Coast station VKW · 500 kc/s · the 0200 watch
Rhythm keyed into the static.
A radio room at sea, two in the morning. Hold the key — press anywhere on the console, or hold the spacebar — and a carrier lights the band: your dits and dahs scroll down the waterfall among the drifting noise, and the decoder reads them back as text. It never learns letters. It measures your hand's own timing, and either your rhythm survives the static or it doesn't.
01 · The decoder
The measure of a hand
Everything is one number: the unit. A dit lasts one unit — 60 ms at 20 words per minute. A dah lasts three. One unit of silence sits inside a letter, three end it, seven end a word. That is the entire alphabet: two mark lengths and three silences.
Speed is calibrated on the word PARIS — exactly 50 units including its trailing gap — so WPM = 1200 ÷ dit-length in ms. The decoder re-estimates the unit from every mark you send: slow down mid-word and it slows with you, from 5 to 46 WPM. It follows the fist, not the schedule.
THE SILENCES ARE PART OF THE LETTER
RED SECTORS AT H+15 AND H+45 · THREE MINUTES
SILENCE PERIOD — EARS ONLY02 · The watch
Three minutes of silence
Twice an hour, the whole band held its breath. From h+15 to h+18 and h+45 to h+48, every station on 500 kc/s stopped sending — three minutes, ears only — so that a weak SOS buried under the night's traffic could surface. The red sectors on the wheelhouse clock told the operator when to put the key down and listen.
That is the whole discipline of this room in one object: the channel belongs to whoever needs it most, and silence is enforced with the same precision as the marks. If the ship's clock beside you enters a red sector, the tag below the dial lights. Put the key down. Listen.