You didn't mention your primary band (to determine how long it is). I have an 80M EDZ (340' end to end of #14, 2- 5/8 wavelength center fed) in the oak trees. It is too low but it is all I can mange (the trees rarely grow above 50' plus airport, HOA, CCR). I have 230 countries (5 on 160) over the last few years with casual operating, so I guess it's doing ok.
Keep it out of the trees as much as possible, feed it with window/ladder line (much lower loss and helps transform the high impedances down) and expect tuning variances with seasons and weather (has to do with the feed and the plant moisture). Use a good common mode choke (every time, every antenna)! If the trees are indeed parasitic, insulation won't affect that, but is still a good idea in pines because the needles are acidic (it'll react badly with the copper). Squirrels are a bigger problem, being rodents they MUST chew to wear their teeth down. Make it as high as you can get it then have fun. Don't stress about straight lines and leave it sloppy enough that the wire will slide through the branches as they wave in the breeze (they never wave the same direction at the same time). If you tension it, something will break. I only anchor the far ends of the wire, everything else sags and is in motion, including the feed. This is reason #2 for insulated wire, it's slicker so it slides through the branches better. Although you didn't ask, if you really have real estate with tall trees and want to play, run the full wave 160 M loop through EZNEC and you'll see that 165' per side (assuming square) will allow you to have decent matches on ALL ham bands <30 Mhz. Someday I'll have to try that one, hard to do on a quarter acre. If you run a similar design based on say 80 meters, every other band is resonant; the 160 meter is good for all bands. I don't know why. Another option is vertically oriented loops at 90 deg angles (because they have directivity) to each other with a remote antenna switch... With a four port switch you could not only change directions, you could change polarity... Or figure out phasing lines to run them together, the phase choice would 'turn' the directivity... Of course there is an absorbent factor with trees too, creating loss, another reason for max height, less tree cover up high. Antenna can be fun! 73, Rick, WA6NHC iPad = small keypad = typos = sorry ;-) > On Jun 25, 2014, at 12:14 PM, Fred Townsend <fptowns...@earthlink.net> wrote: > > Richard: > I have run a double Zepp hung from the trees as you suggest. If you can do it > I would get the antenna across the tops of the trees. 45' is too low for 80M > unless you are running NVIS in which case you are too high at 45'. Keep in > mind that pine trees are parasitic so keep the wire, even if insulated, away > from the trees. Inverted V works if you can't maintain 60'. > 73, > Fred, AE6QL > > > -----Original Message----- >> From: Rstafford12 <rstaffor...@gmail.com> >> Sent: Jun 25, 2014 11:12 AM >> To: elecraft@mailman.qth.net >> Subject: [Elecraft] extended double Zepp >> >> I realize this is another somewhat not on topic post, but it is in regards >> to my KX1 and KX3. I have a mature pine forest; 60 -70 foot trees. How >> compromised would an EDZ be hung 45 feet up about four rows of trees in from >> the perimeter? No branches or needles inside the forest until 50 feet up. >> Richard KD0NPM > > ______________________________________________________________ > 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 > Message delivered to happymooseph...@gmail.com ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
