Jim, it doesnt surprise me since youre generally North of the auroral zone
so the signals have to go under it otherwise they are reflected or absorbed.
The effect seems to be more pronounced on 80 and higher until you get to 10M
and up thru 2M where QSO's are made by bouncing signals off the ionization.
Its also at high angles so the distances involved are about 1200 miles
maximum on 2M which for me is roughly this side of the Mississippi River.
OTOH Ive also used aurora to link to E or F to work JA and KL7 on 6M.
Carl
KM1H
----- Original Message -----
From: "Jan Erik Holm" <sm2ekm@bdtv.se>
To: "Bob Eldridge" <r.c.eldridge@ieee.org>; <topband@contesting.com>
Sent: Monday, October 17, 2011 12:49 AM
Subject: Re: Topband: high take-off angle
Yes well I might explain my statement a little. First of all I
have read all the books by ON4UN and also this by NM7M together
with lots of other writeups etc etc. I am NOT saying that thats
not true. What I´m saying is at my northerly latitude I can just
not see any useful high angle and I´m talking about stuff further
away then 150 miles, this holds true for both 80 and 160m. I do
have great experience in 80m DX-ing and also 160m but more experience
on 80m so far. For example I´m quite sure I´m the one in Europe
that has made the most "long path" QSO´s into the USA on 80m and
this goes back into the late 1960´ties. I have tried a zillion
RX antennas on 80 and 160 and the clear conclusion is that I
have to get the wave angle below 25 degrees or even much below.
For example, this means that Beverage antennas has to be made
longer than most people think, IMO at my latitude longer then
3-4 wl or even much longer then they really start to performe.
In my book 25 degrees or lower is low angle by the way.
The further down towards the equator one gets it seems like there
is more and more high angle that can be used but not this far
north as 67 degrees latitude.
I think it has to do with the D-layer. At this latitude with
geomagnetic activity most every day the D-layer will be a player
in the equation most of the time and you simply do not see that
further down towards the equator. So the high angle stuff that
"might" have been useful will get absorbed in the D-layer and
what you need to do is sneak in and out below the D-layer.
I better stop before it gets booring!
73 Jim SM2EKM
------------------------
On 2011-10-17 05:20, Bob Eldridge wrote:
> Hi Jim
> Twenty years or so ago NM7M wrote a program in DOS that predicted the
> position of the "tilt" in the E layer on the dark side of the
> terminator, more than usual refraction at that point causing a
> steeply downward signal as it exits the layer. Believing this, I made
> sure I had some antennas that responded to high angle, and they often
> provided better results than the high vertical loops just at that
> time, resulting in hundreds of early morning QSOs with VK and ZL.
> The band "opened earlier" for the lower angle response antennas, but
> they ceased to be better about half an hour before sunrise. It was
> common experience for West Coast stations to see better signals from
> the Pacific on Inverted Vees than on monopoles just before sunrise.
> I suppose if one has only one antenna, a low angle response one is
> better for DX, as long as it has some response at 20 or 30 degrees,
> but some QSOs will be missed.
> Bob VE7BS
>
> ----- Original Message ----- From: "Jan Erik Holm" <sm2ekm@bdtv.se>
> To: <topband@contesting.com>
> Sent: Sunday, October 16, 2011 8:15 AM
> Subject: Re: Topband: high take-off angle
>
>
>> This I have NEVER seen in SM2 land, the lower angle the
>> better. Jim SM2EKM
>> --------------------------
>
>
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