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No, i'm not confused about the difference between horizontal and vertical polarization. My "anecdotal stories" are just that, and i make no apologies for them. I cannot offer scientific data to prove anything, since its the embodiment of much operating experience. I am well versed in the methodology of "scientific data " collection. My stories weren't even directed to you anyway, since you are of the mindset that all knowable propagation and antenna radiation phenomonon are already embodied in NEC-4.Since i outlined a number of antennas that were both vertically and horizontally polarized, and some containing both polarizations, it ought to be clear that i am of the opinion that propagation is better at the seashore, and on the water, using either. 1) the horizon is clear and unfettered. There is nothing to attenuate the radiated signal, except the inverse square law of propagation. 2) the excellent conductivity of salt water leads to development of the lowest possible angle of radiation for both polarizations. 3) it is entirely possible that an antenna at some height above ground, over sand, appears to be even higher than the height above ground level., dependent on the salt content, moisture index, water table, soil composition, etc, to be found in the ground under the antenna. 4) there may be even more influences at work than i realize. I've lived at the seashore; on an island; in the mountains of Northern Arizona; in the great S.W. desert; in the coastal plains and Piedmont regions of N.C., etc. I've had some good antennas and some "dogs." I've had an opportunity to see propagation in a number of settings. I remain unconvinced that NEC-4 is the "be all" and "end all" as regards this subject. Much more remains to be learned. Until human beings know it all, NEC whatever, will not be able to accurately reflect all "real world" conditions. 73 Roy Lincoln WA4DOU ------------------------------------------------------------------------- ------------------------------------------------------------------------- ----------------------------------------------------------------------- On Tue, 9 May 2000 15:27:46 -0700 "K2KW" <K2KW@prodigy.net> writes: > I think that Roy, WA4DOU is a little confused what antennas he was > quoting > in his reply. Most of the situations he references were actually or > likely > using verticals... > > First off, anecdotal stories are just that, anecdotal. You need to > be a > little more > convincing to dispute what models like NEC-4 are saying. Also, you > also > need to objectively examine some of the statements you just made... > > >Antennas were low dipoles(20-30 ft. high) and a windom > > 20 ft. high at one end and 35 ft. high at the other. My output > power was > > about 15-30 watts on 10-20 meters. I worked piles of dx, on cw, > > So what's your point? I was recently at N6BT's house using a 100w > GE light > bulb on 10m, and we were able to work DX too. By just going by > anecdotal > information, I could make the following claims: > > * miniature antennas are excellent performers > * The antenna only needs to be 3' high > * 100w will work all the DX I can hear (which isn't much on a light > bulb) > > Obviously, I would be highly misinformed and misled by my > observations based > on the limited experience of using the light bulb, regardless of how > well I > thought it "worked". What is missing is a reliable reference with > which to > compare my observations. > > >i found > > the propagation to be excellent, anywhere i went. My power output > was 100 > > watts and my antennas were either verticals or sloping dipoles. > > Huh? Thank you for supporting that vertically polarized antennas > over salt > water are good antennas. (BTW, sloping dipoles have a large > vertical > polarization component). > > > In 1932 Bell Labs conducted test to determine where to locate > shore > > stations for communicating with ships at sea. These tests were > conducted > > in the 66 and 33 meter bands, under both day and night > conditions.They > > reported" attenuation of 8 db to 12 db is observed at a distance > of one > > mile inland for both 33 and 66 meter transmissions." > > What types of antennas were used? There is not enough info given > here to > draw any reliable conclusions. If they were verticals, then it > makes > sense (see below comment). > > > reminded me that when i was a kid and broadcast band dx'ing, i > logged > > WAPE in Jacksonville ,Fl. while living in Morehead City, N.C. In > the 60's > > and 70's, whenever i went home to visit my parents, i'd frequently > look > > for WAPE on the car radio(680 khz. if i remember correctly).At and > around > > my parents house(300 yds. from a salt water sound, i could receive > it. > > But a mile further inland, it became unreadable. > > Again, evaluate what you just said. Your statement seems out of > place if > you are trying to use it to support the horizontal enhancement > theory you > THINK is correct. AM broadcast stations are vertically polarized. > And most > car antennas use vertical whips (vertical polarization). The ground > within > 300 yards (surely a rough approximation) could have a water table > that was > near the surface and at least brackish, making a much improved > ground for > vertically polarized signals than a mile inland. (The ground > condition > applies to receive antennas, as well as transmitting.) I have no > doubt > that WAPE's signal was enhanced by the ocean. > > Take a portable short wave radio with a vertical whip and go to the > ocean. > Tune in a good ham signal, and start walking away from the water. > The > signal will drop off > dramatically in a very short distance. Also, try turning the > antenna > horizontal and repeat the test of walking away from the ocean and > see what > happens... > > FYI - I have installed well over 100 vertical antennas on the ocean > in my > various contest DXpeditions, and have also run numerous tests (in > controllable conditions) to examine the performance of verticals vs. > Yagi's > over salt water. In all cases, the verticals had the predicted gain > over > the horizontal array, which to me is a good argument that the > antenna models > have it right (besides, before I even said one word to this > reflector, I > called a bunch of respected ham antenna and propagation gurus - I'm > friends > with them all - and confirmed that horizontal polarization does not > get any > enhancement from salt water). > > Unfortunately in ham radio, the following quote is all too common > "These are > the conclusions upon which we based our facts." (by Adlai > Stevenson). > > Before anyone else uses anecdotal info, I suggest you go to the ARRL > handbook, antenna manual, etc to read up on antennas and > propagation. > Horizontal antennas do not gain any efficiency over salt water. > > Kenny K2KW > > PS for a little more info on verticals, visit my web site at: > http://pages.prodigy.net/k2kw and look at the 6Y2A page. > > > > > > > > -------------------------------------------- > Force12Talk mailing list provided as a service by Force 12 Antennas, > Inc. > Force 12 Web site: http://www.qth.com/force12 > > Submissions: send to Force12Talk@qth.com > To unsubscribe: send a blank e-mail to Force12Talk-leave@qth.com > Force12Talk Message Archive: http://www.qth.com/force12/list/force12talk > For problems with the list, contact force12@qth.com > > ________________________________________________________________ YOU'RE PAYING TOO MUCH FOR THE INTERNET! Juno now offers FREE Internet Access! Try it today - there's no risk! 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