Morse is a digital mode because it can be easily decoded by a computer but it can be seen as a sort of non-digital code for Ham people who decode a Morse character no as a series of dashes and dots but as a particular “ music ”. That is why, in reading Morse, humans are better than programs.
Description :
Speed : currently 10 to 40 wpm (standard speed: 20 wpm)
Modulation : On-Off keying of an audio tone (currently between 500 and 800 Hz) or of a HF simple carrier but in that case, there must be a difference between reception and transmission frequencies,
Receive mode : indifferent (LSB or USB)
Character set : A..Z 0..9 ? = / + and some others signs more or less used (“ Varicode ” characters type)
A carriage return is transformed in space
Shape of pulse : rectangular
Bandwidth : up to about 100 Hz according to speed,
Demodulation : non coherent,
Synchronization: on reception of a dash or a point
Correction code: no
Convolution code: no
Interleaving : no
Pmean/Ppeak : 0.5 but very variable
Lowest S/N : the slower is the CW, the easier is the decoding (for example, one can reach -15 dB/-20 dB for a 20 wpm Morse decoded by a human being), this down to about 10 mpm (for humans)
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