Hi Csaba,
My experience is that an extensive radial system on the ground performs significantly better than a few elevated radials. I suspect its difficult to obtain nearly equal currents among a small number of elevated radials. There is nothing wrong with gull wing elevated radials, but in my experience they shorten the effective length of the vertical. 73 Frank W3LPL ----- Original Message ----- From: "HA3LN" <[email protected]> To: [email protected] Sent: Wednesday, December 18, 2019 8:57:40 PM Subject: Re: Topband: Temporary antenna suggestion for 160 Hi Frank, So the gull-wing elevated setup should be dropped from the performance point of view, right? I have a 26m spider-pole and just wondering how to setup the radials for that but considering you wrote no sense to make the radials into gull-wing then. Thanks and 73! Csaba HA3LN / HG3N http://ha3ln.hu/ On 2019-12-16 22:04, [email protected] wrote: > Hi Mike, > > > Years ago my 4-square transmitting array used "gull-wing" elevated > radials sloping 45 degrees from the feedpoint at ground level to about > ten feet high. > > > When I replaced the radials with sixty 120-foot radials laid on the ground > I had to shorten the verticals by about five feet to maintain resonance, > suggesting that the current at the bottom five feet -- or so -- of the > verticals > was attenuated by the sloping radials in close proximity to the verticals. > > > As an aside, the performance of the array improved dramatically... > > > 73 > Frank > W3LPL > > > ----- Original Message ----- > > From: "Mike Waters" <[email protected]> > To: "thoyer" <[email protected]> > Cc: "topband" <[email protected]> > Sent: Monday, December 16, 2019 8:52:41 PM > Subject: Re: Topband: Temporary antenna suggestion for 160 > > CORRECTION > > It was just pointed out to me that I neglected to mention that the > feedpoint on my 160m inverted-L was much lower than 10 feet high! > > The tuner sits on the earth, and the two wires go straight up from that to > the insulator block holding the antenna and the radials, which is less than > 4 feet high. > From that point, the two radials angle upwards at roughly 45° (?) to nearby > trees, and level out at 10' high to the North and to the South all the way > to the ends. (The South radial zigzags back and forth since the distance > from the base to the neighbor's fence in that direction is less than 1/4 > wavelength.) > > I had photos of it online, but w0btu.com crashed. Looking for a place to > upload it to. > > I hope this makes sense. Sorry for the lack of details below. > > 73, Mike > W0BTU > > > On Sun, Dec 15, 2019, 8:22 PM Mike Waters <[email protected]> wrote: > >> Do the inverted-L, but use at least two 10' high 1/4 wave radials. >> >> Do NOT use an RF ground rod, or any radials on or near the earth. Just >> connect the coax shield to the junction of the radials and any remote >> tuner. At that point a good choke balun is necessary. >> >> Leaving out the choke or grounding the shield will result in very poor >> performance. >> >> 73, Mike >> W0BTU >> >> >> On Sun, Dec 15, 2019, 7:04 PM thoyer via Topband <[email protected]> >> wrote: >> >>> With only 9 more to go for DXCC on 160 and all of the recent posts about >>> how good the band has been recently "best in years....) I find myself with >>> no >>> antenna for the low bands and cringing after each post on how good the >>> band has been. >>> ... >>> Options - I have a 45' tower with TH6DXX, 6m and 2m yagis. I could easily >>> string a makeshift inverted L with about 45' vertical and around 100' >>> horizontal. This I could string up in a few hours. the Horizontal portion >>> would be pointed south. Not the best of configurations but that's what I >>> have to work with. ... >>> >>> Tom >>> W3TA >>> >>> >>> > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband Reflector > > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband Reflector > _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
