What Is the CT Prosign in Morse Code?
CT (also written KA) is the prosign for start of message / attention. The letters C and T (or K and A) are sent run-together as one 5-signal symbol.
When you search for “ct prosign in morse code”, “morse code for ct prosign”, or “CT in morse code”, the answer is the same ITU-standard pattern: -.-.-. Other common names for this prosign include KA, start of message, attention, copy this.
When to Use the CT Prosign
Sent at the very beginning of a formal message or net call to alert all listeners that an official transmission is about to start. Often followed by the destination callsign.
Practice: What Is the Morse Code for the CT Prosign?
Select the correct Morse code for the ct prosign (CT):
How to Tap the CT Prosign in Morse Code
To transmit the ct prosign (-.-.-), use this sequence:
ITU Timing Rules
- Dot (·) = 1 unit
- Dash (−) = 3 units (3× longer)
- Signal gap = 1 unit
- Letter gap = 3 units
- Word gap = 7 units
Timing Reference Table
| Speed | Dot | Dash | Letter gap | Word gap |
|---|---|---|---|---|
| 5 wpm | 240ms | 720ms | 720ms | 1680ms |
| 10 wpm | 120ms | 360ms | 360ms | 840ms |
| 17 wpm (this page) | 70ms | 210ms | 210ms | 490ms |
| 20 wpm | 60ms | 180ms | 180ms | 420ms |
How to Remember the CT Prosign in Morse Code
“Copy This” — alternating long-short-long-short-long, like a wake-up rhythm: ‘now-pay-att-en-tion.’
Frequently Asked Questions — CT Prosign in Morse Code
The ct prosign (CT) in Morse code is -.-.- (2 dots, 3 dashes). It’s the standard ITU code used worldwide.
The Morse code for the ct prosign is -.-.-. Tap the sequence as: dash, dot, dash, dot, dash, with a one-unit gap between each signal.
To send the ct prosign: long press, then short tap, then long press, then short tap, then long press. Keep one unit of silence between each signal and three units between this character and the next.
The ct prosign uses 5 signals total: 2 dots and 3 dashes.
Sent at the very beginning of a formal message or net call to alert all listeners that an official transmission is about to start. Often followed by the destination callsign.
Yes — -.-.- is defined by the ITU (International Telecommunication Union) Recommendation M.1677 and is used worldwide for the ct prosign.
Related Morse Code Prosigns
Other prosigns commonly used alongside the ct prosign: