Topband: Daylight QSO's during the SP

[W2RU - Bud Hippisley]

-----Original Message-----
From: VE6JY
Sent: Monday, December 31, 2007 11:09 PM
To: Topband at Contesting. Com
Subject: Daylight QSO's during the SP

In past years I routinely hear 1530 KFBK Sacromento CA from Edmonton area
during the midwinter and quiet conditions....in early November of 2007, I
heard a number of MW stations
from Europe and the middle east at local noon and thru the afternoon....
*************************

When I responded to VE3MGY's original query about possible daylight
distances on 160, I was assuming that Brian was referring to paths between
stations that were *totally* in daylight.  Clearly, if any part of the path
is in darkness the opportunity for QSOs over that path and distance
increases.

For instance, yesterday afternoon, while it was still very much daylight
here in NY, I was hearing stations from central Europe.  But a look at the
great circle map with superimposed gray line makes it abundantly clear that
only a small fraction of that path was in daylight at the time I was
listening.

As we examine "daylight" paths having greater and greater distances it
becomes harder and harder to find ones that are totally in daylight when we
add the requirement that there be some topband activity on both ends of the
path.  Also, in theory, looking South from VE6 or W2 at mid-day would be an
interesting test, but eventually we get into regions where QRN at one end of
the QSO is apt to be the dominant limitation on the possibility of QSOs.

I suspect Brian's question and my original answer were both colored by our
being Northern hemisphere mid-latitude hams thinking about predominantly E-W
QSOs across the North American continent while it was in daylight.

Bud, W2RU