To support Peter's statement on s/n differences due to different antennas to
the receiver and local noise, I can add the following:
Local background noise can matter, a lot.
A friend of mine recently build his NCDXF HF beacon Monitoring receiver system
at his QRL site.
During the first few weeks of operation we noted a large difference in s/n
receiving peformance between his site (antenna between low buildings in the
open country) vs my location ( tiny back garden in a city). His omni receiving
antenna is slightly different from mine. The other difference is that my city
location is severely hampered by a lot of local background noise.
See at below weblinks what these two variables (RX antenne differences and
local noise) already offer large differences in s/n:
http://monitorstation.ccms-best.nl/
http://pa5mw.com/
73 Mark, PA5MW
Op 06/23/13, Peter Voelpel <dj7ww@t-online.de> schreef:
> Ulli I don´t agree.
> The figures can not be compared as useful they are.
> The main factor for signal to noise is the local noise picked up by the
> different antennas connected to the skimmers and the qrm noise on the
> frequency at the time of recording.
>
> 73
> Peter
>
>
> -----Original Message-----
> From: CQ-Contest [mailto:cq-contest-bounces@contesting.com]
> <cq-contest-bounces@contesting.com]> On Behalf Of
> Ulli Grunow
>
> After the contest you can check the signal to noise ratio the various
> automatically operating CW skimmer receivers report. As everybody is using
> identical software and many even using same hardware (the great QS1R
> receiver by Phil Covington), the figures reported can be compared.
>
>
> _______________________________________________
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> CQ-Contest@contesting.com
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>
>
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