Telegraph Simulator

How to use

1. 1

   The key is ready: Straight key, with the Telegraph sounder on.

2. 2

   Press and hold the key on the screen, or click the key area and use Space or Ctrl. A short press is a dot, a long one a dash. On a phone, tap and hold with one finger.

3. 3

   Listen: the sounder clicks when you press and clacks when you let go. The time between the two is the dot or dash.

4. 4

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

5. 5

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

6. 6

   Press Play back to hear your sending on the sounder, or save it as MP3 or WAV.

What it does

It is an online Morse code telegraph machine: a straight key wired to a telegraph sounder, played from the keyboard, the mouse, a touch screen or a real key. Switch Sound to Tone for the beep of radio Morse, or the tabs to paddles and a cootie key; the full Morse code simulator explains every key type.

• Reads your timing. 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, plays it with Hear it, and checks what you send.

How it works

A telegraph sounder has no tone. On a wire telegraph, the line current pulled an iron armature down onto its stop with a click, and it lifted back with a clack when the current stopped. Operators read the time between the two: a short gap is a dot, a long one a dash (Wikipedia: Telegraph sounder). This Morse code telegraph simulator plays a sharp click when you press and a softer, lower one when you let go, so you hear your timing the way an operator did.

Timing follows ITU-R M.1677-1: a dot is one unit and 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. At first a press longer than two units of the set speed reads as a dash; once your presses form a short group and a long group, the line between them follows you.

The code is International Morse. American telegraph lines used American (Railroad) Morse, with spaced letters such as O (. .) and a long dash for L; hear it on the sounder clips of Morse code sound and read it on American Morse code.

The telegraph it simulates

A telegraph line joined a key, a battery and a sounder at each office. Pressing the key closed the circuit and sent current down the line for as long as it was held; releasing it opened the circuit (Wikipedia: Telegraph key). Here the key is your Space bar or the screen, and the sounder is your speaker. For the key, the sounder, the register and the relay in full, read how the Morse telegraph worked.

Examples

Send STOP at 15 WPM (one unit is 80 ms):

With three gaps of 3 units between the letters (720 ms), STOP takes 39 units: 3,120 ms. Send it here and the Dot and Dash readouts show how close you came to 80 and 240 ms.

Trust and limits