wait for a pause in NET traffic and then call the NET Control Station to volunteer relay station services. Your call to the NET Control Station should use the following procedure:
  1. Listen and wait for a pause in NET activity.
  2. When no other station is transmitting, key your transmitter.
  3. Speak: Relay <CALL-SIGN>.
  4. Un-key your transmitter.
  5. Listen for instructions from the NET Control Stations
• Do not occupy the simplex channel with unnecessary conversation, under the assumption that no other station is attempting to communicate.

With simplex operation, a strong signal will capture a receiver when a weak signal is being transmitted simultaneously. It is important to realize that your station may not be hearing the weak station, and as such, the frequency may actually be in use. A focus on listening and ensuring that you enable weak signals to participate in NET operations.

We often hear the word bandwidth associated with how much spectrum is being occupied by a signal. In this case, bandwidth refers to the amount of traffic that can be handled in a given period of time.

Any NET has a fixed upper limit of the quantity of traffic that can be handled. Improper operating practices can degrade this upper limit, through the act of consuming too much time, resulting in reduce NET effectiveness and reduced NET capability.

The following operating practices are intended to prevent operations from degrading NET operations by avoiding excessive bandwidth consumption:

• Avoid over-use of the phonetic alphabet. Phonetics require significantly higher bandwidth than plain language, and should only be used when required to clarify information when signal quality mandates their use, or in a structured traffic environment where standard traffic procedures mandate their use.
  
  For NET operations conducted with FM emissions, and where full-quieting signals are the norm, phonetics are rarely required.
  
  There are cases where NET operations intend to build a proficiency in the use of phonetics. In such cases, instructions that are provided by the NET Control Station take precedence over this rule.
• Phonetics should not be used when responding to a roster based roll-call unless mandated by instructions from the NET Control Station.
• Avoid conveying redundant or unnecessary information. A read-back of traffic content may be appropriate to verify the accuracy of information, but usually a full read-back is not necessary when other metrics, such as a word count, are used to assess accuracy. The two stations exchanging information should assess what tools to employ to ensure accuracy.
  
  However, information that unnecessarily consumes bandwidth without either providing necessary information, and does not support the goals of the NET, should be avoided unless mandated by instructions from the NET Control Station.
  
  
• Always pass elements of required traffic in the order stated in instructions provided by the NET Control Station. The NET Control Station is usually using a check-list, with a fixed ordering defined for the collection of information. When participating stations provide information in an order other than that stipulated in the instructions received from the NET Control Station, this leads to errors in recording data, and requests for repeated information. Any request for repeated information consumes excessive bandwidth, and can usually be avoided by adhering to not just the content of information requested by the NET Control Station, but the order of information contained in that request.
• Do not interrupt the structured portion of NET operations with non-germain questions or comments. If you have a non-germain question or comment, request the NET Control Station call you after the formally structured portion of the NET operations have been completed. If you are a NET Control Station, and receive a request to handle traffic that is not germain to the structure and purpose of the NET, ask that the station hold that traffic until the end of the structured portion of the NET.
  
  It is perfectly acceptable to make a request to the NET Control Operator handle off-topic traffic at the end of NET operations. Such a request will not introduce a delay in completing those tasks for which the NET has been created to fulfill.
• As a NET Control Station, or a NET participant, be cognizant of the NET schedule, including the operational period of the NET, as specified by the scheduled start and end of NET operations.
  
  This is especially important when the NET is conducted using resources that employ automated scheduling, such as a linked repeater network, where, should NET operations run over-time, those resources may be automatically demobilized prior to the conclusion of NET operations.
  
  In cases where automation is used to connect repeaters to form a network, enabling a larger population of stations to participate, it is important that NET operations are completed before automation disconnects the network at the scheduled end of net time. Stations that rely upon the network will be cut-off from all NET activities should the NET run over-time beyond the time period where automation disables the repeater network. All NET participants can make a positive contribution, using good operating practices, to ensure that NET activites are completed prior automation kicking in and disabling NET infrastructure.
• When participating in a NET where a roster based roll-call is conducted by the NET Control Station, please be on-time. If you miss your call and have to check-in as a late or missed station, you will consume significantly more bandwidth than being on-time.
• Do not unnecessarily repeat dialog. For example, saying ROGER once is sufficient. Saying ROGER multiple times does not usually provide any additional utility relative to a single instance.
• Use language that is clear and concise. Avoid use of codes, lingo and slang. All operators are encouraged to become familiar with the Incident Command System. In order to support interoperability with served agencies, to the greatest extent possible, all communications should use plain language. This policy is heavily advocated in the Incident Command Courses that are available through FEMA (FEMA courses for ICS-100, ICS-700, ICS-800 and ICS-200 are highly recommended, and available through the Training menu on this web-site).
• When passing traffic that must be written down by the operator at the receiving station, do not pass the traffic at a speed that is faster than you yourself can write. It is a good idea to write the traffic as your pass it to ensure that the traffic is not being passed faster than it can be written. Implementing the proper speed when passing traffic avoids requests to repeat portions, or the entire content of the message being passed.
• Arrive to the NET on-time so that you will be able to hear the NET preamble when it is conveyed to participants by the NET Control Station. The preamble provides instructions to participants as to the structure of the NET, the order of and content of information participants are to convey to the NET Control Station by participating stations, and the schedule by which the NET will progress.
  
  Often, late arriving participants will not hear the preamble and then provide insufficient, incorrect, or improperly ordered information when checking in. This results in the NET Control Station having to provide instruction, request clarification, or request additional information in response to an improper check-in procedure.
• When participating in a training or exercise NET, participants should develop a habit of recording the order of stations checking into the NET. When the NET progresses to where participants are performing the processes or procedures in service of the purpose of the NET, the participant will often receive a message from the station prior to them in the check-in list, and will then be required to send a message to the next station in the check-in list. Failure to record this information can result in a break-down in NET communications. The NET preamble should include instructions as appropriate to this recommendation.

In essence, the poor use of time is the enemy of effective NET operations. The poor use of time can destroy the effectiveness of the NET. Poor operating practices by a single station can usually be absorbed without significant impact to NET operations. However, when several stations use poor operating practices, the ability of the NET to absorb the impact is diminished and the NET can become inefficient. All operators should adopt operating practices that allow the NET to operate efficiently. NET Control Stations should be familiar with proper operating practices, and, if necessary, use their authority, as the NET Control Station operator, to enforce proper operating practices by exercising control over the NET and conveying proper instructions to participating NET operators.

The following examples illustrate a NET that consumes minimal bandwidth and a NET that consumes excessive bandwith. For both NETs, the NET preamble instructed participants to indicate traffic status first and power source second.

Emergency Communications often involves the use of alternate power sources. This may include use of resources that may not be immediately renewable. This can include generators that are dependent upon fuel, batteries that are dependent upon a charging source, and even solar panels that may be ineffective when sun light is not available. In order to conserve these critical resources so that they are available to support the handling of critical traffic, these resources should not be drawn down by handling non-critical, or non-germain traffic.

Transmitting always draws down these consumables at a faster rate than receiving. Battery life will be reduced by use of the transmitter. An HF station that is powered by a generator will see the generator load increase during transmit periods, resulting in the generator increasing power to handle the increased load and further resulting in increased fuel consumption.

Under emergency communications conditions, please do not engage participating stations in idle or curious conversation that is not directly relevant to supporting that station in handling traffic directly related to situation that has created emergency communications conditions. Causing the EMCOMM station to draw down resources may result in an inability to communicate at a later time, when communications is absolutely critical to life, safety or property.

The time to satisfy your curiosity is after the emergency event has passed, not during the emergency event.

Because of Amateur Radio's close relationship to Emergency Communications and Public Service communications, it is vital that Amateur Radio operators are understood by those agencies and organizations that they serve. The day to day operating habits that we establish will prevail in NET operations, Emergency Communications or Public Service communications. The use of anything other than plain language serves only to cause a break-down in communications.

Federal Emergency Management Administration (FEMA) Incident Command System processes and procedures mandate that Plain Language be used in order to avoid confusion. Jargon, Slang, and Lingo are to be avoided. The following should be avoided and discouraged:

• CB Lingo
• 10-Codes
• Q-Signals, outside of an Amateur Radio Network Traffic System or Morse environment

For example, the word Handle is regularly used in the Citizens Band service to refer to an alias. The use of the word Handle to describe a given name is non-sensical, and is equivalent to saying my name is my alias. It is far better, and proper to say my name is Bob rather than saying my handle is Bob or the personal is Bob.

The use of the phrase got a copy? is also prevalent on Citizens Band radio. But what does it mean? Does it mean: Is anyone on frequency that can give me a signal report? Or, does it mean: Is there anyone on frequency that can render assistance? Or, does it mean: Is anyone on frequency? The phrase has been used in all three contexts but both the meaning and the urgency of the request are ambiguous.

In another example, and especially for those Amateur Radio operators that participate as radio operators in other services (e.g. MARS, USCG AUXILIARY HF CONTINGENCY COMMUNICATIONS, IDAHO SECURE NET, etc.) are well advised to avoid the use of Q-SIGNALS. Use SWITCHING in lieu of QSY, or other plain language descriptions in place of other Q-SIGNALS.

Without exception, it is always better to say what you mean using plain language. For example, if a signal report is desired, simply key the transmitter and ask: Is there anyone on frequency that can give me a signal report? Similarly, if assistance is needed, simply key the radio and make a general request for the type of assistance required, such as: Is there anyone on frequency who can call Idaho State Police to report a vehicle off the road? Clarity of expression will get you what you need.

The reason that adopting Plain Language is important to our normal day to day Amateur Radio operations is that our day-to-day operations are a form of training, and in an emergency, we fall back on our training. If operators get in the habit of using plain language, they will find that they can seamlessly integrate into the Incident Command System environment, and into other radio services.

There are many types of NETs. The following table provides a summary of several common types of NETs. It should be noted that NETs are not confined to these definitions. A NET always has a goal, and the processes and procedures for the NET are adopted specifically to fulfil the NET goal. This may include additional procedures that are not covered here, or even the combining of several types of NETs into a single hybrid-NET.

A NET should have a NET script, which is used by the NET Control Station to provide instructions to participants and to ensure that the NET flows in an orderly manner towards fulfilling the goals of the NET. The NET script may include the following items:

• An Introduction or announcement of the NET
• A NET preamble, consisting of
  • State the operational days/dates, NET start time, and scheduled end of NET
  • Stated purpose and/or goal for the NET
  • A description of NET schedule (i.e. the tasks and order of tasks to be accomplished during the NET)
  • A description of what information and the order of information that should be conveyed to the NET Control Station when a participating station is acknowledged by NET control during the station check-in process.
  • If automation is managing NET infrastructure, a statement to the participants regarding the need to complete NET operations within the automation time window and a disclosure of the automation time window limits may be prudent.
• A script by which the NET Control Station can perform NET Control Station duties in a controlled and consistent manner. The script should include instruction for each phase of the NET (e.g. emergency or priority traffic, announcements, member check-in, visitor check-in, late check-in, traffic, final late check-in, closing the NET.
• If any post-mortem NET reports are required, the instruction for these should be included in the NET script as instructions to the NET Control Station operator.

Again, these NET types and definitions are recommendations only. The NET administrator will determine the goal for the NET and establish processes and procedures that fulfill the goals of the NET. The purpose, process and procedures for the NET should be communicated to all NET participants during the NET preamble. Information contained within the NET preamble takes precedence over the NET definitions found here.