Re: [IRCA] Intriguing DXing locations
Manteca the armpit??? No no. That would be Stockton : ) Thank you. Derek Vincent Vmedia360...everywhere On May 4, 2010, at 4:16 AM, Mike Hawkins wrote: I am far from technical on the subject, but I can agree with the dampening effect. I went up to Don Kaskey's house a few times and we listened on car radio and on my Grundig at the beach in San Francisco. I drove the Great Highway south after leaving and had strong signals on several TP frequencies. When I turned inland, the signals dropped off dramatically. Many were gone by the time I was 3 miles inland, though the stronger ones lasted until I was 10 miles in, and the strongest continued on. One night in 1980/1981, I went out to an artichoke patch (I think...it was dark and rainy) north of Santa Cruz with Doug Nyholm (remember him?) and we strung out 1200-1300 foot of longwire on stakes attached to his Yaesu. We had reasonable audio on 30-35 TPs from Australia/New Zealand/Fiji. I had never heard most of them before or after that night. There have been some good exceptions to the rule though...I used to pull in a AM station from Malaysia with some regularity when I lived in Manteca CA, which is politely referred to as the armpit of California. I also had armchair quality on a Central Chinese station on 1525 kHz way back when. Mike Hawkins On Mon, May 3, 2010 at 10:46 PM, Nick Hall-Patch wrote: At 23:04 5/3/2010, you wrote: Those would indeed be great, and away from all forms of RF noise. I was also wondering how close they were to the ocean; my understanding is that going even a few hundred yards or so inland puts a significant damper on TA/TP signals - can any TA/TP veterans confirm/correct this? Hi Kevin, I suspect that the amount of loss is somewhat dependent on the ground conductivity of the inshore land, the frequency of the signal, and the arrival angle of the signals, but only really have data for the second of those suppositions. The others are based on the supposition that a low arrival angle signal from over the ocean will lose strength more slowly over highly conductive land (salt marsh) compared with poorly conductive land (rock) the further it travels. A high arrival angle signal, on the other hand, presumably will not be as affected by ground conductivity so one might assume it will be nearly as strong inland as at the shore. As for the second supposition, a few years ago, John Bryant and I did some simultaneous signal strength recordings at the shore and points up to around two kilometers inland at Grayland, and found that the loss was highest for higher frequency signals, and varied from 1 to 12 dB depending on how far inland one was (but signals were almost always best right at the beach). It didn't seem to be a linear decay, rather there seemed to be reinforcements and cancellations of signals at different points, so one might luck out and hit a "pretty good" spot further inland, so one shouldn't out of hand reject a site a little ways inland. Randy Seaver wrote a good article years ago about this, entitled "Sea Gain" which is IRCA reprint T062, and some of our results did seem to have some theoretical underpinnings (Randy had found some academic work on the subject). Unfortunately, both John and I were pretty busy at the time, and never really finalized any conclusions on the subje! ct"more study is needed" (I'm sure Mike of the Grayland motel would be OK with several weeks of rental from DX researchers.). best wishes, Nick * Nick Hall-Patch Victoria, BC Canada ___ 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 ___ 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
Re: [IRCA] Intriguing DXing locations
I am far from technical on the subject, but I can agree with the dampening effect. I went up to Don Kaskey's house a few times and we listened on car radio and on my Grundig at the beach in San Francisco. I drove the Great Highway south after leaving and had strong signals on several TP frequencies. When I turned inland, the signals dropped off dramatically. Many were gone by the time I was 3 miles inland, though the stronger ones lasted until I was 10 miles in, and the strongest continued on. One night in 1980/1981, I went out to an artichoke patch (I think...it was dark and rainy) north of Santa Cruz with Doug Nyholm (remember him?) and we strung out 1200-1300 foot of longwire on stakes attached to his Yaesu. We had reasonable audio on 30-35 TPs from Australia/New Zealand/Fiji. I had never heard most of them before or after that night. There have been some good exceptions to the rule though...I used to pull in a AM station from Malaysia with some regularity when I lived in Manteca CA, which is politely referred to as the armpit of California. I also had armchair quality on a Central Chinese station on 1525 kHz way back when. Mike Hawkins On Mon, May 3, 2010 at 10:46 PM, Nick Hall-Patch wrote: > At 23:04 5/3/2010, you wrote: > >Those would indeed be great, and away from all forms of RF noise. > > > >I was also wondering how close they were to the ocean; my understanding is > >that going even a few hundred yards or so inland puts a significant damper > >on TA/TP signals - can any TA/TP veterans confirm/correct this? > Hi Kevin, > > I suspect that the amount of loss is somewhat dependent on the ground > conductivity of the inshore land, the frequency of the signal, and the > arrival angle of the signals, but only really have data for the second of > those suppositions. The others are based on the supposition that a low > arrival angle signal from over the ocean will lose strength more slowly over > highly conductive land (salt marsh) compared with poorly conductive land > (rock) the further it travels. A high arrival angle signal, on the other > hand, presumably will not be as affected by ground conductivity so one might > assume it will be nearly as strong inland as at the shore. > > As for the second supposition, a few years ago, John Bryant and I did some > simultaneous signal strength recordings at the shore and points up to around > two kilometers inland at Grayland, and found that the loss was highest for > higher frequency signals, and varied from 1 to 12 dB depending on how far > inland one was (but signals were almost always best right at the beach). > It didn't seem to be a linear decay, rather there seemed to be > reinforcements and cancellations of signals at different points, so one > might luck out and hit a "pretty good" spot further inland, so one shouldn't > out of hand reject a site a little ways inland. Randy Seaver wrote a good > article years ago about this, entitled "Sea Gain" which is IRCA reprint > T062, and some of our results did seem to have some theoretical > underpinnings (Randy had found some academic work on the subject). > Unfortunately, both John and I were pretty busy at the time, and never > really finalized any conclusions on the subje! > ct"more study is needed" (I'm sure Mike of the Grayland motel would > be OK with several weeks of rental from DX researchers.). > > best wishes, > > Nick > > > > > * > Nick Hall-Patch > Victoria, BC > Canada > > > ___ > 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
Re: [IRCA] [NRC-AM] WSM off?
Sounds like they came back about 6:02am ELT; I was listening to an unID Mexican-sounding station when they faded up to full-strength. Earlier, the frequency was dominated here by R Rebelde, Brett Saylor Central PA On Tue, May 4, 2010 at 4:39 AM, Bill Whitacre wrote: > WSM appears to be off this morning - 0839utc. I'm pointing west and > crossing my fingers. > ___ > The NRC AM mailing list > Questions? ow...@nrcdxas.org > NRC/WTFDA Conv 8/27-29 Rochester NY > http://www.nrcdxas.org for the details > ___ 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] WSM off?
WSM appears to be off this morning - 0839utc. I'm pointing west and crossing my fingers. ___ 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
Re: [IRCA] Intriguing DXing locations
Yes, how true. Inland a mile or so, KCIS-630-Edmonds WA is dominant, drive out along the ocean, KWRO-630-Coquille OR takes over the channel and they are further. This is on a car radio. Here off the SW EWE, KWRO is dominant, but not on the van radio. I am less than a mile from the Pacific. Patrick Patrick Martin Seaside Oregon "Come visit us for the 2010 IRCA convention held Sept 24-26 at the Inn At Seaside." ___ 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
