Yes that is a good page. I had considered elevating the vertical, but with the fiberglass mast I would need to get several more sections, and then wasn't that crazy about the elevated wires over the back yard. If I recall, he wanted a pair of resonant wires for each band for the elevated setup.
Dave Wilburn NM4M Erik N Basilier wrote: > David, > > W.r.t. radials you may want to study the findings of Rudy Severns, N6LF > at www.antennasbyn6lf.com. His findings have also been published in QEX > (spread over several recent issues). Some of his findings in simplified > bullet form: "A number of 1/8 wave radials will be better than half that > number of 1/4 wave radials. At least until you have 32 or more radials." > "Four is just not enough." The latter quote applies to radials on the > ground. In contrast he confirms that four elevated radials work great. > You really need to read it all, and you should certainly not assume that > 1/4 wave radials on the ground are a good choice. > > Personally I can testify that elevated radials can be very very much > better than a poor ground level "ground". Years ago I had put up > inverted L's for 80 and 160. I first tried feeding them against my > existing safety ground system which consists of a number of ground rods; > one the feed point, another at the electrical meter, a couple at my > tower (an important tie-in to my station ground still to be completed). > These are tied together with 4" wide buried copper ribbon, branches of > which also extend to some far-away parts of the lot. Although I achieved > a good impedance match, the received signal strength was incredibly > poor. I then added two elevated 1/4 wave radials for each band, > suspended under the eaves of the 1-story house, trees, and short poles > attached to the fence. The impedance match was still very good, and the > antennas worked very well indeed. I believe I would have had the same > results with verticals. I also recall trying just a few 1/4 wave buried > radials for a vertical way back in my youth, with poor results. I am now > a big fan of elevated radials. If you decide to go with ground level > radials, I suggest you perform a sanity check after you install them: > Temporarily string up one or two 1/4 wave radials at a height of 10 ft > or so, sloping one end down to the feed point. Compare the results from > the temporary radial(s) with results from your radials on the ground. If > the elevated radials work best, consider either making them permanent, > or improving your other radial system by adding more radials, and > possibly making them shorter. > > 73, > Erik K7TV > >> In the near term I want to try out (experiment with) a 33' vertical. >> At Frostfest this year I picked up 32' or so of fiberglass mast. I am >> going to tape a wire to this that is 34' long, twist the mast to wrap >> the slack up, much like a widely spaced helical. >> >> When setup at home, it would (eventually) have a good ground field >> (would start out with 16 radials and work my way up to 60'ish). The >> coax run when used at the house would be less than 40'. >> >> When setup for portable operation (connected to mount I have for my >> trailer hitch, to use when parked) it would have 4 radials of a length >> not yet determined and the coax run would be less than 20'. >> > > ....... > > >> Current plans are for ground mounting. I understand that as radials >> go, more is better. The radials would be black insulated wire on, or >> within 1" of the surface of the ground. They would not be cut to 33' >> or less if the space was not available. >> >> I am curious on the experience of the group with a similar vertical, >> tuner at the rig, and short coax run. > > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
