"When the antenna is connected directly to the KX3, there is no transmission line, so there is no need to match the antenna to the transmission line. It is putting the ATU at the feed point of the antenna."
Ah. I see now. Light dawns on the Rockies. :) Thanks for the clarification! On Sun, Aug 13, 2017 at 12:09 Walter Underwood <wun...@wunderwood.org> wrote: > In July, five SOTA operators put up seven different antennas on a summit > and compared their performance with WSPR. Six of the antennas were mostly > within 3 dB of each other. The EARCHI antenna (end-fed with transformer) > was between 6 and 15 dB worse than the others. So in one experiment, the > 9:1 transformer did not help. > > > http://reflector.sota.org.uk/t/seven-sota-antennas-compared-using-wspr-on-a-summit/15635 > < > http://reflector.sota.org.uk/t/seven-sota-antennas-compared-using-wspr-on-a-summit/15635 > > > > When the antenna is connected directly to the KX3, there is no > transmission line, so there is no need to match the antenna to the > transmission line. It is putting the ATU at the feed point of the antenna. > > The 26-29 foot length is chosen to avoid very high or very low impedances > in the ham bands down to 40 m Especially, it is not a 1/2 wave on any band. > That makes it easier to match. If you want to work 80 m, use a 53 foot wire. > > The 16 foot wire on the ground is a radial “system”. One radial is a lot > better than none, but you could use more. The length isn’t especially > important because it is capacitively coupled to the ground. Ground > resistance swamps any resonance. > > I first heard about this antenna on this list. It was recommended by > Wayne, N6KR. It is documented on page 9 of the instructions for the KXAT1 > antenna tuner, “...for backpacking use on 40/30/20 meters, a wire length of > 24-28 feet will generally provide good results. […] Ground system: Use a at > least one ground radial, cut to at least 1/8th wavelength on the lowest > band used (16' on 40 meters). When possible, use two or more radials, with > one cut to 1/4 wavelength on each band." > > http://www.elecraft.com/manual/E740054%20KXAT1%20man%20rev%20B.pdf < > http://www.elecraft.com/manual/E740054%20KXAT1%20man%20rev%20B.pdf> > > There is similar advice on page 10 of the KX2 manual. > > http://www.elecraft.com/manual/E740282%20KX2%20owner%27s%20man.pdf < > http://www.elecraft.com/manual/E740282%20KX2%20owner's%20man.pdf> > > Finally, stop trying to think about “balanced” and “unbalanced” because > those words are used in bizarre, inconsistent ways. Voltage, whether DC or > RF, is always between two terminals. With a center-fed dipole, the two > terminals are the elements. With this setup, the two terminals are the wire > in the air and the wire on the ground. > > wunder > K6WRU > Walter Underwood > CM87wj > http://observer.wunderwood.org/ (my blog) > > > On Aug 13, 2017, at 5:31 AM, rich hurd WC3T <r...@wc3t.us> wrote: > > > > Hi all, particularly Walter (since he mentioned it): > > > > I've been bedeviled by a question with multiple possible answers. > > > > I'm a fan of the idea of using a field antenna as Walter describes by > using a BNC - to binding post connector directly to the radio. > > > > I'm leery of that because it flies in the face of what I've been told > about these antennas: I'm assuming the radio BNC connection is unbalanced > and the wires form a balanced antenna, more or less. I've seen deployments > with end-fed 9:1 baluns and without, even documented on YouTube with great > successes. > > > > I can tell you that the 9:1 balun setup doesn't seem to be working for > my current field deployment but I'd sure like to understand why a balun > isn't recommended in this setup. I'd love to just take the wire and put it > on my WonderPole and go for it, but I'd like the understanding first. > Why does this work? :) > > > > Thanks. > > > > On Fri, Aug 11, 2017 at 13:19 Walter Underwood <wun...@wunderwood.org > <mailto:wun...@wunderwood.org>> wrote: > > You can get a quick look at band conditions at http://bandconditions.com > <http://bandconditions.com/> <http://bandconditions.com/ < > http://bandconditions.com/>> > > > > Using Buddistick on 40 m is a real challenge. I would not be surprised > if that was an S-unit or more below a full-size dipole. > > > > Try the simplest field antenna for the KX3, two wires connected directly > to the rig. Get a BNC to double binding post adaptor. Get a wire 26 to 29 > feet long, throw it in a tree and hook one end to the red post. Get a 16 > foot wire, lay it on the ground and connect it to the black post. Let the > ATU tune it and see you can hear. > > > > wunder > > K6WRU > > Walter Underwood > > CM87wj > > http://observer.wunderwood.org/ <http://observer.wunderwood.org/> (my > blog) > > > > > On Aug 11, 2017, at 9:54 AM, Tommy <tomm...@hvc.rr.com <mailto: > tomm...@hvc.rr.com>> wrote: > > > > > > The band has been really crappy lately. Keep tuning around and > listening. > > > > > > 73! > > > > > > Tom - KB2SMS > > > > > > > > > > > > On 08/11/2017 12:33 PM, Mike Parkes wrote: > > >> Okay I am reaching our to the Elecraft enthusiasts here for some > feedback > > >> if anyone cares to chime in. > > >> I am just getting back on the air after years away from the hobby, so > I am > > >> not that familiar with band conditions in general. It looks like the > > >> sunspot cycle is heading for the cellar (if it isn't already there). > > >> > > >> Recently bought a KX3 and a Buddistick vertical (like, 2 weeks ago). > Love > > >> the KX3 it is a great radio... however... so far my efforts to hear > much of > > >> anything, much less make a contact with someone, has been frustrating > to > > >> say the least. I live in an apartment and am surrounded by power > lines for > > >> one thing. The background noise level on 40 is pretty bad varies but > is > > >> s7-9 mostly. I took my setup to a nearby park and the bands were > > >> definitely quieter. So the local manmade noise level is an issue (and > one > > >> reason I chose the KX3 was the hope that its rcvr and filtering could > help > > >> with that.) > > >> > > >> Have yet to make a single contact, so I am just wondering if I just > > >> happened to choose a really lousy period of solar conditions for HF? > Or is > > >> the base loaded vertical a joke? > > >> > > >> I would love to be able to find another ham even close by just to try > and > > >> get some sort of an HF QSO even if it is with someone down the block. > > >> ...I can tune down to the AM broadcast band and was able to hear some > local > > >> AM stations. :) > > >> > > >> Mike AB7RU > > >> > > >> (On a side note the tuner in the KX3 is great!. That thing was able > to get > > >> a match for 80 meters on the Buddistick which was showing something > like > > >> 25:1 swr. The KX3 tuner clicked and rattled for a while and found a > match > > >> to <2:1. Not sure how much actual RF is going out, probably not > much... but > > >> I was amazed it could tune to that high an SWR.) > > >> ______________________________________________________________ > > >> Elecraft mailing list > > >> Home: http://mailman.qth.net/mailman/listinfo/elecraft < > http://mailman.qth.net/mailman/listinfo/elecraft> > > >> Help: http://mailman.qth.net/mmfaq.htm < > http://mailman.qth.net/mmfaq.htm> > > >> Post: mailto:Elecraft@mailman.qth.net <mailto: > Elecraft@mailman.qth.net> > > >> > > >> This list hosted by: http://www.qsl.net <http://www.qsl.net/> > > >> Please help support this email list: http://www.qsl.net/donate.html < > http://www.qsl.net/donate.html> > > >> Message delivered to tomm...@hvc.rr.com <mailto:tomm...@hvc.rr.com> > > >> > > > > > > ______________________________________________________________ > > > Elecraft mailing list > > > Home: http://mailman.qth.net/mailman/listinfo/elecraft < > http://mailman.qth.net/mailman/listinfo/elecraft> > > > Help: http://mailman.qth.net/mmfaq.htm < > http://mailman.qth.net/mmfaq.htm> > > > Post: mailto:Elecraft@mailman.qth.net <mailto:Elecraft@mailman.qth.net > > > > > > > > This list hosted by: http://www.qsl.net <http://www.qsl.net/> > > > Please help support this email list: http://www.qsl.net/donate.html < > http://www.qsl.net/donate.html> > > > Message delivered to wun...@wunderwood.org <mailto: > wun...@wunderwood.org> > > > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft < > http://mailman.qth.net/mailman/listinfo/elecraft> > > Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm > > > > Post: mailto:Elecraft@mailman.qth.net <mailto:Elecraft@mailman.qth.net> > > > > This list hosted by: http://www.qsl.net <http://www.qsl.net/> > > Please help support this email list: http://www.qsl.net/donate.html < > http://www.qsl.net/donate.html> > > Message delivered to r...@wc3t.us <mailto:r...@wc3t.us> > > -- > > 73 (or 72 for the QRP folks), > > Rich Hurd / WC3T > > DMR ID: 3142737 > > Northampton County RACES > > EPA-ARRL Public Information Officer for Scouting > > Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) > Grid: FN20is > > > > ______________________________________________________________ > 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 r...@wc3t.us -- 73 (or 72 for the QRP folks), Rich Hurd / WC3T DMR ID: 3142737 Northampton County RACES EPA-ARRL Public Information Officer for Scouting Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) Grid: *FN20is* ______________________________________________________________ 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
