Additional info ......Feed Z *does* change from 1 wire = 72 ohms to 2 wire = 54 ohms at the 60 foot height.
But, as reported, minimal change in feed Z between the 2 wire open and shorted versions. 53.9 vs 54.3, respectively. RH On Sun, Jan 19, 2020 at 6:52 AM Rick Hiller <[email protected]> wrote: > Modeled 80 meter 1 and 2 wire with .1 foot spacing #14 copper at 60 > feet. Open ends and shorted ends. > No, it does not. Minimal change in resonant freq, feed Z and gain. > RH > > On Sun, Jan 19, 2020 at 3:05 AM Nizar Mullani <[email protected]> wrote: > >> Rick, >> >> Chris bright up an interesting point regarding what may be different in >> the antenna if the ends of the wires are connected or not. He says (my >> understanding) that a Cage antenna has the distal ends connected together. >> If not, it is not a Cage antenna. >> >> My question is, if I had a two wires dipole, exactly same length and >> close together, does the antenna behave differently if the ends are >> connected or not? >> >> Nizar K0NM. >> >> On Jan 18, 2020, at 8:10 PM, orin snook via BVARC <[email protected]> >> wrote: >> >> >> Well Done Rick! Much appreciated! >> >> 73, >> KB5F/mm >> ------------------------------ >> *From:* BVARC <[email protected]> on behalf of Rick Hiller via >> BVARC <[email protected]> >> *Sent:* Saturday, January 18, 2020 8:05 PM >> *To:* BRAZOS VALLEY AMATEUR RADIO CLUB <[email protected]> >> *Cc:* Rick Hiller <[email protected]> >> *Subject:* [BVARC] Conclusions of the antenna technical question. >> >> The antenna is a "horse fence" antenna. Google it. 15+ strands of >> #30 stainless wire, separated from each other and woven into a 1.5" wide >> strip of plastic webbing....like a folding beach chair web. >> >> So I was looking for the magic that was claimed. After all y'alls >> comments, one on one discussions and revisiting the web sites marketing >> material and youtube videos, I certainly did not find it.. >> >> In the end, the multiple wires provide only a wider useable bandwidth on >> 80 meters. Other bands too but 80 is the bandwidth eater. No other normal >> antenna attributes are affected. The you tube video shows the antenna as >> a mutiple band 80, 40, 20, 10 antenna and after listening to the video a >> few times it is only by the use of an in shack ATU (tuner) that you get >> "flat" SWR on 40 and 20. (That is another sore subject with me, but later). >> >> 80 meters, the fundamental band of resonance, requires no matching >> network, just like a normal, single wire 1/2 wl dipole. The useable 3:1 >> SWR bandwidth on 80 is pretty good at about 200 KHz...maybe a bit more >> depending on how high you put it up. A single wire dipole bandwidth is >> around 50 to 75 KHz 3:1 swr if you're lucky. >> >> So, in NEC modeling this antenna I did a bandwidth comparative model for >> a single wire and found that a single, copper wire antenna had to have a >> wire diameter of about 4 inches to have the similar bandwidth result. Of >> course, there is no wire 4" in diameter available at Home Depot, so a >> multi-wire "Cage" dipole, as a few had mentioned, is the way to go for >> equivalence. >> >> I guess the benefit of the Horse Feather antenna is that it is a single >> 1.5" wide material that is easily deployed. No putzing around with 15 >> individual wires, just one interwoven web deployment on each side of the >> dipole. >> >> If this is something you think you can use......go to >> >> http://kf4bwg.com/ Horse Fence Antenna >> >> or if you wish to build it yourself....material etc. can be had at >> >> >> https://www.statelinetack.com/item/safe-fence-1-1-2in-wide-poly-tape-200-ft/SLT700567/ >> Fencing material. They also have the end, wire connection clamps >> >> I appreciate all that chimed in to set me straight. Kurt Sterba in >> World Radio Magazine years ago used to write a column debunking the claims >> of the fly by night antenna manufacturers. I wish he were still around so >> he could comment on this horse feather antenna. Also, e-ham has a few >> differing reviews posted. >> >> TNX ES 73.....Rick -- W5RH >> >> Rick Hiller >> *e-mail: [email protected] <[email protected]>* >> >> ________________________________________________ >> Brazos Valley Amateur Radio Club >> Get on the air - 146.94 Repeater >> Volunteer now for the Houston Hamfest >> >> BVARC mailing list >> [email protected] >> http://mail.bvarc.org/mailman/listinfo/bvarc_bvarc.org >> >> > > -- > Rick Hiller > *e-mail: [email protected] <[email protected]>* > *Cell: 832-474-3713* > *Physical: 9031 Troulon Drive* > * Houston, TX 77036* > -- Rick Hiller *e-mail: [email protected] <[email protected]>* *Cell: 832-474-3713* *Physical: 9031 Troulon Drive* * Houston, TX 77036*
________________________________________________ Brazos Valley Amateur Radio Club Get on the air - 146.94 Repeater Volunteer now for the Houston Hamfest BVARC mailing list [email protected] http://mail.bvarc.org/mailman/listinfo/bvarc_bvarc.org
