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LF: Re: SM6LKM Jason beacon affected by multipath

To: [email protected]
Subject: LF: Re: SM6LKM Jason beacon affected by multipath
From: "Johan Bodin" <[email protected]>
Date: Fri, 9 Aug 2002 21:47:41 +0200
References: <[email protected]>
Reply-to: [email protected]
Sender: <[email protected]>
Good evening Wolf & All

The 7 MHz signal suffers from multipath, every Jason symbol (tone) now consists of two peaks separated 50..150 mHz (m=milli, M=Mega, the European way). The decoder doesn't like it, but on a waterfall it looks interesting (like ancient symbols..).

This is interesting. 100 mHz doppler shift at 7 MHz corresponds to a speed of
3e8*0.1/7e6 = 4.3 m/s (neglecting relativistic stuff :-). This is the speed at 
which
the two (assuming two) path lengths differ. At this short distance it is almost
NVIS propagation. Could it be two reflecting layers that move vertically with
respect to each other when the sun sets?

73
Johan SM6LKM




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