Mel, I personally would not consider elevated radials that are non-resonant - but then all of my antennas are resonant.
I could consider something "balanced", like a 43 foot vertical having 43 foot elevated radials and being fed with parallel feedline to the location of the tuner. I would equate that to a dipole having 43 foot elements on each side of the feedline, but oriented in a different fashion to take advantage of things like the low angle radiation of a vertical antenna. I am not on the edge of salt water, so the great low angle "advantage" of a vertical is not available to me. I recently bought a (used) GAP Titan DX antenna, and installed it - it pales in comparison to my modest height resonant dipoles, and I have made comparisons with DX stations as well as distant domestic stations - the horizontal dipoles always are better. I was expecting better results for the vertical on DX, but failed to find it. (anyone want to buy a GAP Titan DX for about half the price of a new one?). 73, Don W3FPR On 12/20/2010 6:56 PM, Mel Farrer wrote: > It is a matter of loss or lack of it. If you look at the takeoff patterns of > a > vertical antenna on a perfect ground and then with increasing loss, the > pattern > is modified to have increasing less energy on the horizon. However, this is > the > loss factor, not necessarily due to lack of resonance. As one removes the > antenna network from direct ground, and substitutes radials, several things > happen. IF, and that is a big IF, the amount of coupling to ground is > maintained with non resonant radials or resonant radials are used, eff and > match > will remain . Example, a mag mount antenna or a ground plane vertical with > three or four resonant radials works fine and any elevation. Just a point of > thought. > > Mel, K6KBE > > > > > > > ________________________________ > From: Steve Ellington<[email protected]> > To: Guy Olinger K2AV<[email protected]>; Vic K2VCO<[email protected]> > Cc: [email protected] > Sent: Mon, December 20, 2010 3:44:28 PM > Subject: Re: [Elecraft] Inverted-L (was OT: Vertical antenna) > > Guy: > Very interesting.... > > Some of your comments were verified in a recent QST article. > > Mar 2010 - QST (Pg. 30) > > An Experimental Look at Ground Systems for HF Verticals > The author experimented with resonant vs nonresonant radials on the ground > and found performance improved when the radials were cut to electrical > resonance vs just measuring them with a tape. > > Given this, it stands to reason that if the same radial field is used by a > multiband vertical on a higher frequency, the high current point would be at > some distance from the antenna's base thus reducing efficiency. > > Now here's the question.... > Folks assume ground radials to be (non resonant) but that isn't the case. So > what would be the best solution for a multiband antenna with ground radials? > Well if we follow this idea, we would need multiple 1/4 wavelength radials > for each HF band for best performance. > > My inverted L is 50' up and 150' out. I use a separate elevated counterpoise > for each band. I've found that a ground rod and some buried radials have > virtually no effect. I just use them for lightning protection. > > Steve > N4LQ > > ______________________________________________________________ > 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 > > > > > ______________________________________________________________ > 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 > ______________________________________________________________ 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
