Re: [Elecraft] 43' Vertical and the K2 tuner
Where Gotham stumbled badly was in promoting the fiction that radials weren't required on an (electrically) short vertical. To quote from Gotham's January 1959 QST ad: Are radials needed with a Gotham vertical? Answer: No, except in a few rare occasions. 99% of the installations are done without radials. That ad is disingenuous at best. Notice that the example given does not prove radials are not needed. It only claims that few people used them, and it fails to mention those who used them without radials, especially on the lower frequency bands, got the results anyone familiar with antenna theory would expect. The word abysmal comes to mind. Remember that back then it was still widely believed that a ground rod was a good RF ground, especially if one surrounded it with a trench filled with rock salt to make the earth more conductive. Gotham stepped farther over the edge in other ads, such as their December 1959 QST ad in which they trump the success of K6INI who reportedly worked DXCC using a Gotham V80 running 65 watts input (40 to 50 watts output) CW with 589/599 reports from every continent. The side panel clearly says with a big bullet No radials required. What they did not say was what bands K6INI made these contacts on or whether he had radials on his antenna. A 16 foot radiator isn't a terrible radiator on 20, 15 or 10 meters even with a poor ground. It was certainly better than a mobile whip on a car which many Hams were using to work DX in those days in the midst of the world's biggest sunspot cycle. Clearly, many Novices took Gotham at their implied word and attempted to use the V80 on 80 and 40 meters without radials, which was a disaster. There is a lesson in all of this: basic antenna theory has not changed since radio was invented. There have been no scientific breakthroughs in antennas since Hertz demonstrated a half-wave loop or Marconi figured out how to achieve synchronicity (resonance) with an electrically short antenna. All the work since has been applying different ways to achieve the best results, but always following the same basic rules. The ghost of Gotham lives in any manufacturer claiming a scientific breakthrough or magic from a small antenna. Ron AC7AC -Original Message- Steve and All, Well, not exactly! You remember those Gothams huh! I had one of them. Back in 1956 I bought a Gotham V80 when we first moved to New Mexico--no trees there like I had in Oregon! All the V80 consisted of was a long piece of aluminum and a loading coil! I don't remember how tall it was, but it may well have been something like 22 feet. It was base loaded, and not all that easy to use multi-band, particularly if you had it on the roof! It wasn't hard to make the decision to use it as a monoband vertical, and mine became a 20 meter vertical. I don't remember for sure, but I think the coil became superfluous! If I'd been smarter, I would have set it up like Jim Duffey suggested, although I don't remember anyone selling remote tuners back then. Dave W7AQK __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Where Gotham stumbled badly was in promoting the fiction that radials weren't required on an (electrically) short vertical. To quote from Gotham's January 1959 QST ad: Are radials needed with a Gotham vertical? Answer: No, except in a few rare occasions. 99% of the installations are done without radials. Now throw the then relatively new monimatch SWR meter into the mix. Add radials to the shortened base-fed vertical and watch line SWR increase. To many novices, the thinking is that if the SWR is better without radials, then why use them? Paul, W9AC __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Was it Gotham that used corrugated aluminum tubing? Seem to remember one antenna that we could never get the pieces apart. The corrugations caused too much binding. Nobody used Alumilox any such thing in those days. 73 de Brian/K3KO Ron D'Eau Claire wrote: Where Gotham stumbled badly was in promoting the fiction that radials weren't required on an (electrically) short vertical. To quote from Gotham's January 1959 QST ad: Are radials needed with a Gotham vertical? Answer: No, __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner [END of Thread]
Let's let this thread rest for now. :-) 73, Eric WA6HHQ Elecraft List Moderator __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Kok Chen wrote: http://homepage.mac.com/chen/Technical/Tuner/T3580.jpg I'll be glad to make the program available to anyone running Mac OS X 10.4 or newer. You can run the application to generate plots for other Before doing that, please consider not using JPEG for the images. This sort of image is blurred by JPEG encoding and normally compresses poorly. Once compressed with JPEG, it is not possible to get good compression by recompressing with appropriate algorithms. PNG is probably the best commonly available algorithm for this sort of data. JPEG is for continuous tone images with predominantly low spatial frequencies (people and many natural scenes). This image is discrete tone with most information in high spatial frequencies. -- David Woolley Emails are not formal business letters, whatever businesses may want. RFC1855 says there should be an address here, but, in a world of spam, that is no longer good advice, as archive address hiding may not work. -- David Woolley The Elecraft list is a forum for the discussion of topics related to Elecraft products and more general topics related ham radio List Guidelines http://www.elecraft.com/elecraft_list_guidelines.htm __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
On Mar 16, 2009, at 3/161:13 AM, David Woolley (E.L) wrote: Before doing that, please consider not using JPEG for the images. This sort of image is blurred by JPEG encoding and normally compresses poorly. Before making a statement like that, you might want to run the actual program, which uses a scalable Mac OS X Core Graphics context using scalable fonts. You can blow the NSView up so a single fulls stop is a full resolution disk an inch in diameter, if you want. The original capture using Grab.app was in TIFF and I had converted to a lower resolution JPEG so people would not have to download large files just to have a look, and JPEG is more universal than PNG so even old systems can view the output. Chen, W7AY __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
I used circa 45ft wire vertical with a few radials and k2 or k3. When connected directly or via a short run of TV line, the built-in tuner tunes down to 80 but 160m needs extra inductance. With BL1 balun any frequencies can be tuned but the balun gets hot. A better choice is to use an external tuner (without any balun) and connect the radio and the tuner by a balun. The balun made by wrapping 10 turns of RG174 on a toroid is excellent and does not heat at all. The performance with a few radials is excellent at beachside locations (160m DX!) and poor inland especially if ground mounted and with lots of obstructions. Ignacy, NO9E -- View this message in context: http://n2.nabble.com/43%27-Vertical-and-the-K2-tuner-tp2481408p2486236.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Elecraft] 43' Vertical and the K2 tuner
I remember one in particular, circa 1959. I had been licensed about a year and needed a tower. My then neighbor and Elmer the late Lee, W7UVR, had a 30' aluminum one laying in his yard and I asked him to donate it to me. He said that if I helped him install the ground radials under his V80 he would give me the tower. I naively said yes. It's necessary to set this up. Although the neighborhood was nice, one-acre lots then on the outskirts of Tucson, my family was working class and Lee was the recent beneficiary of a large trust fund. Why he remained in the neighborhood was a mystery to me, but nevertheless, he did. This is especially baffling considering that he had a noisy power line cutting across the cornet of his lot, so until Collins came out with their noise blanker for the 75A-4 sometime later, he couldn't hear anything. So he decide to go mobile. You can see THE mobile here: http://www.k0bg.com/gallery2/main.php?g2_itemId=1079 Clearly, Lee didn't do anything half-way. The same was true for the home station: A bank of built-in 6' relay racks populated with a common power supply and modulator and individual amplifiers for each band using push-pull 304TLs. Still, since he couldn't hear much, he got himself an appointment as an ARRL Official Bulletin Station, retransmitting W1AW announcements. Thus the need for a multi-band omni-directional antenna to augment the Christmas tree Telrex stack. When I entered this picture the vertical was standing and the transmission line was in place. I swear I'm not making this up, he was using rigid, air-insulated hardline filled with nitrogen. Not content to have a sloppy installation he wanted four-foot ground rods at the end of each radial so that the wire could be pulled tight and anchored to them. This is where I came in, he needed some to pound ground rods. I don't remember exactly how many I drove but I did it for days. As I remember, before he became wealthy he had designed BC stations, I suspect it was the classic 120. When I got done, we stretched and soldered the wire and he called in a landscaper to cover it all up with topsoil. I picked up my 30' tower and walked the two blocks home with it. --- On Sun, 3/15/09, Ken Kopp k...@rfwave.net wrote: From: Ken Kopp k...@rfwave.net Subject: [Elecraft] Elecraft] 43' Vertical and the K2 tuner To: Steve Ellington n...@carolina.rr.com, elecraft@mailman.qth.net Date: Sunday, March 15, 2009, 1:48 PM Steve, I thought of the Gotham, but doubted if anyone would remember (:-)) You must be OLD, like me! 73! Ken Kopp - K0PP __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Steve and All, Well, not exactly! You remember those Gothams huh! I had one of them. Back in 1956 I bought a Gotham V80 when we first moved to New Mexico--no trees there like I had in Oregon! All the V80 consisted of was a long piece of aluminum and a loading coil! I don't remember how tall it was, but it may well have been something like 22 feet. It was base loaded, and not all that easy to use multi-band, particularly if you had it on the roof! It wasn't hard to make the decision to use it as a monoband vertical, and mine became a 20 meter vertical. I don't remember for sure, but I think the coil became superfluous! If I'd been smarter, I would have set it up like Jim Duffey suggested, although I don't remember anyone selling remote tuners back then. Dave W7AQK - Original Message - From: Steve Ellington n...@carolina.rr.com To: elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 12:03 PM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner So we've rediscovered the Gotham V80 Vertical! Steve Ellington n...@carolina.rr.com - Original Message - From: Ron D'Eau Claire r...@cobi.biz To: elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 2:21 PM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner __ 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
[Elecraft] 43' Vertical and the K2 tuner
After the ice storm of 2009, I'm looking for an new antenna. I've been considering the 43' verticals by DXE,HyGain and MFJ. But I'm not sure if my K2 tuner will have the range needed. The DXE site has a warning about internal tuners. Anyone using a K2 and a 43' vertical ? how's it play ? Thanks in Advance - Jim (WB1DOG) __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
I use a Zero Five 43' vertical with my K3. Not sure if the K2 tuner is equivalent to the K3, but if it is, it should work well. As an example, I worked K5D on 160 through 20m with my Zero Five 43' vertical @ 100w. -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of James Apple Sent: Sunday, March 15, 2009 8:27 AM To: Elecraft@mailman.qth.net Subject: [Elecraft] 43' Vertical and the K2 tuner After the ice storm of 2009, I'm looking for an new antenna. I've been considering the 43' verticals by DXE,HyGain and MFJ. But I'm not sure if my K2 tuner will have the range needed. The DXE site has a warning about internal tuners. Anyone using a K2 and a 43' vertical ? how's it play ? Thanks in Advance - Jim (WB1DOG) __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Good Morning Jim ... The internal K2 tuner should have the range to match the 43 ft vertical. It is a wide-range tuner as opposed to the internal tuners on many rigs which are only good for tweaking antennas that are near resonance. You will, of course, have feedline losses due to high SWR with this system which can be noticeable on some bands. You will want to use low loss feedline and a proper current choke at the feedpoint. The resulting performance will depend heavily on the radial system used, and I would recommend a minimum of 32 untuned radials. Given attention to these details, you can expect good DX performance on 20, 30, 40 and 80 meters. On 17 meters and above the radiation angle will become higher than optimal for DX. The feedline loss issues can be resolved by using a remote tuner at the feedpoint. I'm doing this here using a CG-3000 tuner from Array Solutions. Works well with my K3, and I'm pleased with the performance of the antenna after installation of an adequate radial system. 73Craig AC0DS __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
If you use a rather long coax feedline, the K2 tuner might match it. Reason: The coax acts to reduce the apparant SWR by inducing considerable power loss. The 43' vertical is recent fad and it makes no sense at all. Virtually any trapped multiband vertical should easily outperform it. If you want to find out how it works, just run 43' for wire up a pole or a tree limb and see. Do this before investing $300 in a stick of aluminum. Also, you may be subjecting the little components in your K2's tuner to high currents when attempting to match that 43' stick on 80 and 160 meters. Impedances would be insanely low! Recommend using a remote tuner at the antenna's base, forget the so called balun/unun or a different antenna. 73 Steve Ellington n...@carolina.rr.com - Original Message - From: James Apple wb1...@gmail.com To: Elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 9:26 AM Subject: [Elecraft] 43' Vertical and the K2 tuner After the ice storm of 2009, I'm looking for an new antenna. I've been considering the 43' verticals by DXE,HyGain and MFJ. But I'm not sure if my K2 tuner will have the range needed. The DXE site has a warning about internal tuners. Anyone using a K2 and a 43' vertical ? how's it play ? Thanks in Advance - Jim (WB1DOG) __ 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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.13/2001 - Release Date: 03/14/09 06:54:00 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
The 43' vertical is recent fad and it makes no sense at all. Virtually any trapped multiband vertical should easily outperform it. Steve, I thought the same until I read this: http://vk1od.net/antenna/multibandunloadedvertical/ According to the author, the so-called magic of the 43-foot length is that radiation resistance remains quite high across the HF spectrum and thus, system losses are minimized. Compared to a 33-foot vertical, system losses are much lower across the spectrum. But to your point, a trapped multi-band vertical can offer similar performance. Personally, I think the negativity associated with trap loss in multi-band antennas is grossly overblown. Other systematic losses mask what little loss exists in most trapped antenna designs. Anyway, not sure how valid all this data really is, but the data presented is interesting Paul, W9AC __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
But note that for the 43' mast they use an autotuner located at the base of the mast, no coax losses involved. For the 33' mast they use ~50' of various pieces of coax with the associated losses. This a very biased comparison. If you are going to use a non-trapped, and hence non-resonant, vertical it is best to put the tuner at the base of the mast. Otherwise the coax losses will eat up a fair amount of the available power, even for a 43' mast (although they don't tell you this). 73 de dave ab9ca/4 Paul Christensen wrote: The 43' vertical is recent fad and it makes no sense at all. Virtually any trapped multiband vertical should easily outperform it. Steve, I thought the same until I read this: http://vk1od.net/antenna/multibandunloadedvertical/ According to the author, the so-called magic of the 43-foot length is that radiation resistance remains quite high across the HF spectrum and thus, system losses are minimized. Compared to a 33-foot vertical, system losses are much lower across the spectrum. But to your point, a trapped multi-band vertical can offer similar performance. Personally, I think the negativity associated with trap loss in multi-band antennas is grossly overblown. Other systematic losses mask what little loss exists in most trapped antenna designs. Anyway, not sure how valid all this data really is, but the data presented is interesting Paul, W9AC __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Back to the original question about using the K2's or K3's tuner on this antennaFigure 4. in that link shows the impedance of the antenna to be less than 10 ohms below 5 mHz and around 1 ohm on 160M. Factor the 1:4 balun in and that divides the Z by 4. So we end up with an impedance of less than 2 ohms presented to the K2's tuner. Open the windows and let the smoke out please. Steve Ellington n...@carolina.rr.com - Original Message - From: Paul Christensen w...@arrl.net To: Steve Ellington n...@carolina.rr.com; Elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 10:07 AM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner The 43' vertical is recent fad and it makes no sense at all. Virtually any trapped multiband vertical should easily outperform it. Steve, I thought the same until I read this: http://vk1od.net/antenna/multibandunloadedvertical/ According to the author, the so-called magic of the 43-foot length is that radiation resistance remains quite high across the HF spectrum and thus, system losses are minimized. Compared to a 33-foot vertical, system losses are much lower across the spectrum. But to your point, a trapped multi-band vertical can offer similar performance. Personally, I think the negativity associated with trap loss in multi-band antennas is grossly overblown. Other systematic losses mask what little loss exists in most trapped antenna designs. Anyway, not sure how valid all this data really is, but the data presented is interesting Paul, W9AC No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.13/2001 - Release Date: 03/14/09 06:54:00 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Steve Ellington wrote: Back to the original question about using the K2's or K3's tuner on this antennaFigure 4. in that link shows the impedance of the antenna to be less than 10 ohms below 5 mHz and around 1 ohm on 160M. Factor the 1:4 balun in and that divides the Z by 4. So we end up with an impedance of less than 2 ohms presented to the K2's tuner. Open the windows and let the smoke out please. I modeled a plain 43' vertical in EZNEC. Fed with 50-ohm line, the SWR on 40 meters is a bit less than 10:1; on 80 it's nearly 100:1. (11.1 - j232). It would be a dummy load on 80. Some of these antennas (like the Array Solutions mentioned) include baluns or transformers. My guess is that the large amount of reactance would increase losses in such a device. A tuner at the base would be the way to go. But keep in mind that you still need a good local ground system as well as decent ground conductivity within a few wavelengths for reasonable performance. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
That information in the site Paul referenced, as it relates to radiators, is also available in just about any antenna design handbook printed since the 1930's, so I'd trust it. The author does mention that the angle of radiation is strongly affected by the length of the antenna. That's also well documented. In a vertical, the main lobe rises quickly above the horizon as the antenna passes 5/8 wavelengths tall. A little rise in angle is unnoticeable in the real world since everything radiated by a vertical below about 15 or 20 degrees elevation is lost to ground absorption (unless one is sitting in the middle of the ocean). So 43 feet tall is not optimum for 10 meters but is ideal on 20 meters. There's actually an advantage in lower angle radiation to extending a vertical beyond 1/4 wavelength up to 5/8 wavelength. As the length approaches 5/8 wavelength, the familiar donut pattern is squashed with more power radiated at the lower angles while less is radiated at higher angles. That is, the donut pattern starts to resemble a fat disk. However, when one exceeds 5/8 wavelength the pattern quickly breaks up with much of the energy in higher-angle lobes. As the author notes, ground losses are the major issue. One resistor is the radiation resistance of the antenna and the other resistor is the ground resistance. Applying Ohm's law to series resistances shows that the most power is dissipated in the larger valued resistor. So you want the largest resistance in the system to be the radiation resistance. Ideally, you'd use a 1/2 wavelength radiator since that presents the largest radiation resistance but, obviously, such a radiator arranged vertically would have very poor low-angle radiation. When considering ground losses, think of two resistors in series with current (RF) flowing through them. A 1/4 wave vertical has a radiation resistance of about 35 ohms. That resistance drops very quickly as the antenna becomes shorter. A 1/8 wavelength radiator, for example, has a radiation resistance is about 7 ohms and 1/16 wave is under 2 ohms. It's very easy for a compromise ground such as used by many Hams to show a resistance of 200 or 300 ohms. That's why many *short* vertical installations have an efficiency of only a few percent, throwing almost all the RF energy away heating the earth. On the other hand, a 1/2 wave radiator with its very high radiation resistance, perhaps in the 2000 to 3000 ohm range, is a very efficient radiator, even with a poor or virtually no ground. But, as noted, a 1/2 wave end-fed vertical has an very undesirable radiation pattern. (Of course if it's center fed and oriented vertically, the familiar donut pattern is preserved, but not if it's end fed against a ground.) The author seems to be focused on how to feed a vertical efficiently across a range of frequencies. That is a big challenge if one doesn't want to put an active matching network at the feed point of the antenna. (Such active matching networks are commonly used in multi-band vertical installations commercially, such as on ships.) As the author notes, there are added losses since all matching networks have some losses. The more elements - inductors especially - the more losses. He states his figures do not include those added losses. The more common approach is to use a trap vertical. The traps divide the radiator into 1/4 wavelength segments on the various bands so it always looks like a common 1/4 wave vertical to the feed line. That's quite easy to match for a consistently low SWR on those bands for which the traps are designed. The disadvantages of a trap vertical (or any trap antenna) is that the traps add ohmic losses to the system and, most important, the antenna always shows a low impedance at the feed point. That low impedance requires a decent ground system to avoid most of the RF heating the earth'. Good engineering has always been, IMO, not a matter of making things perfect, but a matter of managing the compromises for the best results given the limitations imposed. Nowhere is that more obvious than in an antenna system. Ron AC7AC __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
We just had a heated exchange about these antennas on another reflector. Keep in mind that it is a compromise antenna. 43 feet is really not magical to any band that I know of. You still need a good radial system etc. From what I have read the tuner at the base would be much more efficient and use a good quality coax. I would be curious to see how a BigIR or even a Hy-tower compared to the 43 ft verticals. I was surprised to read that W5OV was able to match it with the K3 tuner. I think that speaks volumes for the tuner in the K3. I will have to play with my tuner a bit more. Most of my antennas have good swr except for the 40m beam in the extreme lower cw sections and the K3 tunes this fine but we are talking about 2 to 2.5 to 1 max, not 100:1 A slip of the foot you may soon recover, but a slip of the tongue you may never get over. Ben Franklin -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of James Apple Sent: Sunday, March 15, 2009 7:27 AM To: Elecraft@mailman.qth.net Subject: [Elecraft] 43' Vertical and the K2 tuner After the ice storm of 2009, I'm looking for an new antenna. I've been considering the 43' verticals by DXE,HyGain and MFJ. But I'm not sure if my K2 tuner will have the range needed. The DXE site has a warning about internal tuners. Anyone using a K2 and a 43' vertical ? how's it play ? Thanks in Advance - Jim (WB1DOG) __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Paul and All, This is very interesting! Thanks for bringing that article by VK1OD to our attention. I think I agree with you about trap losses. I have used a Cushcraft R7, and now an R8, for years with surprisingly good results. What appealed to me about both of these models is that they emulate a 1/2 wave antenna, thus making radials more or less unnecessary. These antennas only cover 40 and up however. What now intrigues me about the 43 ft. antenna is connected to some comments made to me by Jim Duffey, KK6MC (Dr. Megacycle) when he visited here some time ago. I think most of you are familiar with Jim, and respect (as I do) his technical expertise. Anyway, Jim suggested that I might be even better off with a 22 ft. vertical on my roof, with as many radials as I could reasonably lay out. He said I should also use a remote tuner and balanced feedline. Jim felt it would perform adequately on 40 meters, and better as you go up. I believe he said the magic about 22 feet was to try and keep the radiation angle from getting too high on the higher bands. So, now I'm wondering if a 43 ft. antenna would bring 80 meters, and apparently 160 meters, into play under more or less the same concept that Jim was espousing. He didn't really mention that the 22 ft. version might get you on 80, so maybe not, but the mathematical relationship sure has me wondering. Probably I'm extrapolating his comments incorrectly. I think Jim does monitor this reflector, so maybe he will jump in and make some comments. I will probably pass that article to him though, and see if I can prod him for some insight. By the way, I'm guessing that if you could roof mount, or otherwise elevate the 43 foot version, you might not have to worry quite so much about having so many radials. Anyway, this motivates me to do a little digging! Dave W7AQK - Original Message - From: Paul Christensen w...@arrl.net To: Steve Ellington n...@carolina.rr.com; Elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 7:07 AM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner The 43' vertical is recent fad and it makes no sense at all. Virtually any trapped multiband vertical should easily outperform it. Steve, I thought the same until I read this: http://vk1od.net/antenna/multibandunloadedvertical/ According to the author, the so-called magic of the 43-foot length is that radiation resistance remains quite high across the HF spectrum and thus, system losses are minimized. Compared to a 33-foot vertical, system losses are much lower across the spectrum. But to your point, a trapped multi-band vertical can offer similar performance. Personally, I think the negativity associated with trap loss in multi-band antennas is grossly overblown. Other systematic losses mask what little loss exists in most trapped antenna designs. Anyway, not sure how valid all this data really is, but the data presented is interesting Paul, W9AC __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Mike and All, I'm not all that surprised that W5OV was able to get a match using his K3, although I'm not sure exactly how severe the mismatch is. It has to be pretty far off though. Using my K3, with its built-in ATU, I am able to get a 1:1 match on 80 meters using my R8 vertical, which isn't supposed to go lower than 40 meters. I can also get a match that is better than 2:1 on 160. Obviously though, the efficiency of this antenna on those bands is pretty lousy. I really don't operate on 160, except I did work VP6DX on both SSB and CW with this arrangement. Their beverages did all the work though I'm sure. Nevertheless, the K3's ATU is very good! I haven't tried the same test with my K2 and it's built-in ATU, but that tuner is very good also. I just don't know if it's quite as good as the K3's. The ATU in my Orion II will also match the R8 on 80 meters, but just about every other rig I own, or have owned, with a built in ATU, would not come close to doing this. I have a Kenwood TS-480 and a Yaesu FT-1000 Mark V, neither of which could do that. The Mark V won't even allow me to cover all of 40 meters, but the K3 does it with ease. Having said all of this, I'd be very cautious about big excursions with the K3 or K2 built-in ATU's. I'd sure turn the power down a lot before even trying. Clearly though, not all built-in ATU's are equal! Dave W7AQK - Original Message - From: W0MU Mike Fatchett w...@w0mu.com To: 'James Apple' wb1...@gmail.com; Elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 9:16 AM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner We just had a heated exchange about these antennas on another reflector. Keep in mind that it is a compromise antenna. 43 feet is really not magical to any band that I know of. You still need a good radial system etc. From what I have read the tuner at the base would be much more efficient and use a good quality coax. I would be curious to see how a BigIR or even a Hy-tower compared to the 43 ft verticals. I was surprised to read that W5OV was able to match it with the K3 tuner. I think that speaks volumes for the tuner in the K3. I will have to play with my tuner a bit more. Most of my antennas have good swr except for the 40m beam in the extreme lower cw sections and the K3 tunes this fine but we are talking about 2 to 2.5 to 1 max, not 100:1 A slip of the foot you may soon recover, but a slip of the tongue you may never get over. Ben Franklin -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of James Apple Sent: Sunday, March 15, 2009 7:27 AM To: Elecraft@mailman.qth.net Subject: [Elecraft] 43' Vertical and the K2 tuner After the ice storm of 2009, I'm looking for an new antenna. I've been considering the 43' verticals by DXE,HyGain and MFJ. But I'm not sure if my K2 tuner will have the range needed. The DXE site has a warning about internal tuners. Anyone using a K2 and a 43' vertical ? how's it play ? Thanks in Advance - Jim (WB1DOG) __ 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 __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Dave, If you look at the LB Cebik information, he has long recommended 44 foot dipoles as a back-up antenna for 40 through 10 meters and 88 foot dipoles for 80 through 20. The main reason for his recommendation is that the radiation pattern does not break up into lobes over that range of frequencies, and all the radiation is broadside to the antenna wire. Now, take that dipole and stand it on end - the radiation pattern will be low to the earth. As a second step, remove the lower portion of the antenna and install radials (22 or 44 ft long) to balance out the vertical section. If the radials are run in opposing directions, any radiation from them will cancel leaving all the radiated power from the vertical element, and it will be at a low angle when operated within the frequency range that keeps the radiation pattern in single lobe (below 10m for the 22 ft vertical and below 20m for the 44 ft vertical). If the vertical element is mounted well above the ground, 4 radials (2 pair oriented in opposing directions) should be sufficient, but if ground mounted, a lot of radials are needed to form a ground screen. An antenna of this nature will not have an impedance suitable for feeding with coax. A remote auto-tuner or an L section designed for each band will be needed at the base to provide a suitable match or the coax. If the feedpoint is transformed to something coax can easily match, most all the power will be delivered to the radiator and the feedline loss will be small, but if directly fed with coax, the losses can be rather high - just how high depends on the feedline length. 73, Don W3FPR dyarnes wrote: Paul and All, This is very interesting! Thanks for bringing that article by VK1OD to our attention. I think I agree with you about trap losses. I have used a Cushcraft R7, and now an R8, for years with surprisingly good results. What appealed to me about both of these models is that they emulate a 1/2 wave antenna, thus making radials more or less unnecessary. These antennas only cover 40 and up however. What now intrigues me about the 43 ft. antenna is connected to some comments made to me by Jim Duffey, KK6MC (Dr. Megacycle) when he visited here some time ago. I think most of you are familiar with Jim, and respect (as I do) his technical expertise. Anyway, Jim suggested that I might be even better off with a 22 ft. vertical on my roof, with as many radials as I could reasonably lay out. He said I should also use a remote tuner and balanced feedline. Jim felt it would perform adequately on 40 meters, and better as you go up. I believe he said the magic about 22 feet was to try and keep the radiation angle from getting too high on the higher bands. So, now I'm wondering if a 43 ft. antenna would bring 80 meters, and apparently 160 meters, into play under more or less the same concept that Jim was espousing. He didn't really mention that the 22 ft. version might get you on 80, so maybe not, but the mathematical relationship sure has me wondering. Probably I'm extrapolating his comments incorrectly. I think Jim does monitor this reflector, so maybe he will jump in and make some comments. I will probably pass that article to him though, and see if I can prod him for some insight. By the way, I'm guessing that if you could roof mount, or otherwise elevate the 43 foot version, you might not have to worry quite so much about having so many radials. Anyway, this motivates me to do a little digging! Dave W7AQK - Original Message - From: Paul Christensen w...@arrl.net To: Steve Ellington n...@carolina.rr.com; Elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 7:07 AM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner The 43' vertical is recent fad and it makes no sense at all. Virtually any trapped multiband vertical should easily outperform it. Steve, I thought the same until I read this: http://vk1od.net/antenna/multibandunloadedvertical/ According to the author, the so-called magic of the 43-foot length is that radiation resistance remains quite high across the HF spectrum and thus, system losses are minimized. Compared to a 33-foot vertical, system losses are much lower across the spectrum. But to your point, a trapped multi-band vertical can offer similar performance. Personally, I think the negativity associated with trap loss in multi-band antennas is grossly overblown. Other systematic losses mask what little loss exists in most trapped antenna designs. Anyway, not sure how valid all this data really is, but the data presented is interesting Paul, W9AC __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Dr. Megacycle has it on the head with the length: 22 feet is 5/8 wave on 10 meters. Good commercial automatic tuners will feed such an antenna all the way down below 80 meters. The SGC-230 is commonly used on ships feeding a 23 foot whip all the way down to the emergency SSB frequency at 2182 kHz. Many published tests have shown that getting the radials away from the ground is *very* beneficial and may well outweigh the loss of efficiency in reducing the height of the vertical. Back in '87, A. M. Christman, KB8I, published the results of studies he conducted in the Proceedings of the Third Annual Review of Progress in Applied Computational Electromagnetics for the U.S. Naval Postgraduate School, which he later summarized for hams in an article in the Aug 1988 issue of QST. That article is available to ARRL members on their web site. It gives numerous examples of the improvements to be expected as various counterpoise systems are used above ground. Let me point out to anyone interested enough to read my previous post that I misspoke. It was kindly brought to my attention by Arnie, PA3A, who observed I said a half wave radiator has a high radiation resistance when I meant to say it had a high feed point impedance. My conclusion was correct as to the benefit of a high feed point impedance, but there's a huge difference between the resistive value of the feed point impedance and radiation resistance! Ron AC7AC __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
I don't have the L and C values for the K2 tuner, but if you want to see what impedances can be transformed from 50 ohms using the KAT100, you can take a look at these images: http://homepage.mac.com/chen/Technical/Tuner/T3580.jpg http://homepage.mac.com/chen/Technical/Tuner/T14080.jpg http://homepage.mac.com/chen/Technical/Tuner/T28080.jpg The green dots are for transceiver : ( series L : shunt C ) : antenna. The blue dots are for transceiver : ( shunt C : series R ) : antenna. The dots shown are the impedances that the antenna sees if the transceiver's output impedance is 50 ohms. So, antenna impedances that the tuner will tune is just the conjugate of the points that you see on the charts (i.e., just flip the charts upside down). As the file name indicates, they are charts for 3.58 MHz, 14.080 MHz and 28.080 MHz (RTTY frequencies, naturally :-). The application that generates the charts above was originally written to test a Smith Chart library that I wrote for Cocoa. (The library was subsequently used in cocoaNEC and by K1GQ in his cocoaVNA program, an application for the TAPR/Ten-Tec VNA). I'll be glad to make the program available to anyone running Mac OS X 10.4 or newer. You can run the application to generate plots for other frequencies. The Xcode sources are also available in case you have a different set of L and C values (than used in the KAT100) that you want to try out. 73 Chen, W7AY __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
On Mar 15, 2009, at 11:35 AM, Kok Chen wrote: The blue dots are for transceiver : ( shunt C : series R ) : antenna. Oops, I meant transceiver : ( shunt C : series L ) : antenna. 73 Chen, W7AY __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
So we've rediscovered the Gotham V80 Vertical! Steve Ellington n...@carolina.rr.com - Original Message - From: Ron D'Eau Claire r...@cobi.biz To: elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 2:21 PM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner Dr. Megacycle has it on the head with the length: 22 feet is 5/8 wave on 10 meters. Good commercial automatic tuners will feed such an antenna all the way down below 80 meters. The SGC-230 is commonly used on ships feeding a 23 foot whip all the way down to the emergency SSB frequency at 2182 kHz. Many published tests have shown that getting the radials away from the ground is *very* beneficial and may well outweigh the loss of efficiency in reducing the height of the vertical. Back in '87, A. M. Christman, KB8I, published the results of studies he conducted in the Proceedings of the Third Annual Review of Progress in Applied Computational Electromagnetics for the U.S. Naval Postgraduate School, which he later summarized for hams in an article in the Aug 1988 issue of QST. That article is available to ARRL members on their web site. It gives numerous examples of the improvements to be expected as various counterpoise systems are used above ground. Let me point out to anyone interested enough to read my previous post that I misspoke. It was kindly brought to my attention by Arnie, PA3A, who observed I said a half wave radiator has a high radiation resistance when I meant to say it had a high feed point impedance. My conclusion was correct as to the benefit of a high feed point impedance, but there's a huge difference between the resistive value of the feed point impedance and radiation resistance! Ron AC7AC __ 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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.13/2001 - Release Date: 03/14/09 06:54:00 __ 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
[Elecraft] Elecraft] 43' Vertical and the K2 tuner
Steve, I thought of the Gotham, but doubted if anyone would remember (:-)) You must be OLD, like me! 73! Ken Kopp - K0PP __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Paul, According to the author, the so-called magic of the 43-foot length is that radiation resistance remains quite high across the HF spectrum and thus, system losses are minimized. Unfortunately, that information is demonstrably wrong. The radiation resistance varies from very low on 160 to modest values on 10 meters. The feedpoint IMPEDANCE (complex) remains high across all of the amateur bands because except for 10 meters where the antenna is approximately 5 quarter wave long the antenna is not resonant (+/- j0) on any band. The mistake of equating feed impedance with radiation resistance is one of the issues that erroneously result in claims of greater efficiency for folded monopoles on 80 and 160 meters. The 43' vertical is simply a convenient length to feed in that it does not present a high feed impedance on any amateur band (although it is highly reactive with a low real part on 80 and 160). One would be far better with a 58' (80 - 30 meters) or 88' (160 - 40 meters) vertical with matching in the form of switched networks or an auto tuner at the base than with the magic 43' vertical fed with 50 Ohm coax and tuner in the shack. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Paul Christensen Sent: Sunday, March 15, 2009 10:08 AM To: Steve Ellington; Elecraft@mailman.qth.net Subject: Re: [Elecraft] 43' Vertical and the K2 tuner The 43' vertical is recent fad and it makes no sense at all. Virtually any trapped multiband vertical should easily outperform it. Steve, I thought the same until I read this: http://vk1od.net/antenna/multibandunloadedvertical/ According to the author, the so-called magic of the 43-foot length is that radiation resistance remains quite high across the HF spectrum and thus, system losses are minimized. Compared to a 33-foot vertical, system losses are much lower across the spectrum. But to your point, a trapped multi-band vertical can offer similar performance. Personally, I think the negativity associated with trap loss in multi-band antennas is grossly overblown. Other systematic losses mask what little loss exists in most trapped antenna designs. Anyway, not sure how valid all this data really is, but the data presented is interesting Paul, W9AC __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
déjà vu all over again. I have worked Japan on my oil filled dummy load on 10m during the peak. That does not equate to a great antenna. You can tune just about anything does that mean it is a great or efficient radiator, no. If it is the best you got great. If you were using an ISOLOOP sure the 43ft antenna will probably sound pretty dog gone great. If you want to be humbled, visit a local contest superstation with big ole stacks or 4 squares. Most of us can't build a superstation so we have to make compromises. All that really matters is that you are happy with what you have. A slip of the foot you may soon recover, but a slip of the tongue you may never get over. Ben Franklin -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Steve Ellington Sent: Sunday, March 15, 2009 1:04 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] 43' Vertical and the K2 tuner So we've rediscovered the Gotham V80 Vertical! Steve Ellington n...@carolina.rr.com - Original Message - From: Ron D'Eau Claire r...@cobi.biz To: elecraft@mailman.qth.net Sent: Sunday, March 15, 2009 2:21 PM Subject: Re: [Elecraft] 43' Vertical and the K2 tuner Dr. Megacycle has it on the head with the length: 22 feet is 5/8 wave on 10 meters. Good commercial automatic tuners will feed such an antenna all the way down below 80 meters. The SGC-230 is commonly used on ships feeding a 23 foot whip all the way down to the emergency SSB frequency at 2182 kHz. Many published tests have shown that getting the radials away from the ground is *very* beneficial and may well outweigh the loss of efficiency in reducing the height of the vertical. Back in '87, A. M. Christman, KB8I, published the results of studies he conducted in the Proceedings of the Third Annual Review of Progress in Applied Computational Electromagnetics for the U.S. Naval Postgraduate School, which he later summarized for hams in an article in the Aug 1988 issue of QST. That article is available to ARRL members on their web site. It gives numerous examples of the improvements to be expected as various counterpoise systems are used above ground. Let me point out to anyone interested enough to read my previous post that I misspoke. It was kindly brought to my attention by Arnie, PA3A, who observed I said a half wave radiator has a high radiation resistance when I meant to say it had a high feed point impedance. My conclusion was correct as to the benefit of a high feed point impedance, but there's a huge difference between the resistive value of the feed point impedance and radiation resistance! Ron AC7AC __ 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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.13/2001 - Release Date: 03/14/09 06:54:00 __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
A few years ago, I was really on the 5/8 vertical bandwagon. I thought it was the cat's meow. The problem was that real world A/B testing did NOT show it to be any better than a 1/4 wave vert. I had a 5/8 wave vert for 15 meters. Ground mounted over 16 radials. An ATU at the base took care of the small impedance mismatch and RG-213 carried the signal to the rig. Hot stuff - or so I thought. I also had a 1/4 wave ground plane (4 radials) on the roof of my single story house. It was fed with RG-58. I spent a lot of time with an A/B switch listening to both antennas. You'd think the 5/8 with it's mondo low-angle radiation pattern would walk all over the 1/4 wave but it DID NOT. DX signals as the band was just opening or closing were sometimes stronger on the 5/8, other times on the 1/4. There was no clear winner. It was years before I found the answer. Apparently, that wonderful low angle radiation that we want out of the 5/8 wave antenna depends HEAVILY on the ground conductivity many, many wavelengths away from the antenna. Far out of the reach of any ground radial system, poor soil conductivity is sucking the low angle radiation down to near zero. Sure, over salt water it is fabulous, but for the vast majority, it just doesn't pan out that way. So, for normal soil, it seems the best height is something less than 1/2 wave. I run a 33' vertical with a Hustler 80M resonator on top. It resonates on 80 and 40 and does pretty well on those two bands. It also delivers the goods on 30 meters due to the remote tuner. On 20 meters and higher it isn't really all that impressive. - Keith N1AS - - K3 711 - -Original Message- From: elecraft-boun...@mailman.qth.net on behalf of James Apple Sent: Sun 3/15/2009 9:26 AM To: Elecraft@mailman.qth.net Subject: [Elecraft] 43' Vertical and the K2 tuner After the ice storm of 2009, I'm looking for an new antenna. I've been considering the 43' verticals by DXE,HyGain and MFJ. But I'm not sure if my K2 tuner will have the range needed. The DXE site has a warning about internal tuners. Anyone using a K2 and a 43' vertical ? how's it play ? Thanks in Advance - Jim (WB1DOG) __ 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 __ 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
Re: [Elecraft] 43' Vertical and the K2 tuner
Keith, in theory the 5/8 vertical should be 3 db stronger than the 1/4 vertical installed in the same position. A ground plane on top of a house could easily be as good or better than a 5/8 wave ground mounted and radiating into the side of the house and some trees. 3 db is about 1/2 S unit anyway, so it will not be a large difference. You are correct about the far field conductivity being very important in how a vertical antenna will play, whether it is mounted on top of a tower or house or ground mounted. The radials are most important to bring up the radiation efficiency, the far field is most important for the take off angle. The 43 foot vertical will have a higher radiation resistance than a shorter vertical for all bands, making it easier to get the efficiency up. It will still be lower than 50 ohms for 160, 80 and 60 meters, about 50 ohms for 40 and higher for the upper frequencies. I don't have one because I have a 3 element SteppIR with the 30/40 dipole trombone at 21 meters. I don't think the 43 foot vertical will play as well, but they do play well. I have worked several of the Zero-Five offering and they all play well. I would expect the DXE, Hygain and MFJ to play well also, but they are newer and I don't know anyone who has one. All still need a good ground plane and will play much better with conductive soil. Willis 'Cookie' Cooke K5EWJ --- On Sun, 3/15/09, Darwin, Keith keith.dar...@goodrich.com wrote: From: Darwin, Keith keith.dar...@goodrich.com Subject: Re: [Elecraft] 43' Vertical and the K2 tuner To: James Apple wb1...@gmail.com, Elecraft@mailman.qth.net Date: Sunday, March 15, 2009, 2:39 PM A few years ago, I was really on the 5/8 vertical bandwagon. I thought it was the cat's meow. The problem was that real world A/B testing did NOT show it to be any better than a 1/4 wave vert. I had a 5/8 wave vert for 15 meters. Ground mounted over 16 radials. An ATU at the base took care of the small impedance mismatch and RG-213 carried the signal to the rig. Hot stuff - or so I thought. I also had a 1/4 wave ground plane (4 radials) on the roof of my single story house. It was fed with RG-58. I spent a lot of time with an A/B switch listening to both antennas. You'd think the 5/8 with it's mondo low-angle radiation pattern would walk all over the 1/4 wave but it DID NOT. DX signals as the band was just opening or closing were sometimes stronger on the 5/8, other times on the 1/4. There was no clear winner. It was years before I found the answer. Apparently, that wonderful low angle radiation that we want out of the 5/8 wave antenna depends HEAVILY on the ground conductivity many, many wavelengths away from the antenna. Far out of the reach of any ground radial system, poor soil conductivity is sucking the low angle radiation down to near zero. Sure, over salt water it is fabulous, but for the vast majority, it just doesn't pan out that way. So, for normal soil, it seems the best height is something less than 1/2 wave. I run a 33' vertical with a Hustler 80M resonator on top. It resonates on 80 and 40 and does pretty well on those two bands. It also delivers the goods on 30 meters due to the remote tuner. On 20 meters and higher it isn't really all that impressive. - Keith N1AS - - K3 711 - -Original Message- From: elecraft-boun...@mailman.qth.net on behalf of James Apple Sent: Sun 3/15/2009 9:26 AM To: Elecraft@mailman.qth.net Subject: [Elecraft] 43' Vertical and the K2 tuner After the ice storm of 2009, I'm looking for an new antenna. I've been considering the 43' verticals by DXE,HyGain and MFJ. But I'm not sure if my K2 tuner will have the range needed. The DXE site has a warning about internal tuners. Anyone using a K2 and a 43' vertical ? how's it play ? Thanks in Advance - Jim (WB1DOG) __ 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 __ 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 __ 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
