Yes. A horizontal, or semi-horizontal, antenna is sensitive to height above ground. You want to be about 1/2 wavelength up for optimum DX results. The way the radiation interacts with the earth provides additional gain - up to 6 dB - at those heights.
Your "inverted V" configuration provides some vertical polarization that has a lower radiation angle, but it's not much. It will be effective for at least short skip down to about 1/4 wavelength above ground where the main lobe is straight up and will scatter off of the ionosphere. That's what many Hams today call a NVIS (Near Vertical Incidence System) antenna. At lower heights the main lobe continues to point straight up but with less and less strength as more of the RF is absorbed by the earth. What you've run into with the SWR is exactly why tuners are so popular. It's very difficult to get an antenna to show a low SWR, especially on several bands, without one. 73, Ron AC7AC -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jay Krishna Sent: Monday, December 31, 2012 6:34 PM To: [email protected] Subject: [Elecraft] K3/100 into DX-CC antenna (HI-SWR) Hi all, Just spent the day putting up a multi-band DX-CC (fan dipole, 80-10M) in an inverted V configuration. Unfortunately, I could not get the center mast extended beyond 20 feet, with one end up ~9 feet from ground, the other, ~5 feet from ground. I am seeing HI-SWR on all bands. Any suggestions on what might be the issue? I was able to get decent SWR with my old 20M monoband dipole, 30 feet up. I have heard that the DX-CC is sensitive to height above ground, and am concerned that 20 feet might be too low. On the other hand, I was hoping it will at least tune well on 20 M at that height, if not all the bands... Appreciate any ideas/suggestions. I don't have an ATU in my K3/100, and was hoping a multi-band fan-dipole like the DX-CC would work well without need for an ATU. 73, Jay (KD6AMA) ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
