antenna choice

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iv narrowed it down to 3 antennas for my qth with limited space,first choice is gap titan vertical,second is mfj 1775,and thirdly is the comet h-422,would like some comments on the best to get for my qth,running the flex 6500 with a pr40 microphone.thanks
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Tony Hateley

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Posted 4 years ago

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Tony Hateley

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because im in the uk,and our local concile look down on any antenna system with distain,you have to have planning permission from the said concile which you have to pay for it and is a very lengthy process,plus the fact that im a disabled pensioner does not help,no disrespect to you in the usa but you a spoilt when compared to the uk.thanks tony
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Steve K9ZW, Elmer

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Dealing with UK authorities to rebuild a long derelict cottage in the Lake District was borderline insane.  I know that the individuals I dealt with were fine people, but they would have never themselves accepted the limitations they tried to impose on folk like myself. 

Took a bit of doing, but eventually I used their incremental edicts to nudge them to allow what I wanted all along.  Involved too much stress, risk of arbitrariness leading to failure at any stage, and the risk of "finding things" made this success hollow - it just took much to do.  Oh and on "finding things" a friend's construction crew digging to repurpose an old cellar into a wine cellar found a 4-600 year old human skeleton... talk about finding trouble!  Cost him dearly too between the project interruption and the private mass & internment he felt compelled to provide this centuries old hunchback.

Stateside we're not always free of these same sorts of games - you can read all about my permitting fun & games when I put up my tower on my blog, but usually most of us do have more options for antennas both in available area and more relaxed code enforcement. 

Tony without some details on your QTH it is hard to suggest a solution, but perhaps it is worth consulting with some of your area hams to find out what solutions gave them the best performance? 

73

Steve

K9ZW


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Walt - KZ1F

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As I had said earlier, I did have a Gap Titan. They are not the least bit stealthy. You also really need to guy them so they actually take more real estate than you'd suspect. I suspect that is true regardless of the vertical. The Titan would need to be in the center with 14' or so of space at 4 corners.
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Ken - NM9P, Elmer

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I usually agree with Howard on most points.  In this case also, with the exception that a vertical can outperform a low dipole on 80/40/30 and a good inverted 'L' will way outperform most dipoles on 160 Meters unless the dipole is VERY high.  On 20 and above, most hams can get a dipole up high enough that it will outperform a vertical in MANY directions.

In my case, until I get my tower and 11 element Log Periodic in the air, I am using a 160 meter offset fed dipole at 38 ft.  It works well on most bands, (a good 4:1 or 6:1 current balun is necessary) and it has gain on higher frequencies at certain directions.  

However, my homebrew 34 ft. elevated vertical with 4 radial sets (like fan dipoles tuned to multiple bands) at 8 ft above ground often shows 6-12 dB gain over the dipole for DX out past about 3-4,000 miles on 40, 30 & 20 meters, and in many cases outperforms the dipole on 15-10 at selected distances and directions.  It is almost always better on 40 meters for most DX, but the dipole beats it in most of the US.

Yet, in 2013 I won the CQWPX 9th Region Unassisted QRP All Bands with a flex 1500 at 5 watts and a simple doublet 85 ft on a leg fed with 450 ohm line and a good tuner.  (It was also 4th in 9th Region in low power unassisted TB/Wires category)  So a simple wire antenna can be very effective.

In any case, if you have no option other than a vertical, make sure you have either elevated radials, or a good ground radial system under it.  DO NOT be fooled by those who say "I have a trap vertical and it loads up fine with no radials at all."  So will a dummy load!  Will a vertical WORK with no ground system?...yes.  Will it work WELL?  NO!  Especially not for DX.  Your take off angle and efficiency are both dependent upon the quality of the ground.  One note.... As you add your ground radials, you SWR may actually go UP because it lowers the impedance of the vertical and you will need to match it better.  But efficiency and power transfer are key... NOT SWR.  Matching networks can adjust for swr, but they cannot add RF efficiency that only proper antenna design can do.

But then... If I had permission, and unlimited funds, I would love a tower and antenna like Howard has!  And I would STILL drop an inverted 'L' from it for 160 and 80 Meters!

Good luck.  Ken - NM9P
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Ernest - W4EG

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Ken,
Your statement  "I have a trap vertical and it loads up fine with no radials at all." So will a dummy load! Especially not for DX.
I just have to tell you that in my case the 18-HT vertical has given me the opportunity to work DXCC + with NO radials:At an elevation of approx 1000 feet and agricultural soil. I operate 160-6 meters running 100W out of my 6700 and I am relocating to NE Florida and I am taking my vertical 
Is it the vertical or the operator that makes the difference and not theory?
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Ken - NM9P, Elmer

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I never said it wouldn't work AT ALL.  The 18-HighTower is a great, classic multi-band antenna.  But just think how much more effective it would be with a decent radial system...as the manufacturer recommends.  Your efficiency will go UP and your radiation angle will go DOWN, which is even better for DX.
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Jim Gilliam

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Has anyone modeled a vertical dipole with the bottom tip a few inches above earth? It would seem with the proximity of the lower leg of the dipole next to earth would relegate the antenna to not much more than a 1/4 wave vertical with one vertical radial.


Jim

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KY6LA - Howard, Elmer

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Ernest and Ken

Debates about Antennas are starting to sound more strident and opinionated than the debates about Religion, Sex, Politics, Legacy Radios and SDR's...

As I said, Verticals USUALLY tend to work poorly in all directions.  Traps, Resistors and Gimmicks instead of radials USUALLY tend to have very poor radiation efficiency.so that they can fool the radio into thinking that the SWR is 1:1

However... with lots of Radials, Verticals can perform OK as the radials tend to improve radiation efficiency...Verticals tend to have low angles of radiation so they CAN SOMETIMES work well for DX.

I have used a couple of phased verticals over salt water on a small DXpedition to Bora Bora in 2001.... They were amazing...beat the other guys on the team with their small Force 12 beam....

Tried to do the same thing with a single vertical over salt water on my DXpedition to Da Nang Viet Nam in 2012.. it worked terribly ... could not make any Q's beyond Indonesia and Thailand
Did better and worked the same guys remoting from my Flex 5000 in San Diego at the same time...

As Ernest knows, Dennis N6KI and I  as well as the other boys in the San Diego Contest Club have over the years bought or borrowed and tested virtually every antenna, and radio on the market to see if we can find any edge for contesting.  I think many of you read our humorous debate about the K3 vs 6700.  i have at least one first in North America and 2nd in the world contest result to my name so we must be doing something right.. albeit my location helps (600' ASL on the Pacific Coast) win Japan / Asia Pacific Contests...


Tony

A lot of what you choose for an antenna depends on local conditions including Politics, the soil you are on, the terrain and even your latitude. and climate

For example,even though I am 600' up from the ocean, I get a lot of salt water spray from the ocean.. which rusts any steel...so a Fiberglass SteppIR looked ideal.. except i have 320 days a year of sun .. so I had to marine paint the Fiberglass to prevent UV damage....


So I suggest you ask local hams in your area what seems to work well locally and what you can get away with Politically

.. you may be surprised to see what they say...
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Walt - KZ1F

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Cool, can we talk about sex and politics now?
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Richard McClelland, AA5S

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A vertical HF loop may still meet your vertical antenna constraint.  Here is a good  presentation regarding these: http://www.kn9b.us/loop-antenna plus there are many more articles to be found via Google.  If you use appropriately small diameter wire, these antennas can get by many HOAs.  My HOA covenants prohibit exterior antennas but my horizontal loop has been up for three years without any complaints.
(Edited)
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Richard McClelland, AA5S

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(Smoozing the neighbors does wonders when concealing antennas.)
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Terry K8EET

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Yeah, I put my loop up when no one was around and then asked my neighbors if they noticed anything different in the back yard. They couldn't see it until I showed them where it was. Then I invited them in to look at the signals bouncing up and down on my big screen. They were more impressed with CW then SSB.
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Richard McClelland, AA5S

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One of my neighbors is a professor of psychology.  He told me that he watched me for two hours as I put up my loop and was genuinely concerned for my well being.  I told him I am a ham operator and he realized in a flash that I wasn't performing some type of ritual incantations at dawn one Sunday morning.  He was very much relieved.
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Jim Gilliam

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If I were a professor of psychology, I would be more worried that you were a ham radio operator!
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Ken - NM9P, Elmer

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Howard...No real argument here.  There is a lot of junk sold as "Multiband verticals" whose only real selling point is "broadbanded" including some that are simple throwbacks to the old Van Gordon antenna with a better matching network. Some with a simple resistor network to give a constant 50 ohm match to the rig.  But the radiation efficiency is horrible!  But people swear by them because they make contacts.  But they may be using a compromise antenna with 100 watts that is getting performance comparable to a 5 watt rig and a decent antenna.  you can still make DX contacts if you work hard enough.

My emphasis was on the lower frequencies -- 160/80 and sometimes 40/30 where for longer DX a good efficient vertical with excellent ground, (not a junk trap vertical), usually has a lower effective angle of radiation that a dipole at the heights that MOST hams in my area are able to achieve easily.  (Those blessed with 100 ft trees can go ahead with the dipoles, loops, V-beams, rhombics, and wire yagi's!)

Yes, a rotatable dipole or 2 element beam at 85 ft or more will probably outperform the vertical on 40 meters.  But for DX work, I have a hard time believing that most hams can get a dipole up high enough on 80/160 to be better for DX than a well designed vertical or inverted 'L'.  Though I have heard some monster stations with rotatable 3 element full sized yagis on 80 meters.... (crazy loud signal and lots of $$$!) 

But, If I could swing a tower and antenna like yours,  I wouldn't mess with verticals on 40 and above at all!  When I get the T-11 Log Periodic up at 58 ft, my vertical will be redesigned for 40/30 exclusively.  I won't need it on the higher bands any more.  But I will need BOTH my dipoles and vertical/ inverted 'L' for 160-40 depending upon the distance.
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KY6LA - Howard, Elmer

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Ken

Great minds think alike...

As I keep on repeating myself.. over the years when I was traveling a lot for business all over the world, I bought and played with most of those gimmick - traps - resistors - tuning thingy- verticals ..  why?  I kept on dreaming that there was a magic bullet that would play well for me....


. with very rare exceptions (the SteppIR BIgIR was one exception) none of them played very well EXCEPT when we phased a couple of verticals over salt water in Bora Bora......

Even when I was the rare DX and people really wanted to work me the Inverted V's in a tree invariably got better responses than the gimmick verticals...  So much for low angles of radiation...  Radiation Efficiency beats low angles most of the time....

Further our contest club (especially Dennis N6KI and Myself) borrows or buys and plays with virtually every antenna we can find in a never ending process to find an extra edge in contesting....

The superb reports you see around the Internet are usually from Hams who have never had a beam to compare with their gimmick vertical... a very close friend and neighbor of mine living in an HOA absolutely swears by his gimmick vertical (basically a large resistor)...yet when I call him to alert him to some DX booming into my station, 90% of the time he can barely hear them....

So I have a hard time recommending any of the compromise vertical antennas as they as usually a waste of money...



If one is to put up a vertical then avoid the gimmicks - put up a full quarter wave with a full ground system... over better yet.. elevate the vertical with a good ground plane...

I rarely work 160M.. only have a shortened dipole   but I have a rotatable dipole for 80/60M at 85', 3 elements on 40M, 4 Elements 20,17,15,12, 10 and 6 Elements on 6M...   Interestingly enough I actually get better performance on the highest bands by lowering the tower to improve the angle of radiation....
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James Skupien

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Check out a Zero5 vertical if your looking vertical, I have 2 of them and work very well! If you have room for a wire, Look at a Off Center Fed Dipole! works great with a Flex to look over multiple bands.

73!

Jim AA9NN

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Rich McCabe

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I  agree with James. I am not going to debate this as I am not qualified to do so with some of the hams posting in this thread.  I do not have that level of expertise. However a Zero Five with  lots of buried radials AND a remote antenna tuner which is much less loss than running the UN-UN option is a decent antenna.

I am surprised that distance of communication has not been discussed. Not only is there a difference in gain but angle of radiation differences are significant. So the difference between horizontal and vertical is not the same for me at 300 miles vs 3000 miles.
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Walt - KZ1F

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I believe we have successfully hijacked this thread. We should all be better about the squatting thing. The original question was, "I've narrowed down my choices to these three...which is best". Now people are just talking amongst themselves off topic of the original question. Personally, I hate when people hijack my threads, it's totally annoying. I suspect if Tony was into DXing or Contesting his three choices wouldn't be verticals. Tony, if limited to those three choices, I'd go with the Gap Titan and put it in the middle of a 6'x6' metal mesh at ground level per Gap engineer. He told me the difference would be astounding.

Walt - kz1f
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KT0AM - Mark

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Hear, Hear!! And in the meantime, I'll keep using the big resistor to get DXCC! Happy New Year to all fellow Flexers.
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Burt Fisher

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When you are in a conversation at a party ( a real party not a QSO party) and the conversation moves away from the central beginning do you say to the group this CONVERSATION has been hijacked?
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KY6LA - Howard, Elmer

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Yet another gimmick vertical antenna. Good SWR terrible radiation efficiency.
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Jim Gilliam

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Just look at the good side...less probable TVI
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Jim Gilliam

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Did anyone ask the engineer why this "magic mesh" isn't included as part of the antenna kit?
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Walt - KZ1F

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Jim, He and I actually talked about it. The Gap Titan does not need radials as it has the counterpoise that, in theory, negates the need for them, it also helps with 40mtrs. But he said the mesh augmented the counterpoise to give the signal a lower angle of radiation. I did not try that as I didn't want a 36 square foot brown patch in the middle of our backyard. I provide that information only as advice from a Gap engineer. He, btw, swore by it. That was in the summer of 2002, so I am sketchy on the specifics. Personally I am not a fan of verticals but given Tony limited his choices to one of those 3 verticals, I commented on what I knew about the Gap Titan. I also know several other hams that love theirs. FWIW.

Walt
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Jim Gilliam

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I am not an antenna engineer, but my gut tells me that a vertical dipole with the lower element at ground level, is more a vertical with one vertical radial. I am going to pursue this idea further. It would seem since the lower element is not a "free radiator", that there has to be some inefficiency compared to a horizontal dipole at a reasonable height. There is just too much poor information given by manufacturers to get you to buy their wares.



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Walt - KZ1F

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There is a gap, ergo the company name, that separates the 2 primary radiators. When you order you specify which segment of 80mtrs you want to be on as they supply the capacitor that helps tune the 80 mtr segment (phone/CW). Radiators for the higher bands are electrically isolated from the main radiator as side appendages, for lack of a better term. I believe, if for no other reason than, being called a vertical dipole there is likely some gain radiation shaping. I refer all interested to here http://www.njqrp.org/data/gap.html

Walt - kz1f
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Walt - KZ1F

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Hey Tony, if you want to talk Gap Titan, email me direct via qrz email.
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Charles - K5UA

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Several comments on verticals:

1. Efficiency of a vertical is proportional to radiation resistance of the vertical radiator divided by the radiation resistance plus the ground resistance. Over an infinite copper plate the ground resistance would be zero, and the efficiency would be 100%. Even with 120 radials there would be a few ohms of ground resistance, but the effeciency would be very high with a quarter-wave radiator of about 37 ohms radiation resistance. I.e., 37 ohms divided by 37 ohms + 3 ohms = about 92% efficiency. Not only is such a vertical efficient, the maximum take off angle is virtually zero degrees with very little high angle radiation..

2. At low take-off angles necessary for DXing, a dipole for 80 meters would have to be 220 high to compete with an elevated vertical 10 feet high with two elevated radials 10 feet high. Don't believe it? Model it in EZNec and see for your self. How about the 80 meter dipole at 66 feet ( a scenario more likely for the average ham ). The elevated vertical at low angles way outperforms the dipole. If you want to ragchew with your local buddies on 80 meters, use the cloud warming dipole at 66 feet.

3. The base loaded verticals that are significantly less than a quarter-wave long have only a few ohms of radiation resistance. They can be efficient with a very good radial system. With a poor radial system the efficiency will be very low , and the take-off angle will be much higher, with less gain.

4. It's all a matter of wavelength. On 20 meters and above, one can get a horizontally polarized dipole or yagi a wavelength off the ground for a modest investment. Below 20 metres (70 feet), towers get pretty expensive and antennas get pretty big. The vertical, especially the elevated vertical, is a lot of DX bang for the buck.