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Best HF Vertical
I know I can go to eham.com but I like the advice on rraa better. I also
know that this question is somewhat subjective, but if you will, please indulge. :-) What is flat out the best vertical HF antenna in your opinion and why? Thanks in advance. west AF4GC |
#2
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Best HF Vertical
"west" wrote in message news:280Kh.1399$Eg4.1163@trnddc03... I know I can go to eham.com but I like the advice on rraa better. I also know that this question is somewhat subjective, but if you will, please indulge. :-) What is flat out the best vertical HF antenna in your opinion and why? Thanks in advance. west AF4GC One with a good radial system. |
#3
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Best HF Vertical
"west" wrote in message news:280Kh.1399$Eg4.1163@trnddc03... I know I can go to eham.com but I like the advice on rraa better. I also know that this question is somewhat subjective, but if you will, please indulge. :-) What is flat out the best vertical HF antenna in your opinion and why? Thanks in advance. west AF4GC IMHO: Take a look at the steppir verticals http://www.steppir.com/ No traps, coils, capacitors or linear loading of any kind. Full continuous coverage, including WARC bands-without compromise! 2000 W PEP Rating. Used on several DXpeditions with rave reviews That's the one I would buy if I could put in a good ground radial system - but I have no room for radials. So don't own one, a friend does and for what is worth he claims it is the best vertical he has ever owned over 30 years including, Butternut, Cushcraft, Hustler, Hy-Gain, etc But the steppir's are pricey $595 and $695 Good luck CL |
#4
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Best HF Vertical
On 14 Mar, 18:50, "Caveat Lector" wrote:
"west" wrote in message news:280Kh.1399$Eg4.1163@trnddc03... I know I can go to eham.com but I like the advice on rraa better. I also know that this question is somewhat subjective, but if you will, please indulge. :-) What is flat out the best vertical HF antenna in your opinion and why? Thanks in advance. west AF4GC IMHO: Take a look at the steppir verticals http://www.steppir.com/ No traps, coils, capacitors or linear loading of any kind. Full continuous coverage, including WARC bands-without compromise! 2000 W PEP Rating. Used on several DXpeditions with rave reviews That's the one I would buy if I could put in a good ground radial system - but I have no room for radials. So don't own one, a friend does and for what is worth he claims it is the best vertical he has ever owned over 30 years including, Butternut, Cushcraft, Hustler, Hy-Gain, etc But the steppir's are pricey $595 and $695 Good luck CL A vertical dipole fed in the center Art |
#5
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Best HF Vertical
There is such a thing? ;O
Well, my only experience with an HF vertical is the Outbacker on my truck. Works A-OK on 40M and up, but seems a little weak on 80M (which doesn't really surprise me!). Scott N0EDV west wrote: I know I can go to eham.com but I like the advice on rraa better. I also know that this question is somewhat subjective, but if you will, please indulge. :-) What is flat out the best vertical HF antenna in your opinion and why? Thanks in advance. west AF4GC |
#6
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Best HF Vertical
west wrote:
I know I can go to eham.com but I like the advice on rraa better. I also know that this question is somewhat subjective, but if you will, please indulge. :-) What is flat out the best vertical HF antenna in your opinion and why? Thanks in advance. west AF4GC best is any vertical from Force 12 - I got one on 75 meters that beats everything else I have put up. got one on 40 meters from Force 12 - beats everything else I have put up. need I go on? |
#7
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Best HF Vertical
In article ,
Jet_Li wrote: best is any vertical from Force 12 - I got one on 75 meters that beats everything else I have put up. got one on 40 meters from Force 12 - beats everything else I have put up. I went to the Force 12 website and clicked on the "Flagpole antennas" link http://force12inc.com/F12-flagpole-ants-003.htm. I read the "New 40 Meter Coil" portion of the page with interest -- sounded too good to be true. A moment's use of the calculator showed that the VSWR figures and the quoted feed point impedances were very inconsistent -- orders of magnitude wrong. The claimed SWR of 16 for the unloaded antenna worked out really to be about 850 -- close enough to infinity for me! If that's what the "useful A.R.R.L. TLW software" actually indicates, then the League should withdraw the software. But somehow I suspect that the software (which I do not have) doesn't predict what the web page says it does. I leave it to someone with a copy of EZNEC to see if an 1/8 wave monople on 40 metres made out of 2 inch diameter tubing really has an input impedance of about 5 - j460. That part, at least, sounds reasonable to me David, ex-W8EZE, who hasn't forgotten the formulas for SWR -- David Ryeburn To send e-mail, use "ca" instead of "caz". |
#8
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Best HF Vertical
David Ryeburn wrote in
: In article , Jet_Li wrote: best is any vertical from Force 12 - I got one on 75 meters that beats everything else I have put up. got one on 40 meters from Force 12 - beats everything else I have put up. I went to the Force 12 website and clicked on the "Flagpole antennas" link http://force12inc.com/F12-flagpole-ants-003.htm. I read the "New 40 Meter Coil" portion of the page with interest -- sounded too good to be true. A moment's use of the calculator showed that the VSWR figures and the quoted feed point impedances were very inconsistent -- orders of magnitude wrong. The claimed SWR of 16 for the unloaded antenna worked out really to be about 850 -- close enough to infinity for me! Your calc is about right (assuming Zo=50+j0). If that's what the "useful A.R.R.L. TLW software" actually indicates, then the League should withdraw the software. But somehow I suspect that the software (which I do not have) doesn't predict what the web page says it does. TLW suffers from some of the same issues as tables in the ARRL handbooks, but I haven't run Force12's numbers on TLW, I will use my own calculator. I leave it to someone with a copy of EZNEC to see if an 1/8 wave monople on 40 metres made out of 2 inch diameter tubing really has an input impedance of about 5 - j460. That part, at least, sounds reasonable to me David, I ran an analysis of a 10m "flagpole" as a multiband antenna, and the feedpoint impedance is around the 5-j460 if you ignore resistive loss in the ground system. Force12 might not want to include such in the analysis as it drives much lower efficiency. If they did achieve a coil of 10uH with Q=600, the additional R is ~0.7 ohms (about 0.6dB loss in the stated scenario), so their new 6-j22 looks a reasonable development(apart from the fact it also ignores ground resistance), and I make the VSWR(50) to be 10 rather than their stated 6. At the end of the day, the VSWR is not of itself the issue, the issue is what is the line loss and load impedance presented to the ATU, then the expected tuner loss. Their estimate of 2dB line loss for 100' is probably realistic, I make the loss on 100' of RG213 at 7MHz with load 6-j22 to be 2dB ( try it yourself at http://www.vk1od.net/tl/tllc.php ), and the load seen by the ATU is a manageable 8+j3.0. The Z into the line is highly dependent on the line length, but since Force12 give it, lets look at likely tuner efficiency. Using W9CF's tuner applet with default configuration, ATU loss might be around 0.7dB. This whole scenario predicts an antenna that might be quite acceptable to people with space or covenant issues, 3.3dB of total loss. But... What if ground resistance was 10 ohms, efficiency of the antenna and loading coil would be 5/(10+5+0.7) or 32% (5dB loss). That will help the line loss though, now with a feed Z of 15.7-j22, loss in the same line is 1dB and input Z is 16+j2. ATU loss might be more like 0.4dB. Total loss is 5+1+0.4 or 6.4dB. Although there analysis ignores ground resistance, possibly so as to hide the efficiency of the loaded radiator, the real situation might only be 3dB worse than they intimate. Of course, if the coil wasn't as good as they state, the picture is a little poorer. Similarly, achieving a low ground resistance isn't easy and the story could be much worse. Do they have credibility? Perhaps they should have stuck to the QSL card count method as the quantitative support for the design! The idea of a flagpole sings when an automatic ATU is placed at its base, but that doesn't solve the efficiency issue that exists with any Marconi with low radiation resistance. I wrote an article exploring an unloaded vertical as a multiband antenna, it is at http://www.vk1od.net/multibandunload...ical/index.htm and may be of interest. Owen |
#9
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Best HF Vertical
David Ryeburn wrote in
: In article , Jet_Li wrote: best is any vertical from Force 12 - I got one on 75 meters that beats everything else I have put up. got one on 40 meters from Force 12 - beats everything else I have put up. I went to the Force 12 website and clicked on the "Flagpole antennas" link http://force12inc.com/F12-flagpole-ants-003.htm. I read the "New 40 Meter Coil" portion of the page with interest -- sounded too good to be true. A moment's use of the calculator showed that the VSWR figures and the quoted feed point impedances were very inconsistent -- orders of magnitude wrong. The claimed SWR of 16 for the unloaded antenna worked out really to be about 850 -- close enough to infinity for me! Ah, but you calculated the VSWR at the load end. They calculated the much lower VSWR at the source end of the line. If you were Force12, you probably wouldn't want to publicise the extreme VSWR that users of the standard flagpole experience in this scenario. Owen |
#10
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Best HF Vertical
On Thu, 15 Mar 2007 00:08:30 +0000, west wrote:
I know I can go to eham.com but I like the advice on rraa better. I also know that this question is somewhat subjective, but if you will, please indulge. :-) What is flat out the best vertical HF antenna in your opinion and why? Thanks in advance. west AF4GC SteppIR. Why use a tuner to match your radio to your antenna, when you can make your antenna match your radio? --Teh |
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