TopBand: high angle at dawn

[Bob Eldridge]

Tom:

Posting this only, so you don't get it twice.

It will be VERY interesting to see what the 330 ft tower does.

>I suspect wave angle and probably not polarity, but it is only a guess. >I
suspect the wave angle is around 20 degrees or higher at sunrise (and
>mostly on exceptional codx days) , and MUCH lower earlier when the sun >is
not illuminating the upper ionosphere.

My horizon to VK is more than 20 degrees above horizontal.
So I KNOW there are SOME (sometimes S9) VK/ZL signals coming in from above
20 degrees almost every day through our summer, and the GPS signal is there
every day without fail. The signals come in best via the antenna said to
have an optimum vertical lobe about 30 degrees and be mainly vertically
polarized (but until I put up the half-diamond, the horizontal loop was the
bread-and-butter antenna for both transmit and receive). Of course I don't
know what I would hear via lower angles if the mountain were not there, but
I often copy signals that are inaudible to stations near the sea, especially
after sunrise.
As sunrise approaches, the horizontal loop begins to hear the VKs better
than the vertical half-diamond.  If the signal goes into a deep fade, it is
almost always strong when I switch temporarily to the half-diamond. I don't
know whether that is polarization or change of arrival angle.

Receptive as I am to calculations or measurements that confirm my intuition,
Earle's figures comfort me no end. If the bottom of the lobe of my
cloudburners can approximate the top of the lobe of the beautiful monopoles,
I can sleep peacefully.

VE7BS


--
FAQ on WWW:               http://www.contesting.com/topband.html
Submissions:              topband@contesting.com
Administrative requests:  topband-REQUEST@contesting.com
Problems:                 owner-topband@contesting.com