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Old September 23rd 08, 05:48 AM posted to rec.radio.shortwave
elaich elaich is offline
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First recorded activity by RadioBanter: Sep 2008
Posts: 63
Default Long distance MW reception

wrote in news:53e735f2-a5d3-48c0-b824-f9588a57acf1
@z72g2000hsb.googlegroups.com:

Well, the
more scientifically minded hams that work 1.8 MHz have a theory that
these phenomenal long distance signals come in as a result of
"ducting". The theory is that the outgoing transmission goes up into
the ionosphere and gets trapped there, and then travels a considerable
distance before coming down to earth in some very far distant space.


I have had an extraordinary experience with ducting.

This was back in the early 1990s. I lived in SW VA then. Driving home one
midday, I saw an unmistakable squall line approching, which signaled the
advance of a cold front. It was winter, so there was no lightning.

For some reason, I raced into the house and fired up the MW DX rig.

Within minutes, my local stations were replaced by exotic skip stations
in the Far South. Georgia, Alabama, Missisippi, even Louisiana. This
lasted all of ten minutes. I logged as many of them as I could.

On another winter day a few years later, I was hearing stations from the
northeast in midday that I could only usually hear at night. All the NYC
stations booming in, WWKB, CHUM, etc. This lasted a bit longer, maybe an
hour.

In both cases, the effect was because of a weather front, and the effect
was less than 1000 miles.