Message-ID: <27CE89B304674CB9AECC70C0C9580F98@gnat>
From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <CAGZ4oo_Z24ZDw+Tx_oGrwfVJ-v2uOmYurvk1yA2Z7=+S6Q91Ug@mail.gmail.com>, <1513456828917.25265@kuleuven.be> <5A364975.21942.707D5D@roelof.ndb.demon.nl>
Date: Sun, 17 Dec 2017 13:09:47 -0000
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Subject: Re: LF: Re: A robust session on 630-meters : K9FD (/KH6) -> LA2XPA and more...
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Hi Roelof, I have in the past discussed these odd polar paths with Laurence. 
One though is a 'location filter' consider a path where the transition 
through the auroral belt happens to coincide with a ground reflection??

Though I think we are due a wipeout for a couple of days. The Dst has just 
gone to zero nT prior to a dip expected from the Kp=5 this morning.  Another 
effect I have seen is what I refer to as 'leakage' I am not sure about this 
but there is data that shows poor signals after a long geomagmetically qiet 
period. Though the E-layer is theoretically ionised by non-solar effects 
(cosmic rays) there is obviously some effect. The interesting point is this 
poor prop  period can be ended by a low-level geomagmetic event (Kp=4) so it 
is possible that nighttime ionisation levels in the E layer benefit from 
mild geomagnetic activity. We may see more of this as we go into this Solar 
Minimum. these things remain fascinating.

Best Wishes
Alan G3NYK


----- Original Message ----- 
From: "Roelof Bakker" <roelof@ndb.demon.nl>
To: <rsgb_lf_group@blacksheep.org>
Sent: Sunday, December 17, 2017 10:39 AM
Subject: Re: LF: Re: A robust session on 630-meters : K9FD (/KH6) -> LA2XPA 
and more...


> Hello Rik,
>
> T/A propagtion from lower latitude NDB's is very poor at the moment,
> whilst reception from Nunavut is excellent.
>
> There was even a short opening around 10:00 UTC from Churchill at
> the other side of the Hudson Bay. This almost happens every year in
> December / January. However, I have never seen the difference
> between reception from lower Canada and up north as large as it is
> now.
>
> My guess is that a different propagation mode is at work.
> If anyone has more information, it will be much appreciated.
>
> Though trans-polar propagation in Winter is common from northern
> Europe at my latitude (52 N) this is much more rare. Yet, lately I
> could receive 3 NDB's from Alaska here.
>
> 73,
> Roelof Bakker, pa0rdt
>