Morse code simulator

1. 1

   Pick a key: Straight key, Paddles (iambic) or Cootie.

2. 2

   Press and hold the button on the screen, or click the key area and use Space or Ctrl (Z and X for paddles). A short press is a dot, a long one a dash. On a phone, tap and hold with one finger: a quick tap is a dot, a longer hold a dash.

3. 3

   With Paddles, [ and ] or the arrow keys work too, and Mode (A or B) and Swap paddles sit beside the practice choice. Esc clears what you sent.

4. 4

   Pick a sound: Tone, like a radio, or Telegraph sounder, the click-clack of a telegraph line.

5. 5

   Pause for a letter, and a little longer for a word. The code and the letters appear as you send; Backspace deletes a letter.

6. 6

   For practice, choose Send this word, press Hear it, then send it back. A right word offers the next one.

7. 7

   Press Play back to hear what you keyed, exactly as you timed it, or save it as MP3 or WAV.

• Reads your timing, not a threshold. It starts from the speed you set, then follows your own dots and dashes once they form two groups. Nothing to tune.

• Shows how you send. Hold and pause meters mark the dot, dash, letter and word lengths; under them, your average dot and dash in milliseconds, your speed, and a timing score out of 100.

• Practice with a goal. Send this word gives a common word with its code and checks what you send; the letters you send there count toward the daily goal and streak.

• Hear yourself. Play back replays your sending as you keyed it, and MP3 or WAV saves it.

• A chart at hand. Code chart opens the letters and numbers under the key.

New to the code? Learn the letters by ear first with the Koch method course, or pick another trainer in Practice.

Timing follows ITU-R M.1677-1: a dot is one unit, a dash three; the gap inside a letter is one unit, between letters three, between words seven. Speed is counted with the word PARIS, so one unit lasts 1,200 ÷ WPM milliseconds.

The simulator reads each press against that rule. At first, a press longer than two units of the set speed is a dash, so one long press reads as T. Once your presses form a short group and a long group, the line between them follows you.

A pause of three of your units ends a letter and seven a word; once your own gaps form groups, the breaks follow your spacing. In Send this word, a pause that could go either way is read the way that fits the word.

The timing score compares your average dash with three dots: 100 minus the miss in percent. A 2.4 to 1 ratio is a 20% miss, so 80 / 100.

The keys it simulates

• Straight key. The classic telegraph key: a lever with a knob that closes a contact while you hold it down, so you time every dot and dash yourself (Wikipedia: Telegraph key).

• Telegraph sounder. The receiver of a wire telegraph. The line current pulls an iron armature down with a click, and a counterweight lifts it back with a clack; operators read the time between the two (Wikipedia: Telegraph sounder). The Telegraph sounder sound plays a sharp click on key down and a softer, lower one on key up. To turn typed text into sounder audio, use the Morse code generator.

• Paddles (iambic). A dit paddle and a dah paddle; the keyer times each element and adds one unit of space. Squeezing both alternates dits and dahs. Paddles come single-lever or dual-lever; this simulator plays dual-lever (iambic) paddles, and pressing one side at a time sends as a single lever would. Radio amateurs call Morse sent by radio CW, for continuous wave.

• Cootie key. A sideswiper: one lever swung left or right, with a contact on each side and a spring that returns it to the middle. Either side keys, so you alternate sides and time each element yourself, as on a straight key.

A worked score: you send CQ (-.-. --.-) and your dots average 100 ms and your dashes 240 ms. The ratio is 2.4 to 1, so the score reads 80 / 100 with “Your dashes are short: hold them for about three dots.”

Dashes of 330 ms give 3.3 to 1 and 90 / 100; dashes of 400 ms give 4 to 1 and 67 / 100. Speed shows 13 WPM, read from your own timing: the unit is the average of the dot and a third of the dash, 90 ms.