Antenna?
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What antenna do you use for portable operation? I have 66 foot doublet
fed with 300 ohm line and a 85 foot wire with a 17 foot counterpoise. Any other suggestions and ideas. All will be appreciated. Jimmy, AE4DT _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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I actually use a Buddipole. See www.buddipole.com for more info.
It's a great antenna !!! Very portable and covering from 2M to 40M !!! See www.eham.net for more comments about this great portable antenna !!! 73 Le 04-07-02, à 20:30, Jimmy Lee a écrit : > What antenna do you use for portable operation? I have 66 foot doublet > fed with 300 ohm line and a 85 foot wire with a 17 foot counterpoise. > Any other suggestions and ideas. All will be appreciated. > Jimmy, AE4DT > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft Help: > http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com Jean-François Ménard / VA2VYZ [hidden email] Club d'Astronomie Amateur de Sherbrooke Club Radio Amateur de l'Estrie Mon site web personnel : http://homepage.mac.com/jfmenard =============================================== _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Jimmy Lee-4
On Fri, Jul 02, 2004 at 08:30:15PM -0400, Jimmy Lee wrote:
> What antenna do you use for portable operation? I have 66 foot doublet > fed with 300 ohm line and a 85 foot wire with a 17 foot counterpoise. > Any other suggestions and ideas. All will be appreciated. > Jimmy, AE4DT I use a MP-1 vertical (the Elecraft gray version from the Elecraft web site, which has additional mojo). Bob, N7XY _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Bob,
Done any comparisons of the MP1 with a full size vertical or St Louis vertical on 40 meters ? Thanks, Brian n6iz Bob Nielsen wrote: >On Fri, Jul 02, 2004 at 08:30:15PM -0400, Jimmy Lee wrote: > > >>What antenna do you use for portable operation? I have 66 foot doublet >>fed with 300 ohm line and a 85 foot wire with a 17 foot counterpoise. >>Any other suggestions and ideas. All will be appreciated. >>Jimmy, AE4DT >> >> > >I use a MP-1 vertical (the Elecraft gray version from the Elecraft web >site, which has additional mojo). > >Bob, N7XY > >_______________________________________________ >Elecraft mailing list >Post to: [hidden email] >You must be a subscriber to post to the list. >Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm >Elecraft web page: http://www.elecraft.com > > > > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Bob,
My favorite antenna for portable operation has been the PAC-12, by Pacific Antenna. I built the home brew version some months before they began marketing a commercial one. I've used it on 40, 30 and 20 meters, and have recently wound coils for 17 and 15 meters. I haven't had the opportunity to test the 17 and 15 meter coils, but I'm sure they will work as well as the other ones do. I have a cheap ($4.99 when on sale) Harbor Freight canvas tool bag that's about 15" long that easily houses all the parts and a decent chunk of feed line to carry it in. Before getting my K2, I used it mostly on 20 meters with a Small Wonder Labs DSW-II-20, with excellent results. 46 states and even a few DX countries, including Japan. It's performance is better, distance wise than any of the wire antennas I've managed to put up in field locations. Now, mind you, my luck with wire antennas has been atrocious up until field day this year. I like the PAC-12 though for the fact that you do not need a tuner with it. Once adjusted, and I use one of the 4 States QRP group's "Tenna Dipper" antenna analyzers designed by Steve Weber, KD1JV to adjust it, It radiates quite well, and the radio likes it. If you home brew it, parts shouldn't cost more than 20 bucks for the masting, one coil and the whip. Additional coils can be as cheap as a couple of bucks, and the PVC parts are readily available at most hardware/home improvement stores. The counterpoise for this antenna consists of 3 or more (more is better) 10 foot long radials laid out on the ground. I use 7 with excellent results, and have gotten real good results with only 3. I've even been experimenting with a pair of them in an easily packable phased array, but due to limitations, 20 meters is the only band I've tried for this with promising results. Not much forward gain, but a good null off the back and maybe (I don't have equipment to measure it) 1db forward. It does improve the forward signal somewhat, but without a real test range and good measuring equipment, I have no real idea if it really works or if I'm just perceiving a slight gain. Anyway, the other antenna I have used is an inverted L approximately 130 feet long and placed as high as possible in the trees. Takes a while to set up, but on 80, 40, 40 and 17 meters, using an LDG QRP tuner, it produced lots of contacts. Overall, the PAC-12 takes less than 10 minutes to set up or take down, is light to carry, and produces lots of contacts. IMO it's probably the best bang for the buck if you build it yourself. There's a set of plans available on the AMQRP website www.amqrp.org under the "Projects" tab and listed as the KA5DVS PAC-12 antenna. Jim Sheldon, W0EB K2 #4338 > Bob Nielsen wrote: > > >On Fri, Jul 02, 2004 at 08:30:15PM -0400, Jimmy Lee wrote: > > > > > >>What antenna do you use for portable operation? I have 66 foot doublet > >>fed with 300 ohm line and a 85 foot wire with a 17 foot counterpoise. > >>Any other suggestions and ideas. All will be appreciated. > >>Jimmy, AE4DT > >> > >> > > > >I use a MP-1 vertical (the Elecraft gray version from the Elecraft web > >site, which has additional mojo). > > > >Bob, N7XY > > > >_______________________________________________ > >Elecraft mailing list > >Post to: [hidden email] > >You must be a subscriber to post to the list. > >Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: >Elecraft web page: http://www.elecraft.com > > > > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Instructions for the Pac-12 antenna can be found here:
http://www.njqrp.org/pac-12/index.html It's hard to find from the home pages of the other QRP sites listed... > Overall, the PAC-12 takes less than 10 minutes to set up or take > down, is light to carry, and produces lots of contacts. IMO it's > probably the best bang for the buck if you build it yourself. > There's a set of plans available on the AMQRP website www.amqrp.org > under the "Projects" tab and listed as the KA5DVS PAC-12 antenna. _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Jimmy Lee-4
Jimmy Lee wrote:
>What antenna do you use for portable operation? Hi Jimmy, I've been interested in portable HF operation, from campsites primarily, for about 30 years. I've tried just about everything for antennas, and wasted a lot of money on commercial vertical and loop abominations. About ten years ago I went back to the best and cheapest performer I'd ever found: A resonant dipole feed with coax. I use very flexible multi-strand 14 ga. wire in a dipole that is about 66 feet long, with NO balun at the center insulator. I've placed six insulators in each leg, with a jumper/aligator clip permanently soldered to the outboard segment at each insulator. Using this arrangement I can set up a resonant dipole for every ham band from 40 through 10 meters by connecting the jumpers across the appropriate insulators. All insulators are made from small PVC pipe. I seldom raise it above eight to ten feet, so band change only takes about a minute. Using this antenna and a TS-50S, I worked more than 40 countries (Japan through Russia through South Africa and points in between) from a campsite a few years ago during a CQWW contest. I can send a .pdf file with a detailed description, should anyone be interested be interested. 73, Mike / KK5F _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Sherman Banks
Sherman, and all,
Any objective measures of performance of these antenna's ? Vertical vs Pac-12 / MP-1 ? Brian n6iz Sherman Banks wrote: >Instructions for the Pac-12 antenna can be found here: > >http://www.njqrp.org/pac-12/index.html > >It's hard to find from the home pages of the other QRP sites listed... > > > >>Overall, the PAC-12 takes less than 10 minutes to set up or take >>down, is light to carry, and produces lots of contacts. IMO it's >>probably the best bang for the buck if you build it yourself. >>There's a set of plans available on the AMQRP website www.amqrp.org >>under the "Projects" tab and listed as the KA5DVS PAC-12 antenna. >> >> > >_______________________________________________ >Elecraft mailing list >Post to: [hidden email] >You must be a subscriber to post to the list. >Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm >Elecraft web page: http://www.elecraft.com > > > > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Brian,
The HF Pack organization sponsors and annual antenna shootout. The 2002 results for vertical antennas can be found here: http://tinyurl.com/2lzgm Scroll down the page and you'll see the MP-1's and the Pac-12 comparisons. 73 Jeff KB9ZUR ----- Original Message ----- From: "brianboschma" <[hidden email]> To: "Sherman Banks" <[hidden email]> Cc: "Elecraft Mailing List" <[hidden email]> Sent: Saturday, July 03, 2004 3:30 PM Subject: Re: [Elecraft] Antenna? > Sherman, and all, > > Any objective measures of performance of these antenna's ? Vertical vs > Pac-12 / MP-1 ? > > Brian n6iz > > > Sherman Banks wrote: > > >Instructions for the Pac-12 antenna can be found here: > > > >http://www.njqrp.org/pac-12/index.html > > > >It's hard to find from the home pages of the other QRP sites listed... > > > > > > > >>Overall, the PAC-12 takes less than 10 minutes to set up or take > >>down, is light to carry, and produces lots of contacts. IMO it's > >>probably the best bang for the buck if you build it yourself. > >>There's a set of plans available on the AMQRP website www.amqrp.org > >>under the "Projects" tab and listed as the KA5DVS PAC-12 antenna. > >> > >> > > > >_______________________________________________ > >Elecraft mailing list > >Post to: [hidden email] > >You must be a subscriber to post to the list. > >Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/subscribers.htm > >Elecraft web page: http://www.elecraft.com > > > > > > > > > > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Jimmy Lee-4
Hi Jeff,
What a neat site! Very interesting comparisons...tnx for the link. Now all I have to do is find that bag of plumbing parts I bought on that snowy February afternoon and I can build my PAC-12! Tom ---------------------------------------------------------------------------- ---------------------- Daddy, why do they call it the "World Series" if its always played in the Bronx? -----Original Message----- From: Jeff Imel <[hidden email]> To: [hidden email] <[hidden email]> Date: Saturday, July 03, 2004 4:57 PM Subject: Re: [Elecraft] Antenna? Brian, The HF Pack organization sponsors and annual antenna shootout. The 2002 results for vertical antennas can be found here: http://tinyurl.com/2lzgm Scroll down the page and you'll see the MP-1's and the Pac-12 comparisons. 73 Jeff KB9ZUR ----- Original Message ----- From: "brianboschma" <[hidden email]> To: "Sherman Banks" <[hidden email]> Cc: "Elecraft Mailing List" <[hidden email]> Sent: Saturday, July 03, 2004 3:30 PM Subject: Re: [Elecraft] Antenna? > Sherman, and all, > > Any objective measures of performance of these antenna's ? Vertical vs > Pac-12 / MP-1 ? > > Brian n6iz > > > Sherman Banks wrote: > > >Instructions for the Pac-12 antenna can be found here: > > > >http://www.njqrp.org/pac-12/index.html > > > >It's hard to find from the home pages of the other QRP sites listed... > > > > > > > >>Overall, the PAC-12 takes less than 10 minutes to set up or take > >>down, is light to carry, and produces lots of contacts. IMO it's > >>probably the best bang for the buck if you build it yourself. > >>There's a set of plans available on the AMQRP website www.amqrp.org > >>under the "Projects" tab and listed as the KA5DVS PAC-12 antenna. > >> > >> > > > >_______________________________________________ > >Elecraft mailing list > >Post to: [hidden email] > >You must be a subscriber to post to the list. > >Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/subscribers.htm > >Elecraft web page: http://www.elecraft.com > > > > > > > > > > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Jimmy Lee-4
Jeff Imel wrote:
> The HF Pack organization sponsors and annual antenna shootout... > http://tinyurl.com/2lzgm That is a pretty interesting site. Thanks for the URL. It confirms the very dismal performance of *all* those "popular" HF short loading-coil verticals in comparison to the most simple, basic, inexpensive quarter-wave vertical. TANSTAAFL! Likewise, the horizontal antenna comparisons confirm the overall superiority of a simple dipole over other horizontal types being tested. A comparison of all tested horizontal and vertical antennas against the half-wave horizontal dipole would have been interesting. I'm sure it would have shown a very significant advantage of a horizontal dipole over any vertical tested. At campsites I've made several side-by-side tests of various verticals versus a resonant dipole and have *always* found found verticals to be very poor performers, when directly compared to a cheap horizontal dipole. Plus, don't forget the counterpoise or ground required by the vertical. If one chooses to use a multi-band dipole for portable operation, I'd suggest staying away from *trap* dipoles. Aside from the traps being heavy and bulky, the traps really narrow the bandwidth of each band compared to that of a single band dipole. That's why, for the seven-band portable dipole that I put together, I use small, lightweight, home-made PVC insulators with manually connected jumpers around them to change the band of resonance. The second-best portable antenna I've ever used was a random-length dipole, center fed with 450 ohm ladder twin lead and a tuner. The main problem presented was the routing of the excess twin lead. Every camp site is different, and it *does* make a difference if you coil up the excess or allow it to lay on the ground. The resonant dipole allowed me to return to the joyful and trouble-free world of RG-8X coax! Also, most small tuners aren't real balanced line tuners, so there are losses in the ferrite balun that nearly all such tuners use to support balanced line feed. I think I'm going to build a light-weight four-band version of my portable dipole for the four bands on my K1. Right now, I just use the seven-band version that I originally built for my old TS-50S. 73, Mike / KK5F _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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On Sun, 2004-07-04 at 06:47, Mike Morrow wrote:
> It confirms the very dismal performance of *all* those "popular" HF > short loading-coil verticals in comparison to the most simple, basic, > inexpensive quarter-wave vertical. TANSTAAFL! It's no surprise that a full size quarter wave beats any loaded vertical, but I disagree that they all have dismal performance. The best 5 are less than a 1 dB difference (with the best being a mere 0.3 dB difference). The best 13 are under 6 dB, which is less than 1 S unit. Only 4 have a greater than 1 S unit difference. > Likewise, the horizontal antenna comparisons confirm the overall > superiority of a simple dipole over other horizontal types being > tested. Here, the worst is -3.78 db, which is only slightly over half an S unit, while a couple beat out the reference antenna. Yes, ok, one of those *is* a yagi; the other is the long buddipole. > A comparison of all tested horizontal and vertical antennas against > the half-wave horizontal dipole would have been interesting. I'm sure > it would have shown a very significant advantage of a horizontal > dipole over any vertical tested. I would also like to see a comparison between the horizontal and vertical antennas. I don't think the horizontal antenna would necessarily beat the vertical - it depends on a few variables, a couple big ones that come to mind being the height of the dipole and the vertical's counterpoise. Of course, what is best also depends on what takeoff angle you want. If you want a low takeoff angle for DX, I would argue that a vertical would be hard to beat, especially if you're not able to get a dipole up high enough. A low dipole is, of course, hard to beat for shorter distances. > compared to that of a single band dipole. That's why, for the > seven-band portable dipole that I put together, I use small, > lightweight, home-made PVC insulators with manually connected jumpers > around them to change the band of resonance. Neat idea! -- 73, Brian VE7NGR _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Mike Morrow-3
Mike,
The way I read the table, the MP1 and PAC-12 are both about 1/2 dB down from a quarter wave piece of wire and a single radial. Leigh WA5ZNU On Sun, 4 Jul 2004 6:49am, Mike Morrow wrote: > It confirms the very dismal performance of *all* those "popular" HF > short loading-coil verticals in comparison to the most simple, basic, > inexpensive quarter-wave vertical. 73, WA5ZNU Leigh _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Brian Mury-3
I haven't done "pedestrian mobile" like the "Packers" but I have used a
vertical with single "counterpoise" with a total length of 1/2 wave like that "reference vertical" they show on the web page would be on 20 meters. First, we ARE talking verticals now, and a vertical has about a 6 dB disadvantage over a horizontal, provided the horizontal is about 1/2 wave high! That's not likely to happen below 10 meters on a portable or pedestrian mobile setup, so it's a moot point here. That aside, what is interesting about a vertical with one horizontal counterpoise wire is that the counterpoise radiates as much as the antenna. Typical "ground-plane" arrangements provide a lot of cancellation of radiation from the "radials" since then are generally opposite each other and fed "in phase" (all connect to the same electrical point, not to out-of-phase currents like a dipole fed at the center). With only one counterpoise, there is no cancellation. That produces a lobe straight up for NVIS propagation from the counterpoise that is virtually as strong as the lower angle lobe. Also the antenna becomes fairly directional (in the direction of the counterpoise) which helps provide some gain to overcome the near-ground losses when hanging from a pedestrian <G>. That combination can be dynamite for what a H-F Pack operator wants - a great mix of radiation angles supporting ground wave and sky wave contacts. The only consideration seems to be that it will probably help to have the counterpoise sort of generally pointing in the direction of the other station for ground wave communications, although the "directivity" is going to be very broad. Also, with the counterpoise literally "on the ground" that high angle radiation will be greatly affected by the condition of the earth under it. Ron AC7AC -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Brian Mury Sent: Sunday, July 04, 2004 10:20 AM To: [hidden email] Subject: Re: [Elecraft] Antenna? On Sun, 2004-07-04 at 06:47, Mike Morrow wrote: > It confirms the very dismal performance of *all* those "popular" HF > short loading-coil verticals in comparison to the most simple, basic, > inexpensive quarter-wave vertical. TANSTAAFL! It's no surprise that a full size quarter wave beats any loaded vertical, but I disagree that they all have dismal performance. The best 5 are less than a 1 dB difference (with the best being a mere 0.3 dB difference). The best 13 are under 6 dB, which is less than 1 S unit. Only 4 have a greater than 1 S unit difference. >... -- 73, Brian VE7NGR _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Jimmy Lee-4
Brian Mury wrote:
>I would also like to see a comparison between the horizontal and >vertical antennas. I don't think the horizontal antenna would >necessarily beat the vertical - it depends on a few variables, a couple >big ones that come to mind being the height of the dipole and the >vertical's counterpoise. Hi Brian, HF verticals perform poorly without, as you mention above, a very good counterpoise or ground plane. In temporary portable installations, that is generally very difficult to obtain. But for a dipole, it's a non-issue altogether. I've never been able to get any vertical antenna (even a very expensive Australian-made dummy load) to perform within several s-units of a half-wave dipole that was up only about ten feet in side-by-side tests at a *temporary* site. The generalizations I make are simply based on what I've observed in several decades of tinkering with campsite antennas. They apply only to practical portable installations, not to the more optimally configured fixed vertical situation where observed performance may more likely reflect the theory. 73, Mike / KK5F _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Mike (and others)...
There's been some discussions on the HFPack list about a ground independent vertical design, published in the April 2004 issue of QST. The author, Brian Cake, KF2YN, describes a "C-Pole" loop antenna resembling an OCF (off-center fed) horizontal antenna, only wrapped in a loop. A tree branch about 18' off the ground is all that's needed to hoist the 20M version into the air. Feed is at ground level through a choke balun. EZNEC shows a low angle of radiation, and no radials/counterpoise, etc. are needed. Details for the 20M version may also be found: http://www.angelfire.com/tx4/netxqrpclub/ And the original article describing the background and 20 - 10M designs: http://www.arrl.org/members-only/tis/info/pdf/0404037.pdf 73, Steve aa8af -----Original Message----- HF verticals perform poorly without, as you mention above, a very good counterpoise or ground plane. In temporary portable installations, that is generally very difficult to obtain. But for a dipole, it's a non-issue altogether. _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Brian Mury-3
On Sun, 2004-07-04 at 10:20, Brian Mury wrote:
> It's no surprise that a full size quarter wave beats any loaded > vertical, but I disagree that they all have dismal performance. What I said and what I was thinking were not exactly the same. I meant to say that the antennas in the shootout don't all have dismal performance compared to the full size quarter wave reference antenna used. Compared to a full size quarter wave with a good counterpoise - well, that's a different question! -- 73, Brian VE7NGR _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Mike Morrow-3
Mike Morrow wrote:
>Brian Mury wrote: > > > >>I would also like to see a comparison between the horizontal and >>vertical antennas. I don't think the horizontal antenna would >>necessarily beat the vertical - it depends on a few variables, a couple >>big ones that come to mind being the height of the dipole and the >>vertical's counterpoise. >> >> > >Hi Brian, > >HF verticals perform poorly without, as you mention above, a very good counterpoise or ground plane. In temporary portable installations, that is generally very difficult to obtain. But for a dipole, it's a non-issue altogether. > >I've never been able to get any vertical antenna (even a very expensive Australian-made dummy load) to perform within several s-units of a half-wave dipole that was up only about ten feet in side-by-side tests at a *temporary* site. > > The nice thing about veritcals for backpacking is if you cannot find trees they still work. Additionally you can get away with almost no feed line if weight is a concern. As for the counterpoise situation, I find stringing wires on the groung to be much simpler than stringing them up in trees. I carry up to four 32' sections with me that form a counterpoise against the veritcal element and often I can elevate the groundplane for free (nearby scrub brush). Still not a "silver plated" back yard but it seems to suffice. Now the real advantage of all that wire is if I want a dipole, and can locate tree's, all I need do is add a feedpoint to the center and I have it. Personally, if I have the trees available I usually put up a full wave loop as it takes almost no extra effort and works very well. My best "vertical" experince involves a week of surfing on a 1 acre island in the S. Pacific. A 20' vertical over a sandy atoll with 4 wire counterpoise, 64' long. In a few days I had worked 40 countries on every continent . Of course this probably represents the best counterpoise one can achieve. another Brian - n6iz _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Jimmy Lee-4
Hi All,
I'm new to this list and Elecraft too - I've recently completed building a "loaded" KX1 #731. After building and aligning the KX1 with zero problems, I connected it to both my 130+ ft "slinky dipole" strung-up in the attic of our single-level home (with RG8X) and also my Cushcraft MA5V vertical (10-12-15-17-20) up around 33 feet at the base (also with RG8X). I was pleasantly surprised to hear the receiver come alive with signals on all three bands. The built-in antenna tuner reports: Slinky Dipole "CliffDweller II" 40m: 7055 - 2.1 Watts out, SWR 1.0 30m: 10107 - 1.8 Watts out, SWR 5.2 (relay chatter) 20m: 14065 - 3.0 Watts out, SWR 1.2 Cushcraft MA5V "Mini Vertical" 40m: 7055 - 2.1 Watts out, SWR 1.1 30m: 10107 - 4.3 Watts out, SWR 5.6 (relay chatter) (power out reading suspect) 20m: 14065 - 2.1 Watts out, SWR 1.0 Dummy Load (Oil-filled "Can-tenna") 40m: 7055 - 2.9 Watts out, SWR 1.0 30m: 10107 - 2.3 Watts out, SWR 1.0 20m: 14065 - 2.3 Watts out, SWR 1.0 (all using Lithium Batteries) Any thoughts regarding why the tuner has such a problem on 30m? Wow, what a great little rig! This is going to be fun. Elecraft is certainly a class act. 72 & 73 Doug N7BNT _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Doug, the feedline length may be a problem on 30m.
Try adding or subtracting 5 or 10 feet to it. 72 Stuart K5KVH _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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