MT63
A very robust text mode spreading data across 64 tones, designed to survive noise and interference.
ModeMT63
FamilyMultitone data
Audio example12 s
What does it sound like?
Plate 38Multitone data
A dense, steady rushing sound, like wind with a musical texture.
0 Hz1,0002,0003,000 Hz
12-second example. A clean example made by our own signal generator; signals on the air usually sound noisier.
Field marks64 tones at onceAbout 1 kHz wide (MT63-1K)Sounds like a dense hiss
Who uses it?
Amateur radio operators, especially emergency-communications groups.
Where and when can I hear it?
Various ham frequencies on HF and VHF.
Easily confused with
- STANAG 4285 (NATO modem): STANAG 4285 is a single, wider carrier
- Digital Radio Mondiale (DRM): DRM is about 10 kHz wide on broadcast bands