The experiences of many of us on the East Coast is similar - you don't have to go very far inland at all to lose the TA's that you have at the shore. I can remember back before digitally-tuned radios that you could tune in a TA on the car radio on a good split channel at the shore, and lose it a short way inland.
Russ Edmunds 15 mi NNW of Philadelphia Grid FN20id <wb2...@yahoo.com> FM: Yamaha T-80 & Onkyo T-450RDS w/ APS9B @15'; Grundig G8 AM: Modified Sony ICF 2010's barefoot --- On Tue, 8/7/12, Bill Whitacre <b...@his.com> wrote: > From: Bill Whitacre <b...@his.com> > Subject: Re: [IRCA] [NRC-AM] Recent DXpedition to Grayland, WA & Florence, OR > To: "Mailing list for the International Radio Club of America" > <irca@hard-core-dx.com> > Date: Tuesday, August 7, 2012, 6:11 PM > > On Aug 7, 2012, at 4:14 PM, Nick Hall-Patch wrote: > > > I suspect that the Florence location suffered somewhat > from being 1000 feet > > inland, Gary and Bill. My limited experience has > been that you're generally > > better off being right at the coast for the best DX, > although Gary's experience > > seems to point to an advantage to being right at the > coast and higher up, and > > that phenomenon certainly needs to be looked at more > carefully. > > That's almost what I blurted out in my original email -- > what Gary [and others' research to understand it] may have > stumbled upon is the true nature of 'sea gain' or 'coastal > effect' and that it falls off REALLY rapidly away from the > coast whether you're at sea level or elevated. > > I think it's really hard to 'compare' what Gary's able to > hear on a small portable radio with a super cool FSL antenna > with what I do via a Perseus & DKAZ. Somehow I > give him several 'bonus points' just for doing what he does > LIVE, with cars whoosing by and a few hundred feet above the > pounding surf while I'm literally sleeping! Now that > I've been to where Gary did his last DXpedition I'm VERY > impressed. I would not do what he does. > > I might visit Sea Lion Caves down the road but I would NOT > stand out there with a portable radio and a FSL and cars > whooshing by at sunrise! For that alone he deserves a > '10' on the Olympics scale. > > > There was a research paper done years ago by the BBC, I > believe, showing the > > "coastal effect" as a wavefront moved from the water to > the land, and although > > there were peaks in signal strength as one moved > inland, their location depended > > on the frequency of the received signal, were > compensated for by lower signal > > strength in the area between the peaks, and, overall > signal strength dropped the > > further inland one went. I'll look it > up again when I'm home; I have a vague > > recollection that cliffs might have been incidentally > involved, though I don't > > think that clifftop vs. seashore was investigated. > > I've seen that paper and know some people who had something > to do with it ... assuming they're still alive. It was > incorporated, in some fashion, into the Rio 1979 Final Acts > where the Region 1 & 3 MW stuff was > negotiated/allocated. I remember once writing a TI-59 > 'program' to calculate desired and undesired signals along > radials using the 'Rio Plan.' Had to see if changes we > wanted to make to VOA MW facilities would affect Rss by more > than 0.5 dB -- the limit to having other admins notified! > > Blah, blah, blah ... that's when people still gave a hoot > about AM and HF. :-( > _______________________________________________ > IRCA mailing list > IRCA@hard-core-dx.com > http://montreal.kotalampi.com/mailman/listinfo/irca > > Opinions expressed in messages on this mailing list are > those of the original contributors and do not necessarily > reflect the opinion of the IRCA, its editors, publishing > staff, or officers > > For more information: http://www.ircaonline.org > > To Post a message: irca@hard-core-dx.com > > _______________________________________________ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com