> As for conditions seeming poorer as one approaches midwinter in
> spite
> of low solar and geomagnetic indices, medium wave DXers
> (listeners)
> have noticed this for years, but no-one seems to have come up
> with an
> explanation. At one time, it was suggested that stratwarms
> were
> associated with periods of higher absorption in the winter
> months,
> but K9LA was not able to find any correlation when he looked at it.
>
> best wishes,
>
> Nick
> VE7DXR
I think that hysteresis might be at work. Just like we do not get the coldest,
baddest weather around the winter solstice but a couple months later, this
could be in play with RF and low band propagation. At low sunspots atmosphere
height shrinks, some inertia comes to play and we see some delay from what the
numbers would suggest.
Before the disturbance condx seem to "heat up".
Plus don't forget the refraction - "conduction" - ducting.
http://www.k3bu.us/propagation.htm
ARRL 160 was interesting that first night condx were better, while numbers
seemed to drop for better second night.
"You just gotta be there when IT happens and have enough antennas" :-)
Thanks for the points amd patience in ARRL 160, sure more fun than not working
your own in CQ WW! Yea, what was with all the dupes?
Yuri K3BU.us, was N2EE/8
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