[Lf] LF: qrss]

[Andre' Kesteloot]

'Geri' Kinzel, DK8KW wrote:

> Mal,
>
> you and me are putting good signals in the air, for various reasons.
> However, there are several others who are far below the noise level. If you
> have look on my homepage (http:/www.qru.de/signals.htm), you will see a
> graph, that shows the signal strenght in dBu vs. the distance in km. Most
> of the German stations for example suffer from both: low power (20 Watt due
> to the German regulations ... ) and bad antennas. The noise level at my qth
> typically is in the -110 dBu range, sometimes moch worse (-90 to -100 dBu):
> I had several contacts with stations on 136 kHz, that I could not hear
> aurally, because their signals were 10 to 20 db below the current noise
> level. With an "M", we still were able to manage a good QSO. Also on my
> page you find a list of stations that I have worked so far on LF
> (http://www.qru.de/stnhrd.htm). In the column "max . signal strength" you
> find several stations without a signal report. Most of those stations were
> far below the noise level, but readable in Slow-CW. For example, I would
> not have been able to contact IK5ZPV in normal CW.
>
> I made some experiement, injecting a signal generator into the normal
> day-to-day noise. With my 25+ years of CW experiencs, I believe I can hear
> CW signals well below the noise level. But with spectrogram in Slow-CW, I
> am able to see (and read) signals that are 10 to 20 dB the lowest level my
> ear is even able to detect the signal. Maybe it is a matter of the
> Spectrogram settings.
>
> I am sure, if we ever have a successful 2-way transatlantic QSO, it will be
> in Slow CW!
>
> Best 73
>
> Geri, DK8KW (W1KW)
> homepage: http://www.qru.de
>
> "Longwave enthusiasts do it extremely slow!"