Hello Stefan !

You're right! Those effects have been observed before. Ossi and I have
watched different closely spaced grabbers (like mine and DF6NM) and
found very similar results. One explanation for this effect is that the
reflecting layer in the atmosphere isn't even and smooth but rather a
"wave"-shaped moving structure. We observed signals coming from east
appearing strong on my grabber and after a while they get weak here. At
the same time DF6NM records stronger signals and this process repeats
with a rough period of half an hour.

So that is what Ossi calls "the Wave" and the goodwill of Mr. Heayside
(makes a difference of at least 20db)!!!

73 es gl 

OE3GHB
Gerhard







Am Donnerstag, den 07.10.2010, 22:11 +0200 schrieb Stefan Schäfer:
> I just saw that Mike/G3XDV appears very much stronger on my grabber
> after 19 UTC while he is much stronger before 19 UTC on the DF6NM
> grabber and almost invisible after 19 UTC. The difference of distance
> between Markus and me is about 180 km. QRN is not the reason but the
> signal strengh itselfe.
> 
> 
> 
> 
> I assume this effect is not been observed the first time ;-)
> 
> The two dots apper strong on both locations. So it was a 'dip'?
> 
> 
> 
> 73, Stefan