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Say Again?

Real VHF calls are rarely clear. Listen to twenty transmissions of phonetic letters and radio numbers through the kind of interference you meet at sea, from engine noise to another boat talking over the call. Four levels, twelve calls each. Turn your sound on.

How the game works

Pick a level. Deckhand starts with short calls on a clear channel; Watchkeeper adds call signs, channels, fading, engine noise and wind; Skipper brings MMSI numbers, spelled boat names, a breaking signal and a whistle, with only one repeat; Coastguard throws everything at you, including another station talking over the call, and you type what you heard instead of picking it. Each round is twelve calls, and the channel gets worse as it goes. The interference falls differently on every play, so a repeat can fill the gap, just as asking “say again” does on the radio. The wrong answers are near misses: one character changed, or two swapped.

The interference

Hiss:
a weak signal sinks into the radio's background noise. Turn the volume up, not the squelch. Opening the squelch lets more hiss in.
Crackle:
sharp clicks from static, lightning or a loose connection. Crackle is short: a missed character is usually next to one you heard clearly, so use the repeats.
Fading:
the signal swells and sinks as the other boat rolls or moves behind land. Listen hardest on the peaks, and fill the troughs from the repeat.
Breaking up:
the signal drops out completely for a word or two. If parts are missing, ask "say again all after" the last word you heard. Never guess a number.
Engine noise:
your own diesel rumbling under the cockpit. Throttle back, or take the call on a handset below or with the speaker close to your ear.
Wind:
gusts across the microphone or round your ears on deck. Turn your back to the wind and shelter the handset or speaker.
Whistle:
a tone from two transmitters on the same channel at once. The words are still under the tone. Concentrate on the start of each word.
Another station:
a second boat transmitting on top of the call. When two stations double, wait for the channel to clear, then ask for a repeat.

Why it matters

Call signs, MMSI numbers, positions and channel numbers are all passed letter by letter and digit by digit. Numbers are said the radio way, such as “tree”, “fife” and “niner”, so they cannot be mistaken in noise. If you miss part of a real call, say “say again”, or “say again all after” the last word you heard; never guess.

About the sound

The voice is your device’s own speech voice and the static is made in the browser, so nothing is downloaded and the voice may sound different on each device.

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