I was amazed to work CN2R, P44W and other DX ops with 75w and dipole at 10'
at 2130z (4:30 pm EST). Frank, thanks for sharing the reason. 40m was quite
enjoyable all weekend.
73s Dave WN4AFP
On Tue, Nov 29, 2016 at 6:13 PM, W8FJ via CQ-Contest <
cq-contest@contesting.com> wrote:
> Nice explanation Frank. You hit the nail right on the head. Thanks!
>
> John, W8FJ...
>
>
>
>
>
>
>
> -----Original Message-----
> From: donovanf <donovanf@starpower.net>
> To: cq-contest <cq-contest@contesting.com>; pvrc <pvrc@mailman.qth.com>
> Cc: ve9aa <ve9aa@nbnet.nb.ca>; Tim Shoppa <tshoppa@wmata.com>
> Sent: Tue, Nov 29, 2016 1:51 pm
> Subject: Re: [CQ-Contest] 40M open early for DX in CQWWCW
>
> Hi Tim,
>
>
> Congratulations, you've discovered some of the affects of low
> sunspot activity on DX contesting strategy. During the CQWW
> CW Contest those affects were compounded by the Earth
> directed affects of an unusually large and energetic solar coronal
> hole.
>
>
> One of the most pronounced phenomena of the night time
> ionosphere during fall and winter is the "mid-latitude trough"
> (Google that term for more detail). Its a region of significantly
> depleted total electron content (much reduced MUF) just
> southward of the northern hemisphere auroral zone. The
> trough occurs during about half of the fall and winter nights,
> and it strongly affects propagation on high latitude paths such
> as the short path from eastern north America to Europe and
> Japan. During about half of those fall and winter nights (those
> nights when the trough is active), the trough typically develops
> near sunset at its westward end and rapidly disappears at
> sunrise at its eastern end.
>
>
> http://www.qsl.net/kl7j/images/latitude%20variations.jpg
>
>
> Last weekend the night time auroral zone was pushed significantly
> southward by the affects of an unusually large and energetic
> earth-directed coronal hole that also pushed the mid-latitude
> trough directly over our north- Atlantic propagation paths to Europe
> and our high latitude short path to Japan. As a result, our best 40
> meter propagation to Europe occurred during north American
> daylight hours and after European sunrise. The mid-latitude
> trough significantly shortens the duration of 40 meter propagation
> to Europe and Japan for stations located at more northerly
> latitudes and somewhat less for stations at more southerly
> latitudes during those nights when the trough is active.
>
>
> Our very brief short path propagation from the mid-Atlantic
> states to Japan occurred near JA sunset (0730-0830Z). Soon
> after JA sunset our propagation to Japan was mostly via the skew
> path that propagates via the tilted ionosphere about 20 degrees
> south of the equator, Our east coast short path to Japan usually
> strongly redevelops near east coast sunrise, but the affects of the
> coronal hole significantly degraded our short path to JA.
>
>
> While the most pronounced affects of the trough are on 40 meter
> propagation, it also significantly shortens the duration of our
> openings to Europe and Japan on the higher bands, essentially
> terminating the openings near sunset at the eastern end of the
> paths during about half of the November through February nights
> when the trough is active.
>
>
> I ts a big mistake to consider 40 meters to be mostly a night time
> DX band near the bottom of the sunspot cycle. Daytime 40
> meter DX is significantly enhanced near the bottom of the
> sunspot cycle by the reduced daytime E-layer MUF which
> otherwise blankets the F layer during most daylight hours nearer
> the top of the sunspot cycle. As a result, DX propagation is
> possible on 40 meters during most daylight hours , especially for
> stations located at higher latitudes from November through early
> February. During those months daytime propagation is common
> from the northern east coast USA to northern Europe even at
> high noon.
>
>
> Close to the bottom of the sunspot cycle, both the short and long
> paths are strongly open from the East coast to Japan on 40 meters
> during many December and early January late afternoons from
> 2130Z to about 2215Z. If you have a directive antenna, some
> JA stations can be worked on only one of those paths if they're
> also using a directive antenna. Without a directive antenna,
> some JA signals can be an unreadable blur of overlapping echos.
>
>
> True long paths from the USA to Japan (not skew paths) rarely
> exhibit scintillation affects that are usually observed on the short
> path because the long path propagates well away from the
> southern auroral zone during the southern latitude summer.
>
>
> 73
> Frank
> W3LPL
>
>
>
> ----- Original Message -----
>
> From: "Tim Shoppa" <tshoppa@wmata.com>
> To: ve9aa@nbnet.nb.ca, cq-contest@contesting.com
> Sent: Tuesday, November 29, 2016 2:12:10 PM
> Subject: [CQ-Contest] 40M open early for DX in CQWWCW
>
> Mike VE9AA -
> You asked several good questions in CQ-Contest.
>
> Below are some of my thoughts on the ebb and flow of band choices in CQWW:
>
> From the EU point of view, they can work most of the other EU's on 40M and
> 80M and 160M for points and mults. Here in NA, VE's only work W's and W's
> only work VE's for points. And even that is lopsided because the VE's have
> a lot more W's to work than W's have VE's to work.
>
> So the EU's are on 40M even before THEIR sunset. And it is that it is
> often advantageous (point wise) for a VE station to stay on 20M much later
> than a W, because the VE can run W's on 20M for points.
>
> The disturbed conditions on 40M after my sundown, caused a lot of us
> W1-W4's to figure out that it was much easier to go to 40M to work EU's way
> before our sundown rather than after. Also, because there was no chance of
> folks like me running JA on 15M like in solar max, we were not spending a
> lot of time running on 15M in the afternoon.
>
> The usual thought that 40M is a "darkness band" is not true, even in
> undisturbed conditions. It's very often for me to CQ on 40M in CWOps at
> 1300Z and get replies from VK's, even though both ends are in sunlight :).
> Occasionally I will be CQ'ing at 1300Z in the deepest of winter, and be
> picked up by skimmers in EU (especially GW8IZR who has the most incredible
> skimmer ears, maybe only met by that VK4 skimmer) even though it is local
> noon in EU.
>
> I had a handful of long-path JA callers on 40M in my afternoon while I
> thought I was CQ'ing for EU. The long path JA's sounded especially clear
> and unwobbly to me. Both ends were in sunlight. Usually I don't get long
> path JA callers until we are closer to winter solstice.
>
> I had a VERY HARD TIME running EU on either 40M or 80M, but no problem at
> all on 20M. This poor conditions on 40M/80M were very unusual for me. I'm
> guessing that 80% of my 20M QSO's were running, and that 80% of my 40M
> QSO's were S&P., and that's just unusual for me.
>
> Mike, you also asked why the EU's weren't chasing us on the skimmer spots.
> A very knowledgeable local shared with me, that in poor conditions the
> pipsqueak EU's who might chase skimmer spots rather than CQ, they don't
> stay up late working 40M, they're in bed, so there are many fewer to reply
> to my CQ's even if we could hear other.
>
> Tim N3QE
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--
Dave Edmonds
PK Ministry Webs
864.288.6678
dave@pkministrywebs.com
www.pkministrywebs.com
"Webs from the Heart"
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