Sounder Style vs. CW Tone
Sounder Style
Sounder Style produces a short click when a Morse mark begins and a clack when it ends. The silence between those two events carries the length of the dot or dash. It is a lightweight browser simulation, not a recording of a physical telegraph instrument.
CW Tone
CW Tone uses a steady audio frequency for the full duration of each dot or dash. This is closer to the tone-based Morse practice used with modern radio and audio trainers.
How a Telegraph Key Sends Morse
A straight telegraph key works as a simple electrical switch. Pressing the lever closes the circuit and releasing it opens the circuit. A brief closure represents a dot, while a longer closure represents a dash. The timing between marks tells the receiver where one character ends and the next begins.
This browser simulator measures how long you hold the key rather than switching a physical telegraph circuit. At 20 WPM, for example, one Morse timing unit is 60 milliseconds. Auto threshold uses two timing units as the dividing point between a dot and dash.
Want to understand the physical hardware behind the simulator? Read the Morse Code Equipment guide for straight keys, paddles, keyers and practice setups.
What Is a Telegraph Sounder?
A telegraph sounder is a receiver that turns electrical line pulses into audible mechanical movement. Incoming current energizes electromagnets, moves a lever or armature, and creates a click; when the current changes again, the mechanism returns and produces the corresponding release sound. Operators learned to recognize Morse from the timing between those events.
The Sounder Style option on this page uses Web Audio to approximate that two-event rhythm. It does not claim to reproduce the exact tone, resonance or mechanics of a particular historical sounder.
Morse Key Timing
International Morse uses proportional timing rather than fixed millisecond values. A dot lasts one unit and a dash three units. The gap between parts of one character is one unit, the gap between characters is three units, and the gap between words is seven units.
| Element | Duration |
|---|---|
| Dot | 1 unit |
| Dash | 3 units |
| Inside-character gap | 1 unit |
| Character gap | 3 units |
| Word gap | 7 units |
The simulator calculates one unit as 1200 divided by the selected WPM. The Auto dash threshold is two units—the midpoint between an ideal one-unit dot and a three-unit dash.
How to Use the Morse Keyboard and Telegraph Key
Type with the Morse Keyboard
Open Morse Keyboard and type normally or use the on-screen keys. The tool converts each supported character to International Morse and can play the pattern as audio.
Send with the Telegraph Key
Open Telegraph Key and press the large key with a mouse or touchscreen, or hold the Spacebar. Release quickly for a dot and hold longer for a dash. The current character is decoded after a normal character-length pause.
Try Sounder Playback
Open Sounder Playback, enter a message, choose Sounder Style or CW Tone, and press Play. Sounder Style marks the beginning and end of each Morse signal with synthetic click-and-clack feedback instead of a continuous tone.
Frequently Asked Questions
What is a telegraph key simulator?
A telegraph key simulator measures how long you press a virtual key and interprets short presses as Morse dots and longer presses as dashes. This page supports Spacebar, mouse and touchscreen input and decodes the resulting International Morse in real time.
Can I use the Spacebar as a Morse key?
Yes. In Telegraph Key mode, press and hold the Spacebar to key a signal and release it to finish the mark. Spacebar keying is disabled while you are typing inside normal form controls so it does not interfere with page navigation.
How does the simulator decide between a dot and a dash?
In Auto mode, one Morse timing unit is calculated as 1200 divided by the selected WPM. The dash threshold is two units. A press shorter than that threshold is read as a dot; a press at or above it is read as a dash.
What is a telegraph sounder?
A telegraph sounder is a receiving device that converts electrical pulses into mechanical clicks. Traditional sounders used electromagnets and a moving armature, allowing trained operators to recognize Morse from the timing of the resulting sounds.
What is the difference between Sounder Style and CW Tone?
Sounder Style creates a click when a mark begins and a clack when it ends, with silence between them. CW Tone plays a continuous audio frequency for the full duration of each dot or dash.
Is Sounder Style an authentic historical sounder recording?
No. It is a lightweight Web Audio simulation designed to reproduce the click-and-clack timing idea without loading external recordings. Real telegraph sounders differ in mechanics, resonance and tone.
Does this page use American or International Morse?
The keyboard, telegraph key and Sounder Playback modes use modern International Morse Code. Historical U.S. landline telegraphy also used American Morse, which has different character and timing rules.
What WPM should I choose?
Choose a speed that lets you send clean, repeatable timing. WPM on this page controls the timing reference used for dots, dashes and automatic decoding; you can increase it as your keying becomes more consistent.
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