On 15 Dec 2009 at 11:03, Stefan Schäfer wrote:
> If the "gain" or better said SNR between qrss30 and qrss3 is 10dB, so
> can I do a QSO to VK with 1W TX Power and an antenna efficiency of
> 1/1000 if I choose QRSS10000000000? That's a litte jokingly formulated
> but you know what I mean. In other words, where are the limitations of
> this rule?
This is certainly theoretically possible, but only if 'ground-wave'
is being used. If you are using sky-wave - as all intercontinental
QSOs have so far - you are limited by the length of time that the
path is open. Between UK and eastern US, this is a maximum of a few
hours, but often very much less, which is why the speed must be a
compromise between length of the 'opening' and the length to transmit
the information. This compromise usually result in using QRSS60.
Between Europe and VK/ZL any 'opening' is likely to be only a few
minutes making a two-way QSO extremely difficult.
> So, qsos could be done much faster if choosing 10x the
> power and stay in qrss3. The additional advantage would be, if I try
> to do a TA QSO I could just stay in the region of 137.7 and those who
> are qrv in qrss3 and only watch the qrss3-sector would get a nice
> signal and thus more fascination for the LF-hobby
Yes, in theory, and very occasionally over the last few years VE/US
beacons have been recorded at QRSS3. In the UK, a few stations can
manage to transmit 1W ERP. Despite that, there is no evidence of a
QRSS3 two-way across the Atlantic.
I suggest you monitor the US beacon transmissions around 137.777kHz
each night. These are very well engineered high power stations and
you will be surprised how difficult the path is, even at their speeds
of about QRSS60..
Better still, try running some overnight transmissions of your own -
there are US stations who will monitor for you if you announce it to
this group.
Good luck.
Mike, G3XDV
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