Rik Strobbe wrote:
> Everybody who is involved in extreme narrowband mode such as QRSS and
> DFCW will confirm that signals that are 10 to 20dB below the 'normal CW'
> detectable level can still be copied and lead to a QSO. OK, it takes
> about 30 minutes or more but this time period is accepted for Meteor
> Scatter contact on VHF (I believe that the time limit for a valid QSO is
> 2 hours for MS). Nothing wrong with being a 'die hard' CW operator, but
> that is no reason for neglecting the fact that extreme narrowband modes
> are superior to 'normal speed' CW when it comes to signal to noise
> ratio. Both theory and practise proves this.
G3KEV replied:
Tell me Rik, why is there no qrss(LMCW) when the band is noisy like lots
of qrn/static about.
My ANSWER after monitoring and experimentation with
spectran is that the qrn chops the long dashes and you cannot
be sure if it was lots of dots.
On the contrary, I find that the advantage of QRSS is even greater
under heavy QRN - it's often the only mode that is viable in the
summer. Static crashes are usually much shorter than the dot
period and it is much easier to watch the bright white lines of static
than to listen to QRN. I cannot vouch for Spectran, but
Spectrogram works well under these conditions.
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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