Thank you John......those details tend to confirm the comment I made to
Graham. the results from different receivers are dependent on their
location. This is ratherwhy I suggested that one receiving station
monitoring two or more senders. It would seem that if the ground conditions
are that important then variation amongst different stations, then the
signals might have a portion of the wave arriving via ground
scatter......effectively a form of grounnd following wave. Otherwise I
cannot see that the ground coductivity would have such different effects. I
am assuming that the mail mode "ground bounce" about 2000km down range from
the receiver is over water in all cases??
There is an argument that Graham made that suggests that even with one
receiving station there would be similar effects at the transmitting
end.....more variables demands more data :-))
Are there instances when John 'XKA and Jay receive better signals than Dave
and John 'TAG ....or are they always worse??
The background to this is my re-analysis of my 9 months of measurements of
CFH in 2003. They plainly show that good nights occur with a Dst of more
than -50nT and never occur if the Dst is less than -60nT. However having a
night with say (the magic :-)) ) -20nT does not guarantee good signals.
Selecting nights with around -20nT I cannot find any correlation with any
other parameter, and the spread is quite large......but this is all on one
fixed path. Sorry about the obsessive return to this but difficult problems
are the hardest to leave. :-))
Thanks for all your comments they are all absorbed.
Best Wishes
Alan
G3NYK
----- Original Message -----
From: "John Andrews" <[email protected]>
To: <[email protected]>
Sent: Sunday, September 27, 2015 3:45 PM
Subject: Re: LF: First MF TA since a longer time
After one quiet night, the MF TA activity increased last night. Dave, AA1A
(WD2XSH/17) had 4 spots on DK7FC from 0124 to 0234Z, and 3 spots on DF6NM
from 0234 to 0314Z. I (W1TAG/1) had 3 spots on DK7FC from 0204 to 0234Z,
and 2 spots on DF6NM from 0254-0314Z. Jay, W1VD (WE2XGR) had no TA spots,
but good results to the west.
For Alan's head-scratching, Dave lives right on the Massachusetts coast,
about 200 km south of me. His path to EU does not have the overland
component that I do in southern (inland) Maine. Jay is 330 km southwest of
me, and has a considerable overland path to EU. We all live in an area
with very poor ground conductivity. The path to John, WG2XKA in Vermont,
who is 200 km west of me, is also more difficult.
Anyway, for the moment the best propagation appears to be in the
0200-0300Z range, so if you have shut down and gone to bed by that point,
you may miss out. All of this could change in a day, however!
John, W1TAG/1
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