Alan
Note that reception here is never better than at Dave's with his ocean front location. During
optimum conditions (for me) I can get close to his displayed s/n receptions. Many times I just have
no reception at all.
Jay W1VD WD2XNS WE2XGR/2
----- Original Message -----
From: "Alan Melia" <[email protected]>
To: <[email protected]>
Sent: Sunday, September 27, 2015 12:22 PM
Subject: Re: LF: First MF TA since a longer time
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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