Traduction anglaise.
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.
This mode is included into the software MULTIPSK by Patrick F6CTE, there is the description of this mode and its variants as well as the specifications coming from his software :
Click on the copy of the screen in order to listen to the corresponding audio signal.
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)