Topband: Take-Off Angle Question

[Larry Molitor]

--- Bill Tippett <btippett at alum.mit.edu> wrote:
>          From Colorado, I found the following to be
> a good rule of thumb (EU ~40 degrees true bearing):
> 
> Geomagnetic field       Optimum azimuth
> 
> Kp 0-2                  40 degrees (little skew)
> Kp 3-5                  70 degrees (moderate skew)
> Kp 6-9                  110 degrees (major skew)
> 
>          The Ap index here shows why I believe
> we've had such good conditions the past 10 days:


I'd like to add a few "local" observations. Ap and Kp
are good indicators for wide area conditions but I've
had poor correlation to my local results on 160.

The USGS has a magnometer site at Newport, WA about
150 miles NE of my QTH.

http://geomag.usgs.gov/wwwplots/newt.gif

Since I've been monitoring it, I've had much better
correlation. If the Ap and Kp and Aurora have been
quiet for at least 48 hours AND the Newport
Magnonmeter has been flatline over the same period I
can have some hope of an opening on 160. If Newport
has any wiggles at all, absorption seems high and even
if I can hear anything, I can't work it.

Regarding skew; The GCB to EU from here is about 30
degrees, actually spread from 10 to 45 degrees. The
magnetic north pole is about 17 degrees. If there is
enough disturbance to cause skew, the absoption goes
up quick. I can only hear the very largest stations
skewed and then it is extremely rare that they can
hear me. On the other side, I hear skew on VK's
frequently and can work them, but not so for JA's!

73,

Larry - W7IUV
Central WA - DN07dg



		
__________________________________ 
Yahoo! FareChase: Search multiple travel sites in one click.
http://farechase.yahoo.com