<?color><?param0100,0100,0100>When Rik first outlined his idea of visual CW with dots and dashes the same length but on different frequencies, and with no gaps between the elements, I was not at all enthusiastic.<br><br>However, having seen it on a JPEG and having done some sums I think it is a really useful improvement on what we use now.<br><br>In order not to confuse the two modes, I will refer to extremely slow Morse as QRSs and the ON7YD system as VCW (visual CW, because it can only be decoded visually).<br><br>Positive points are:<br><br>For the same element length (same as dot length using Morse) a VCW contact will take about one-third of the time of a QRSs QSO. This can mean a saving of 30 minutes! The signal to noise is the same as QRSs as the dot length is the limiting factor.<br><br>Increasing the element length by three (effectively making the elements the same length as QRSs dashes), a 4dB improvement in signal/noise is achievable, provided the averagi ng control on Spectrogram is increased. But the QSO will be the same length as a QRSs contact is now.<br><br>It is very easy to read by eye - I showed a sample text to a licensed colleague without explaining what it was all about, or even that it was a sort of Morse, and he read it immediately.<br><br>It lends itself very well to a further improvement by synchronising transmit and receive timeslots.<br><br>Since each element is the same length, it lends itself well to being decoded by machine if required.<br><br>It will coexist well with QRSs (though I am sure it will supercede it).<br><br><br>Negative points are:<br><br>Additional text must be sent at the start to show the element length (because there are no gaps between consecutive dots or dashes in a letter) and dot and dash frequencies. This is easily achieved by sending the conventional commercial message start of CT (dah-di- dah-di-dah).<br><br>Since it cannot possibly be read by ear, normal CW callsigns must be used in each over for licensing and general courtesy.<br><br>A method must be devised to produce FSK of a few Hz.<br><br>It cannot be driven with a conventional keyer (as these have inter- element spaces). You must use a computer program. Rik will modify QRS soon.<br><br>The duty cycle goes from about 50 per cent with QRSs to 85 per cent or so for VCW so there may be heat dissipation issues. However, QSOs can be shorter.<br><br>It occupies a little more spectrum as two frequencies are used, but each frequency is copied in a sub-Hertz bandwidth so that shouldn't worry anyone.<br><br>------------------<br><br>I will post Rik's JPEG on my web site this evening so anyone who doesn't know what I'm talking about can see for themselves.<br><br>In my view, this is a major breakthrough in the use of extremely slow CW and DSP.<br><br><br><br><br><br><br><pre> Mike, G3XDV (IO91VT) http://www.dennison.demon.co.uk/activity.htm
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