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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