Hellschreiber (Feld Hell)
An old method that 'paints' text as a picture, dot by dot, so your eye does the decoding.
ModeHellschreiber
FamilyText as a picture
Audio example12 s
What does it sound like?
Plate 24Text as a picture
A rough, rasping buzz with a steady rhythm.
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 marksText drawn as a picture on the waterfallFeld Hell: 122.5 dots per second
Who uses it?
Amateur radio enthusiasts (the Feld Hell Club holds regular activity sessions).
Where and when can I hear it?
Various ham frequencies.
Easily confused with
- FSK Hell: FSK Hell uses two tones
- Morse code (CW): Morse is a single keyed tone in dots and dashes