The staff of many large orienteering events use radios to facilitate communication over a large area. Proper use of the radios can make them a very valuable tool; improper or poor use can render them useless or have them condemned as an annoyance and a distraction.
Make sure each radio user knows how to turn on their radio and adjust the volume. Before setting out into the field, set each radio to the desired frequency/channel.
Some radios (FRS and others) have a “privacy” sub-channel, which also will need to be set. This sub-channel acts as a filter, blocking transmissions from radios that are not set to the same sub-channel. Setting a sub-channel of 0 is the same as allowing all transmissions on the frequency/channel to be heard. However, a radio set to a sub-channel of 0 can not be heard by a radio set to any non-zero sub-channel.
When speaking, hold the radio close – really close! - to your mouth. Rarely is there ever a need to shout into it. Radios have amplifiers and volume controls – speak as you would to a person standing near you and let the electronics take care of the rest. It is more useful to speak distinctly than it is to speak loudly. In a noisy setting, it might be necessary to speak up, but that's about the only time.
To transmit, press the key/button, wait a half second or so, and then start talking. When done, wait another half second before releasing the key/button.
This might seem obvious, but – radios are not very effective when turned off. Turn them on and test them before setting out for the day.
Listen before transmitting. Make sure that you are not interrupting someone else's conversation. Think before transmitting. Know what you are going to say and to whom you wish to speak.
To initiate a conversation with someone, call them using the pattern “you, this is me”, e.g., “Abby Gail, this is Betty Sue”. To respond, simply reply “this is me”, e.g., “This is Betty Sue”. If it is desired to talk to anyone at, say, the finish, then call “Finish, this is Charlie Horse”. The staff member at the finish could respond “This is Deputy Dan at the Finish, go ahead”.
In general, do not include anything in your first call. It is better to know that your audience is listening before asking something complicated. A short query such as “Eager Beaver, this is Frenzied Fran. Where are you?” is OK, but expect to repeat the question if your intended recipient doesn't respond on the first call.
Broadcasts (transmissions to anyone who answers instead of to a specific person) should be of the form “This is Gullible Gus. Does anyone know where the bags for the snipe hunt are?” Replies should include the identity of the respondent: “Gus, this is Hysterical Henrietta. The bags are next to the cage with the Sidehill Dodgers.”
There are terms and phrases that make radio communication effective, and those which are better left to the movies and TV shows from whence they came. What follows is borrowed from the rules for aircraft communication, where there is premium on efficiency and conciseness – and severe consequences for misunderstanding.
“Acknowledge” is a request to let the speaker know that their message has been received.
“I say again” means that the message will now be repeated, either for emphasis or to ensure comprehension.
“Affirmative” and “negative” are fancy ways of saying “yes” and “no”. “10-4” is used by those who either don't know how to say “OK” or “yes” or are merely pretentious.
“Roger” means “I have received your transmission and understand it”. Should not be used in response to a question expecting a yes or no answer. For counter-examples, watch “Airplane” and “Airplane II”.
“Wilco” means “I have received your request and will comply with it”.
“Over” is used at the end of a transmission to indicate that the speaker is done talking and now it's the other party's turn. A response is expected.
“Out” is used by the originating party (the person who started the conversation) to indicate that the conversation is concluded. No response is expected. It is nonsensical to say “over and out”.
“Say again” is a request for the other party to repeat their previous transmission. This can be abbreviated to just the information needed: “say again their name”. Do not use “repeat” for this.
For clarity, numeric values should be spelled out - “15” and “50” sound a lot alike, but “one five” and “five zero” do not. Do not say “oh” in place of “zero”. Words can be spelled phonetically, ideally with a standard phonetic alphabet. Avoid something like “they are on KP duty, that is 'K' as in 'know' and 'P' as in 'pneumonia'”.
Radio transmission and reception is affected by the locations of the respective radios and what is between them. The best location is on top of a hill with no trees near by. Among the worst is inside a vehicle in an underground parking garage (or tunnel). When communication is poor, try moving around a bit while listening to the other party transmit. If necessary, transmit “in the blind” on the hope that the other party can hear you.
At a large meet, it might be useful to use several frequencies/channels – one for general meet administration, another to support announcing (i.e., from a warning control). Just remember who is on what frequency.
Remember that in all communications, what matters is what the other person hears. What you say and how you say it will influence what is heard – choose your words carefully!
Radio communications are not private. It is essentially impossible to know who is listening to your conversation – others might have radios tuned to the frequency/channel you are using, or they might be within earshot of someone else's radio. Take care when discussing sensitive topics – marker placement, safety issues, or personnel matters. If necessary, arrange to meet face to face.
Finally, don't use the radio if you don't have to or don't have anything important to say. When you transmit, everyone has to listen to see if your message is for them. Frivolous transmissions waste everyone's time and energy. Use the radio sparingly.