[IRCA] more on DXing a little bit inland

[Nick Hall-Patch <nhp@xxxxxxxx>]

Further to shooting down my speculation about 1000 feet inland having any
significant effect on Bill Whitacre's DX, here's a comment based on my own
experience by John Bryant, from over six years ago:

"At the Annual Big Bash at Grayland this season (October 2005) Nick and I
gave up most of one night to try to quantify the decrease in MW TP signal
strength as one moves inland from the beach. Since we were dealing with
signals from the Far East, they were arriving at the beach a bit obliquely,
from the WNW to NW. We found one location where one of us could move
directly inland (due East), by stages, for about 2 km. while the other team
member member moved North up the beach, by stages, so that we would remain
~aligned with the incoming wave. We were connected by walkie-talkie radios
. Our data gathering equipment consisted of twin battery-powered set-ups of
a McKay-Dymek DR-333 computer controlled receiver and laptops for operating
the radios in an automated pattern and to auto-log the results on ten
different TP signals. (one each were LW and SW). For the first 1.5 km., the
topography was dead flat at about 10 feet above high tide. At the 1.5 km.
mark, the land rose about 50 to 75 feet in an abrupt and flat-topped
earthen bluff.

The results were not what we expected.... a rather rapid diminution in
signal strength. Instead, the AVERAGE of the 8 MW signals stayed very close
to the same, even 2 km. back from the beach. Looked at individually,
though, the signals varied in strength by up to 5 dB from one test location
to another. For instance 594 was down 5 dB only .5 km inland, but
rebounded to +2 dB at 2 km inland from the beach. We were at each test
location for a ten minute logging session, BTW.
Signal strength on 972 maintained about equal strength, except at 2km.
inland, where it was actual up a couple of dB.

......

I, for one, was shocked that the levels over a km. or two inland could be
at or even quite near the ones on the beach itself. I'm still gonna try to
get as close to the beach as possible, but if I'm a km. inland because of
campground location, etc., I'll not throw up my hands and catch up on
sleep.... for sure!"

Unfortunately, we never followed up on that experiment; even writing it up in a
cogent manner seemed difficult at the time, and it never happened.   I recall my
day job being particularly crazy then, and John also must also have had other
fish to fry.  Since then of course, a lot of nasty water has flowed under the
bridge, and John won't be helping out anymore except in spirit.

The bright side is that present day SDRs would make repeats of the experiment
somewhat more detailed and accurate, though one would likely need to set up or
modify some analysis software.  Using the same antenna at each site shouldn't be
impossible; we used small AMRAD active antennas mounted at the same height above
ground for each setup, and tested each setup side by side at the beginning of
the experiment to verify similar response to DX. 

best wishes,

Nick


-- 
Nick Hall-Patch
Victoria, BC
Canada

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