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[Articles Home]  [Add Article]  

Top 5 Get-On-the-Air-Quickly Antennas

Don Keith (N4KC) on March 24, 2009
View comments about this article!

N4KC's TOP FIVE GET-ON-THE-AIR-QUICKLY ANTENNAS

By Don Keith N4KC

Some of us give up too easily. Or we are too timid to give something new a try. I have seen several examples of this lately. One was a new amateur who got all excited after he upgraded, acquired a perfectly adequate HF station, but then so far has not gotten around to erecting any kind of decent antenna to use with it. I don't know if is because he is intimidated due to lack of knowledge about antennas or if he simply is not sure what type of antenna to put up. Maybe he hesitated, thinking he should wait until he had the perfect choice, or something that would elicit “ooohs” and “aaahs” from stations he worked. Think back a hundred years ago when you first got your ticket. All this stuff was a lot to take in at the beginning.

I also know of a long-time ham who came back from a period of inactivity, dragged the old gear out of the closet, and then, for whatever reason, never quite got around to the most important part of the station—the antenna! He threw some wire out the window but could hardly hear anything, and his radio just hissed at him when he tried to tune up that mess.

I confess I am a procrastinator. I tend to spend a long time getting ready to start to begin to commence to think about launching a project until I inevitably forget what it was I wanted to do. And, by the way, what did I buy those parts and rope and wire and fiberglass and aluminum for in the first place?

But this is different. People who may be otherwise enthusiastic about starting or resuming the hobby are allowing fear or hesitancy to keep them on the sidelines. I'm afraid that some of us who attempt to Elmer them sometimes contribute to the problem by pushing antenna ideas that are beyond their means, knowledge or geography. Or even sometimes beyond their interest level or desire for learning. Not everyone wants to be an RF engineer. They just want to work some DX or conjure up a ragchew. There is nothing wrong with that!

In that spirit, I'd like to list below what I would recommend as the five best get-on-the-air-quickly-and-easily antenna ideas. Maybe you have other suggestions, but understand that I am applying the following logic in picking these particular ones:

  • They are easy to build for most anyone who is willing to try and do not require any special tools or test equipment.

  • They may be crafted from easily available materials and cost very little, so there is not much downside if you mess them up.

  • They are not necessarily the be-all, end-all of RF radiators but they do work well enough to give a good experience to the user.

  • They are not necessarily the best for all situations, including for use in antenna-restricted neighborhoods or in condos and apartments. That's another article.

  • And if someone attempts to construct one of these bad boys, he or she will possibly learn a little antenna theory by osmosis and, just maybe, will become curious enough about the subject to learn more and try more challenging projects.

Now, in no particular order of preference, here are N4KC's Top Five Get-on-the-Air-Quickly Antennas:

#1 - The half-wave wire dipole

It is about as basic as it gets and it can work quite well on any HF band. It consists of two pieces of conductive wire stretched end-to-end, and joined together in the middle with a short insulator. We call that the feed point. Insulators and lengths of rope are attached to each of the opposite ends to support the antenna. Some call this a “flat top” antenna or a “doublet.”

0x01 graphic

It can be hung between two supports—often trees—parallel to the ground. It can also be supported in the middle with the ends sloping downward in an inverted “vee” configuration. For some reason, this is often called an “inverted vee” antenna. If you remember geometry, it might be obvious to you that the inverted vee takes less space than the flat top.

This antenna can be fed with coax, such as the popular and relatively inexpensive RG-8X, which is easy to run from the middle of the dipole to your shack. The center conductor of the coax is soldered or clamped to one leg of the dipole and the shield is attached to the other. There are several commercially available center insulators that allow you to simply screw your coax onto the insulator.

Copper wire is usually used for a number of reasons. The gauge of the wire is not that important so long as it is big enough to adequately support the antenna but not so big that it becomes too heavy and droops. The support ropes should be weather and UV resistant unless you enjoy reattaching them often and tossing them back over the limb.

As with most antennas, the higher in the air you can get a dipole, the better, if you want to work distant stations. You will make contacts, though, if it is just above head high, and in some cases it actually works better over closer range than if it was in the clouds.

The overall length is determined by the formula 468/frequency in megahertz. Results are in feet. That means a dipole cut for 3.8 megahertz will be about 123 feet long, or each leg will be about 61 feet 6 inches. You would need supports (trees) about 130 feet apart with no obstacles between, although you can bend the legs around stuff if you really need to.

PROS: Cheap, easy to put up, works well on the band for which it is cut, and if it falls down, just put it back up. If it breaks, splice it and put it back up. You can bend the legs to fit on your lot, too. It is also relatively stealthy since it is difficult to see among trees. You could probably fit one for 30 meters or higher in an attic or beneath an eave on the house.

CONS: Needs to be high in the air for DX, is directional to some extent but with little or no gain on its fundamental frequency, and will only be close to resonant on odd multiple harmonics. That means your 3.8 megahertz antenna will probably only be useable on that band without a wide-range antenna tuner. A dipole cut for 7.1 megahertz would work okay on the high end of 15 meters but would be problematic on other bands. Coax feedline can have lots of loss in high SWR conditions, so even if your tuner makes it work, you may have noticeable loss of power.

#2 - The doublet with parallel feedline

0x01 graphic

Photo: W7FG

An effective radiator since the beginning of the hobby, this antenna is really just a dipole, as described above, but fed with open-wire feedline, ladder line, or window line—feedline in which the two conductors are kept the same distance apart from antenna to shack. Since the dipole is a “balanced” radiator and parallel feedline is a pair of parallel conductors, they really like each other. (See my window-line doublet article at my web site, www.n4kc.com)

0x01 graphic

PROS: In addition to the pros above, this antenna also works well on most bands above the one for which you cut it. Since the parallel feedline typically has very little loss even when the SWR is high, the antenna becomes a good multi-band antenna when fed with this type line and used with a wide-range antenna tuner. A balanced tuner is even better.

CONS: Open wire feedline must be kept at least a few inches away from metal or other conductors, including the ground. That makes it problematic running the stuff into some shacks alongside coax or near gutters. Since most modern radios have 50-ohm unbalanced outputs, you will need a balun to make the transition from balanced antenna and feedline to unbalanced radio. (Read up on baluns. They can make life easier or more difficult, depending on whether or not you understand them and how they work.) The length of your feedline is also a factor in how the antenna tunes and you may need to experiment to get the correct length for best results on the most bands.

#3 - The quarter-wavelength vertical

A vertical radiator has several advantages over horizontal antennas, including being omni-directional, having a low-angle of radiation (trust me, this is a good thing for DX), and taking minimal space. And it can be as simple as hanging a piece of zip cord from a tree limb.

Of course, the wire needs to be insulated from the tree and run some distance away from any other metallic object like an aluminum mast, tower, or supporting structure. The formula for the antenna's length is 234/frequency in megahertz. That's right. Half as much as the half-wave dipole above. For 40 meters, the vertical radiating element (wire, aluminum, a flag pole…anything you can hook one side of coax to) is about 33 feet.

Got a tree limb 35 feet off the ground? Tie a knot in a 33-foot-long piece of copper wire, run a rope through the knot, and throw the rope over the limb, tying it off to the trunk. Pull the wire up until the lower end of the wire is three to six inches from the ground. Now lay out pre-cut pieces of wire that are approximately 33 feet long, stretching each one outward from where the bottom of the vertical wire hangs, arraying them in a radial pattern. (See they article about my vertical experiences at www.n4kc.com)

0x01 graphic

Use 20 or 30 wires, which we will call “radials.” Are 20 or 30 enough? Can you get by with 4 or 8? Yes and yes. But getting at least 20 is a good thing and then you begin to get diminishing returns. Getting more short radials is also better than fewer long ones. Tie the radials together where they all come together in the middle, beneath the vertical. Now solder the shield side of some RG-8X to where the radials are twisted together. Solder the center conductor of the coax to the bottom of the hanging wire. Weatherproof it as best you can.

Trench out a shallow ditch and bury the coax (make sure that is approved for burial beneath the ground) to a point where you can run it into your shack. Note: you may need to put a balun or some toroids on the feedline to keep RF from traveling along the shield. Sometimes the feedline looks like another radial and can pick up stray RF and conduct it into the shack. Once there, it can cause cussing and angst.

There are several commercially made verticals that offer more strength and, through the use of traps or other technology, make them multi-banded. I use a Hustler 4BTV and it is a good antenna. I bought it used for $50. But note that you still need a radial field under any quarter-wavelength-long vertical antenna that is ground-mounted, no matter what the sales pitch says.

Yes, a vertical can be mounted above ground, usually on a mast, and this has its benefits as well. You still need at least two radials for each band you will operate on, cut to be a quarter wavelength for each band. You may even need to do some tuning on those radials, cutting or lengthening them to get the lowest SWR. (But do not worry about 1.5- or 1.7-to-1 and spend hours of perfectly good operating time trying to get it flat!)

If you have a multi-band vertical mounted above the ground, there should be a set of radials for each band that you use (a 40-meter radial will suffice for 15). Getting the antenna up and tying off those radials can be a chore, though.

PROS: A simple and effective antenna, it is omni-directional. Since it is vertical, it takes very little space to erect. Many hams raise them when they want to operate and lower them when not on the air. The angle of radiation is most conducive to working longer distances. Commercially made verticals are available and are quite inexpensive.

CONS: It is omni-directional, so you reel in signals from and cast out RF into all directions, not just the one in which the station you want to work happens to be. It is also more susceptible to manmade noise than a horizontal antenna. It requires a radial field…the more wire the better…so you may not have enough real estate to stretch out radials in all directions that are equal to the height of the vertical radiator. That can be quite a bit of wire! The feedline also needs to be buried, and it can pick up stray RF and ferry it right into your house.

#4 - The horizontal loop

One of my personal favorites, the horizontal loop can be a good performer, stealthy, and will fit on many smaller lots that a full-size, half-wavelength dipole won't. (See the loop article on my web site at www.n4kc.com) A loop is just what it sounds like: a big loop of wire, supported by anything you can find to hold it up it as it makes its way around the backyard or the entire lot. Many hams tack the wire beneath the eaves of their house all the way around. Others erect poles or masts at four corners and make a square loop.

0x01 graphic

When you bring the ends of the wire together at the feed point, you use a short insulator to tie them together, leaving a gap. One conductor of the feedline is attached to one end, the other side to the other end. You can feed with coax or open wire feedline, but open wire is a much better choice if you want to use the antenna on bands where it is not resonant. Good news: the loop will be resonant on all harmonic frequencies, not just the odd ones. That means a loop cut for 7.1 megahertz will be close to resonant on 14.2, 21.3, and 28.4 megahertz.

For a resonant loop, the wire length should be calculated using the formula 1005/frequency in megahertz. A loop cut for 3.8 megahertz is about 264 feet long. A perfect loop is arrayed in a circle, but a square, diamond or rectangle shape is fine, so long as the rectangle is not too “skinny.” If you plan to use the loop on multiple bands, simply make sure it is cut at least as long as needed for the lowest frequency on which you intend to operate.

Like the dipoles, a loop performs for DX better if it is higher in the air.

0x01 graphic

PROS: One of the quieter choices for an antenna, it ignores much manmade noise. It can often fit on real estate that a dipole will not, especially considering its shape does not necessarily have to be round. It can be supported by whatever trees or other structures you happen to have. You do not have to rely on trees or other supports being strategically placed on your lot. And if you use insulated wire, you can run it through trees and bushes with little effect. It also has useable gain, especially above the fundamental frequency, with lobes that increase in number as you go higher in frequency. Use open wire or ladder line to feed the loop, employ a wide-range antenna tuner, and it becomes a wonderful multi-band antenna.

CONS: That much wire can be heavy, causing it to droop. It also requires maintenance since lots of things can happen to a stretch of wire that long (a 160 meter full-wavelength loop is almost 560 feet long!). It can certainly snag lightning, too, and blowing dust, rain or snow can create a lethal voltage static charge at the end of your feedline. Make sure it is grounded—outside—in such weather. With those gain lobes mentioned above, you also get nulls. If the station you want to work is in the middle of a nice lobe, super! If he is in one of those deep nulls, “Sorry, old man, you're down in the mud!”

#5 - The G5RV

The most discussed, maligned and misunderstood of all the simple antennas! Introduced by a British ham with the call sign G5RV, it has gotten a bad rap because so many manufacturers claim it to be an all-band antenna, “using only your rig's internal tuner!” Well, no.

0x01 graphic

By generally accepted definition today, the G5RV is a 102-foot-long dipole, fed with a matching section of 450-ohm window line, and then it uses coax the rest of the way to the shack. My authority on this is none other than the ARRL's Antenna Book. Take it up with them if you disagree.

In my experience, the G5RV will work fine on 40 and 20 meters, is not bad on 17 or 10, and might work okay on a narrow portion of 80/75. I can tune it with a good tuner on other bands but it is mediocre at best and the internal tuner in my rig merely fusses and refuses to even try on those bands. (In all fairness, my G5RV is a derivative version that is 6 feet shorter than the classic version.)

Google “G5RV” for several construction articles. There are also G5RVs available that are commercially made but I cannot vouch for any of them. I would be leery of any that claim “all bands with your rig's internal tuner!”

To get on the air the same day I bought my transceiver several years ago, I purchased a kit from The Wireman for less than the wire, ladder line and insulators would have cost. It has been up ever since and is sometimes my best antenna on 40. And unlike some recommend, I do not use a balun at the crossover point from window line to coax.

PROS: Makes a good antenna on several ham bands, yet it is shorter than a dipole for 80/75. On 20, it produces four gain lobes in a cloverleaf pattern, which gives you a very good signal in those four directions. It is cheap and, if you follow measuring instructions precisely, it is easy to build and hang. It can be used in an inverted vee configuration, too, if you lack the room or end supports.

CONS: It is not an all-band antenna, any more than any length of random wire and feedline is an all-band antenna. You could create some problematic mismatches, even for a good tuner, if you do not follow recommended measurements closely. The window line should hang down vertically as far as possible so you need to be able to get the feed point up at least 45 feet or so. And since a portion of the feedline is coax, it will be lossy if you have a high SWR. Keep the coax as short as possible.

So there they are. As mentioned, the main reason for this exercise is to give the new ham or someone who is returning to the hobby a bit of inspiration and some choices to consider for an antenna. And to urge them not to be too ambitious—ambitious to the point they never get around to putting anything up!

I think many of you will find a great deal of satisfaction in building your own aerial and then seeing how it works. There is certainly more satisfaction in that for many of us than there is in buying something already built and simply draping it over something in the backyard.

I do encourage you to play with your design. Try things. If they help, keep them. If they make your antenna a dummy load, toss it and start over. But most of all, have fun. And tell us about your experiences.

We are always interested in learning more.

Information sources on the Internet for these basic antennas:

L.B. Cebik, W4RNL's wonderful web site: www.cebik.com

Wikipedia (good article for beginner): http://en.wikipedia.org/wiki/Dipole_antenna

QST, June 1991 article on dipole: http://www.arrl.org/tis/info/pdf/9106023.pdf

Athens Amateur Radio club article by KV5R: http://athensarc.org/ladder.asp

N4KC's eHam article on ladderline doublets: http://www.eham.net/articles/16690

W8JI's excellent article on choosing the correct balun for the application:

Butternut article on verticals: http://www.bencher.com/pdfs/00361ZZV.pdf

Another Butternut vertical article: http://www.bencher.com/pdfs/00815ZZV.pdf

N4KC's horizontal loop article: http://www.donkeith.com/n4kc/skywire.htm

Loop dimension calculator and article: http://ka1fsb.home.att.net/loopcalc.html

IW5EDI article on G5RV antenna: http://www.iw5edi.com/ham-radio/?g5rv-antenna,66

Construction guide by G5RV himself: http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=9756

Short but informative G5RV article: http://diz.faithweb.com/builders/g5rv.htm

Very interesting G5RV article by VK1OD: http://vk1od.net/antenna/G5RV/optimising.htm

Member Comments:
This article has expired. No more comments may be added.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by WX7G on March 24, 2009 Mail this to a friend!
An excellent article that will surely help the new ham get on the air. Most hams want multiband antennas and the article covered it well. I am partial to the center fed zepp for a wire antenna and the 5BTV for a vertical.

And don't forget mobile antennas for CC&R neighborhoods. I use a ground mounted screwdriver for DXing on 80-10 meters and am quite satisfied with the results.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by K1CJS on March 24, 2009 Mail this to a friend!
Nice article! Thanks for compiling the information.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by KB2DHG on March 24, 2009 Mail this to a friend!
A very nice article for sure... Yes, antennas are alwasy a sore point or hurdle when it comes to getting started. Most of the problmens with antennas are home owner associations and restrictions. NOT what antenna to use. If I had my way, I would have a beam and several dipole antennas cut for each band. BUT I live in a condo.
I am using a home brew G5RV and contrary to your description on the cons of a G5RV, I work ALL bands excepty 160 meters with GREAT results. To me the G5RV is the #1 choice for a multi band single antenna.
Yes, for best results it must be erected no less than 35 feet and the ladder line verticle but it does work very well and can be tuned to work 80-10 meters. 40 and 20 work the best but I do operate 80,17 and 30 meters as well..
Thanks for the nice article.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by K8POS on March 24, 2009 Mail this to a friend!
Thank you,
Your article cut through a lot of QRM about antennas. No fancy feed patterns, SWR charts, or radiation charts. Just a plane simple this is about what you can expect.
I am in the process now of selecting an antenna to erect. Just so I could listen in I built a dipole cut for 20 meters, fed with RG59 (all I had laying around). It is 10 Feet in the air if I am lucky. I just wanted to listen to what was around before I purchased/made a more permanent antenna set up. In 3 days time I have worked 6 countries with it on 20 meters. Due to my yard layout, I am going to use a OCF dipole.

Bob
 
Top 5 Get-On-the-Air-Quickly Antennas  
by K9YNF on March 24, 2009 Mail this to a friend!
Very nice article, Don!

Reminds me of my first Novice antenna (a longwire) way back when in the '60s. And those 'helpful' Official Observer' reports telling me of all the harmonics I was causing. Yikes! If I had only met you then, Don!

Now, I have one of the best DXing arrays I ever built, a 20/17-meter widespaced 4-square. That dog really hunts!

You are such a wonderful writer, Don. How about putting out a book on this subject?

I'll be standing by for your next great piece.

73,

Wayne C. Long, K9YNF
Cascade, Wisconsin
 
Top 5 Get-On-the-Air-Quickly Antennas  
by N1KFC on March 24, 2009 Mail this to a friend!
Informative and well written article. This is the type of articles that would serve well in a separate eHam section for new hams. Thank you for sharing your knowledge and experience.



Perhaps eHam could change the text color for the links to something more readable than the yellow that was used.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by K0BG on March 24, 2009 Mail this to a friend!
The only thing I'd do different with respect to coax-fed dipoles, is to cut the length for the bottom of the band. Then, attach the end insulators about a foot or so from the end of the wires, and let the remainder "dangle". By folding back the dangles, the resonant point can be easily adjusted without splicing the wire.

If you think your OCF wire, 43 foot vertical, or j-pole will out perform what's presented here, you're wrong!

Alan, KBG
www.k0bg.com
 
Top 5 Get-On-the-Air-Quickly Antennas  
by N0AH on March 24, 2009 Mail this to a friend!
Come on......Hustler 4BTV will smoke these wire nut jobs-
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N0YXB on March 24, 2009 Mail this to a friend!
This is one of the best articles I've seen on eHam yet. Nice job!

Vince
N0YXB
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by G3LBS on March 24, 2009 Mail this to a friend!
Excellent article, particularly informative for new hams.
My G5RV, 51 ft each side, will load all bands 160 to 10, using a Johnson Matchbox true differential tuner.
I think the reason for varying reviews of it is that people don't realize that as you go higher in frequency, sharper lobes are produced and if you don't know where they are you will either be disappointed or elated!
Just being patriotic to my countryman G5RV I expect you'll say?
W2/G3LBS
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by K4RAF on March 24, 2009 Mail this to a friend!
Gotham Vertical S-T-R-A-P !!!
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KE7FD on March 24, 2009 Mail this to a friend!
Excellent article Don. I have used an 80m loop for many years now in Western PA. Despite the common assertion that loops will only provide "local" communications, I have been successful reaching Europe, South America and points west all with less than 100 watts. The success of the skyloop has been so high that a group of us installed a stealth loop along the flat roof line of a large building and feeding the loop with an SGC tuner. This arrangement allows us to transfer as much energy to the antenna regardless of the band being operated.

As a novice in the previous century, the venerable Dipole was standard fair. However, If I knew then what I know now, I would go straight to a loop if I had to do it all over again.

Again, great information, right to the point and worthy of printing off and kept as part of a grab and go kit too.

Glen - KE7FD
www.ke7fd.com
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KD4HSO on March 24, 2009 Mail this to a friend!
I'm surprised a simple end fed wire (with tuner) has not been mentioned. I run mine off the corner of my two story house, across the yard, back to the fence. It's probably about 100' long and has no problem matching even on 160m.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by K0BG on March 24, 2009 Mail this to a friend!
A couple of folks mentioned their antennas "match". That fact alone doesn't mean anything. You might as well refer to the number of DX stations you've worked.

Alan, KBG
www.k0bg.com
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by K4ZN on March 24, 2009 Mail this to a friend!
1. Great article
2. Yellow (or some such color) links are hard to read on my computer.
3. Re: BalUn for use with ladder/window line is not needed with a LINK COUPLED tuner. Link coupled tuners can be HOME BREWED.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB1QBZ on March 24, 2009 Mail this to a friend!
Pure heresy. Shocking. You should have your license revoked!!!

Imagine, suggesting that people should get on the air with something other than a perfect antenna capable of busting DX pileups.

Here, just look what some of the REAL experts have to say on the subject in another thread

http://www.eham.net/forums/Elmers/214917

Seriously, thank you for an excellent piece. You made it easier and simpler sounding than most articles make it sound. And now that I have the experience of putting up a couple of antennas, I think that your piece is very reasonable in its description of easy it is to put up some of these antennas.

However, had a read your piece 9 or 10 months ago, I would have chortled, said "yeah, right, sure", and gone looking for ads for some "easy to install" wonder antenna. A lot of us are blocked from putting up antennas like those you describe by our own perceived lack of ability to do "mechanical" things like putting up antennas.

In my case, for example, I just had no idea how to even begin putting a dipole 35 or 45 feet up into a tree, or how to get a rope tossed over a tree limb that's 35 feet high.

With the eventual help of someone from a local club (it took a while to find a local club and join it), I was introduced to Mr. EZ-Hang and other little tricks, and now have a Radioworks Carolina Windom 80 Special installed about 40 feet up (maybe 45 feet). But it took a while to get to that point and there was a lot of angst, agita, and wondering why I had decided to become a ham.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by AE6Y on March 24, 2009 Mail this to a friend!
Don, Thanks for a very sensible and clearly presented article. I would only add to the Dipole portion the suggestion that multiple bands are very easily supported with a "fan" or "parallel" dipole, by having several dipoles attached at a common feedpoint. I once had one for 40/20/10 with three wires separated a few inches by wooden spacers, and it was a cheap and easy way to get on the air (and, as you note, it also worked on 15).
73, Andy, AE6Y
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by W3TTT on March 24, 2009 Mail this to a friend!
Great article, my complements on a well written piece.
I would add the end-fed Zepp antenna to the list. It is one of the easiest to construct. Take a half wave length of wire, solder it to a quater wave of ladder line or 8/10ths of a quater wave of TV twin lead. Solder the twinlead to the antenna connector. That's all. The wire can go just about anywhere, vertical, horizontal, out your apartment window. No ground wires needed, no counterpoise needed. Just about the simplest antenna possible. I made some lightweight versions that I use for camping.
Don't forget about the vertical antenna with raised radicals. If the radicals are raised a few tenths of a wavelength above ground level, then you only need two or three radicals, not 20. This is my main antenna. I use an antenna tuner, even with coax. This is because the coax is only 8 feet long, from window to roof level.
Joe n3iqa
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N6AJR on March 24, 2009 Mail this to a friend!
blasphemy, not a word about the Fan Dipole.. shocking:)
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by WV4L on March 24, 2009 Mail this to a friend!
My compliments to you as well Don on this article. When choosing my first antenna I ended up referring to your site and choosing the Horizontal Loop antenna for my needs. My medium sized lot has some very large Oaks on it, so it worked out nicely for getting lines over limbs to pull the loop up into the air. Although cut for 40 meters, as described it works well when tuned for the other bands.

73!
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by WB9URN on March 24, 2009 Mail this to a friend!
I don't know if it was your idea, or my browser's, but the use of yellow for the links makes them unreadable. Especially for those of us with 68 year-old eyes.

Very good article, otherwise.
Thanks for writing.

Alllen
WB9URN
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by QRZDXR2 on March 24, 2009 Mail this to a friend!
More wire... longer wire... better antenna ??

The best antenna you could get is a loop. For the most effecent if one could use the loop antenna as part of the output tank LC network. I.e instead of a inductor /cap in the output .. use the loop antenna as the inductor and tune it with a cap directly for resonance. That would be the best antenna you could have.. most effecent. no coupling

Just one small minor problem .. you would be stuck on one frequency only unless you could find a way to change the lenght of the inductor/loop antenna.

In days of old a gent by the name of Armstrong (you may have heard of him) tried this and it seemed to have good results.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by K9ZF on March 24, 2009 Mail this to a friend!
Great job!

I hope your article will inspire some folks to try experimenting with antennas. This is one of the most enjoyable parts of ham radio for me:-)


73
Dan
--
Amateur Radio Emergency Service, Clark County Indiana. EM78el
K9ZF /R no budget Rover ***QRP-l #1269 Check out the Rover Resource Page at:
<http://www.qsl.net/n9rla> List Administrator for: InHam+grid-loc+ham-books
Ask me how to join the Indiana Ham Mailing list!

 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by W0FM on March 24, 2009 Mail this to a friend!
A quick visit to Don's website will reveal the basis for our appreciation of his writing skills. Impressive. Check it out:

http://www.donkeith.com/

Nice article, Don. Thanks.

Terry, WFM
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N4KC on March 24, 2009 Mail this to a friend!
Thanks for the feedback, and a couple of comments:

-- Not sure how those URLs turned yellow. They looked fine on the Word doc I uploaded to eHam.

-- Fan dipoles are fine, but may be a little cranky getting the interaction tuned out...trying to keep it as simple as possible.

-- Keep the suggestions coming...end-fed wire, fan dipole, OCF dipole...all good suggestions and will get folks thinking. Thinking and building. Building and talking.

Don N4KC
www.n4kc.com
www.donkeith.com
www.n4kc.blogspot.com
(An open blog dedicated to rapidly changing technology and its effect
on society, media and amateur radio)


 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by W4VR on March 24, 2009 Mail this to a friend!
Good article for novices, or anyone new to HF. The center-fed dipole with open wire feeders is probably the best all around antenna if you want to get something up in a hurry and operate all bands. The G5RV is not such a great antenna, unless it's fed with open-wire line period...perhaps an OCF antenna would have been a good substitute for the G5RV.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by NO6L on March 24, 2009 Mail this to a friend!
Very good article without a bunch of theory. Theory is nice, but it can derail an attempt by an HF newcomer to get an adequate antenna in the air. For example, theory says you need at least 64 radials for a vertical to work at it's best. But what is not mentioned enough is that even a few can get decent performance. Height is also over emphasized. DX is many times promoted and local NVIS mode is forsaken. This mode is one of the best for what Amateur Radio is all about, emergency communications. In a local disaster, repeaters may not be available to cross a mountain range. But with an 80M "V" only 20 to 30 feet high your signal will propagate almost straight up and down to the other side of a mountain.

Pros: Like I said, the article was decent it was informative and wasn't cluttered with distracting theory.

However...

Cons: It was incomplete. DX, was again stressed while the very important NVIS mode was not mentioned at all. True, it won't get you a WAS or DXCC award, but it can mean the difference between being heard well locally on low band HF, and not. It also is a very good way to foster a local group on HF that can meet in person from time to time. For what it's worth, mine is only 40' and on 80M I work the entire 11 western states, easy, and eastern stations with only a little more effort.

Another thing not mentioned was that you can use a "V" or flat top on different bands without a tuner, many times, if you deploy a multiband fan dipole or a maypole antenna. And, you won't need to babysit a run of open line feeder with careful routing, standoffs and tolerate potential feedline radiation to use it. Coaxial cable is just the ticket, and when you do need a tuner, the VSWR is low enough you won't have significant feedline losses. Yes, you will need a 1:1 balun. But, I'll take a balun over the headaches that come with open line feeder any day.

As for a G5RV, I don't even consider these "antennas" on 40 and 75. Every station using one I hear, without exception, running over a kilowatt sounds like they're doing 100 watts into a flat top or V. I'm sorry, but there it is, the ugly truth. It's a classic example of, "If the VSWR is good, you're getting out". They work great on 20M, the band they were designed for, but not 40M and definitely not 75M. A Fan or maypole is a vastly superior low band, low budget multiband antenna.

That's it for me
Cheers
de NO6L
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by EX_AA5JG on March 24, 2009 Mail this to a friend!
NO6L wrote: "As for a G5RV, I don't even consider these "antennas" on 40 and 75. Every station using one I hear, without exception, running over a kilowatt sounds like they're doing 100 watts into a flat top or V."

Sorry, but my experience is different on this one. I just finished up my 5BDXCC using 100 watts and a homebrew G5RV type antenna. I am now up to around 110 countries worked on 80m, barefoot. It does perform, but not as good as some of the 80m designed antennas. Still, it will get you DX without a kilowatt.

73s John AA5JG
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by EX_AA5JG on March 24, 2009 Mail this to a friend!
NO6L wrote: "As for a G5RV, I don't even consider these "antennas" on 40 and 75. Every station using one I hear, without exception, running over a kilowatt sounds like they're doing 100 watts into a flat top or V."

Sorry, but my experience is different on this one. I just finished up my 5BDXCC using 100 watts and a homebrew G5RV type antenna. I am now up to around 110 countries worked on 80m, barefoot. It does perform, but not as good as some of the 80m designed antennas. Still, it will get you DX without a kilowatt.

73s John AA5JG
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N4KC on March 24, 2009 Mail this to a friend!
Didn't mean to re-ignite the G5RV wars! In my experience, it's a very good 20 and 40-meter antenna, and decent on a couple of other bands. I did say, by the way, that it can be made to work on lots and lots of bands with a good enough matching device, just as any batch of wire can. But it is not a real good all-band antenna.

And NO6L, thanks for the nice comments. And I did say, "As with most antennas, the higher in the air you can get a dipole, the better, if you want to work distant stations. You will make contacts, though, if it is just above head high, and in some cases it actually works better over closer range than if it was in the clouds." I deliberately avoided going into NVIS--beyond the scope of this article, I think.

Don N4KC




 
Top 5 Get-On-the-Air-Quickly Antennas  
by 2I0VFO on March 24, 2009 Mail this to a friend!
http://www.iv3sbe.webfundis.net/ This is a quick antenna to erect and works well and no radials if you wish and a good portable antenna.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by NH6EV on March 24, 2009 Mail this to a friend!
Very good article. With all the fancy store bought ham rigs we use, antennae are a way to experiment. I use a G5RV and like it, I bought it on EBay cause it was cheaper than buying the separate parts. I had a vertical years ago made out of old CB antennas that was perfect on 15 and 40 meters. To much fun. I don't get on enough these days.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by VE3FMC on March 24, 2009 Mail this to a friend!
Very good article. I have used just about everyone of the antennas you described. My first HF antenna was a full wave loop for 75 M. It was low to the ground and I still managed WAS 75 Meters with it and 100 watts.

My next antenna project will be a Hustler 4BTV and I have gained a lot of knowledge about the radial setup from other 4BTV users on eHam.

For once there was no flames in this thread!
 
Top 5 Get-On-the-Air-Quickly Antennas  
by OLLIEOXEN27 on March 24, 2009 Mail this to a friend!
At my qth all five of those antennas suck. Someone should do an article on the effects of moist foilage (tree branches, shrubs, leaves, vines, potted plants) on RF wave propagation. I haven't seen ANY articles on it however at my current qth I am unable to qso using a killowatt and a three element beam to my neighbors qth a half mile away.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by KG2AF on March 24, 2009 Mail this to a friend!
Well Done! Thank you for a fine article.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by K7LA on March 24, 2009 Mail this to a friend!
Nice read. Thanks.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by AB0RE on March 24, 2009 Mail this to a friend!
Great article! I'll be bookmarking this one. Must-read material for new hams. Thanks!

73,
Dan / ab0re
 
Top 5 Get-On-the-Air-Quickly Antennas  
by K0DCH on March 24, 2009 Mail this to a friend!
Excellent article, Don.

A couple of comments here have mentioned the absence of the long wire antenna. I think it was reasonable to not include in this article, since a long wire (in my experience) requires an excellent ground system to avoid RF in the shack.

Getting a long wire to tune up and work without stray RF may not be the easiest way to get on the air quickly.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N3OX on March 24, 2009 Mail this to a friend!
"NO6L wrote: "As for a G5RV, I don't even consider these "antennas" on 40 and 75. Every station using one I hear, without exception, running over a kilowatt sounds like they're doing 100 watts into a flat top or V." "

It's not the fault of a real 102' G5RV with proper matching section, low loss coax, and a decent tuner.

Some is probably the fault of manufacturers who intentionally add losses to make their antennas easier to match on every band using just the internal tuner on a typical autotuning HF radio.

Some is probably the fault of the 15 foot high installation height that is really too low for either band and leaves 15 feet of line laying on the ground.

Some, in homebrew versions, is probably the fault of crappy baluns.

All in all, I think it's easy to burn 10-12dB in something that someone somewhere called a "G5RV" that may also be installed poorly because it's a first shot at getting an antenna up.

73
Dan



 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N3OX on March 24, 2009 Mail this to a friend!
"But with an 80M "V" only 20 to 30 feet high your signal will propagate almost straight up and down to the other side of a mountain. "

While that's true, you can take it up to a quarter wavelength high before you lose maximum gain straight up, and you'll just get louder as you drop ground loss.

It's only really important, when you're starting out, to know about 40m NVIS if you're going to install your antenna higher than 35 feet, and only important to know about 80m NVIS if you're going higher than 70 feet.

On the bands where NVIS works, most new hams end up installing antennas with maximum gain straight up *anyway* just because they don't have very tall supports available, or as someone has posted here, they haven't figured out quite yet how to get a line into the ones they've got.

So it's a good point but probably doesn't need to be emphasized much here. It will be rare for a brand new ham, especially in the audience of this article. to end up with a weak signal problem because of a too-high antenna installation.

To add to the problem, if you research NVIS on the web you start to get people talking about how it's better (or good enough) to use lower antennas, and they base their argument on a MININEC model, which basically treats the earth in the near field as if it were silver plated.

I don't know about you, but if I install a 40m dipole 6 inches above the earth and measure its feed impedance, I don't find 1.5 ohms, and I don't find the straight-up gain to be 11dBi like EZNEC predicts for MININEC earth. 150 ohms and -8dBi is more like it (Real/High Accuracy 0.005S/m )



73
Dan



 
Top 5 Get-On-the-Air-Quickly Antennas  
by VE7RWN on March 25, 2009 Mail this to a friend!
A very well written article, Don. I especially liked your pros and cons, based on real world installations. I too have used all of your examples, with various installation comprimises. The best loop setup was on the roof of a commercial building, which had a steel structure under the roofing membrane. The loop was held up in four corners with 1.25 inch wooden dowelling, 14 feet high. The wire was only eight feet above the roof at the lowest droop in the wire. Cut for 3.729 mhz, it worked very well, and allowed me to work South America on 80, as well as great local performance. Coax fed in one corner, without a balun, and a tuner to keep the rig happy, it was one of the quickest installs I ever put together, and more importantly, I was happy with the results.
Thanks again for the article, it will be bookmarked to pass on to others.

73, Rob, ve7rwn..
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by G3LBS on March 25, 2009 Mail this to a friend!
Horrified by mention of coax and baluns - I agree with advice to use ladder line all the way to a true link-coupled tuner, even for a 102 ft top 'G5RV'.
Try me on 40 or 80 with my G5RV - or on the main lobe on 10? See Cebik articles for forward gain in main lobes of G5RV as frequency rises! Though main antenna is tree-suspended boomless spider quad of course. Tennis ball launcher and link-coupled true balance Johnson Kilowatt Matchbox were my best buys, also MFJ dual RF ammeter.
W2/G3LBS
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KG4TKC on March 25, 2009 Mail this to a friend!
Another most excellent article by N4KC to join his other fine articles in the archives. I feel this statement made by N4KC in one of his replies really hit the nail on the head. We should all remember it. It goes___"Keep the suggestions coming...end-fed wire, fan dipole, OCF dipole...all good suggestions and will get folks thinking. Thinking and building. Building and talking.___" My only question for Don is,,Have you been reading Socrates lately,,:)
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by W8AAZ on March 25, 2009 Mail this to a friend!
With modern rigs, I have had reasonable results on like, 40M SSB with a random wire and an appropriate tuner to match it to the rig. Usually tried to get the wire as long as possible in temporary hookups, something like maybe quarter wave or half wave. Or truly random. Not ideal but will radiate a sig. and probably outperform a truly compact antenna like a mobile whip. My problems now with antennas are not so much related to amount of real estate, as obstructions and hazards that leave a reduced space for anything. I did try a random SW rec. antenna as a novice. Not knowing what I was doing exactly, I got poor results.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KA4KOE on March 25, 2009 Mail this to a friend!
What about the extended double zepp? Why did this one get left out????? IT HAS GAIN, and is only a little longer than a parallel feedline fed doublet.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N4KC on March 25, 2009 Mail this to a friend!
K0DCH: exactly why I did not include the end-fed long wire...clearly the simplest HF antenna. But it must be fed against a good RF ground or it can cause problems, as you note.

OllieOxen27: you really should not discontinue your medication without first consulting your physician.

KG4TKC: yes, Socrates was a real advocate of the open-wire-fed dipole, using a couple of hemlock trees for support.

NOTE: the URL is busted above for the loop article on my website. Dang "S" has to be capitalized to work. The correct URL is:
www.donkeith.com/n4kc/Skywire.htm

73,

Don N4KC
www.n4kc.com
www.donkeith.com
www.n4kc.blogspot.com


 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N4KZ on March 25, 2009 Mail this to a friend!
More top-notch work, Don, as always. Congratulations. I would also include an end-fed wire on the list of easy-to-erect antennas that can work reasonably well if you can avoid RFI problems by using a counterpoise on the antenna coupler. My first antenna as a novice 40 years ago was an end-fed wire on which I worked the world before erecting better antennas.

I agree that some folks seem intimidated by erecting an HF antenna when, in reality, virtually anything will work -- to some degree. And something is always better than nothing. Try it. If dissatisfied, play with it and make modifications. Don't wait until you find the "perfect" HF antenna because it doesn't exist. They all have performance pros and cons. Erecting even a modest antenna and getting on the air is always more fun than erecting nothing and just staring at that non-functional rig!

73, Dave, N4KZ
 
Top 5 Get-On-the-Air-Quickly Antennas  
by N6CIC on March 25, 2009 Mail this to a friend!
Very nice article which I am sure will encourage many new hams to get something up in the air (or in the attic). For years I threw up all sorts of dipole configurations because I lived with a lot of trees, and I had a great time on the air. Now I live on the edge of the Mojave Desert, so ground mounted verticals have to do for me. But I have a lot of fun adding more and more radials! Again-thanks for a fine article.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by AB7E on March 25, 2009 Mail this to a friend!
To OLLIEOXEN27: Anyone ignorant enough to blame foliage for not being able to be heard a half mile away with a kilowatt on HF into ANY kind of antenna probably doesn't deserve to be heard anyway. Your coax would almost have to be shorted to a good earth ground for that kind of result.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by K8QV on March 25, 2009 Mail this to a friend!

Ollie - PLEASE take your meds.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by WB4LFC on March 25, 2009 Mail this to a friend!
Great article Don.Lots of information for beginners or old hams.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by NO6L on March 25, 2009 Mail this to a friend!
>by AA5JG on March 24, 2009
>Sorry, but my experience is different on this one. I just finished up my 5BDXCC using 100 watts and a homebrew G5RV type antenna. I am now up to around 110 countries worked on 80m, barefoot. It does perform, but not as good as some of the 80m designed antennas. Still, it will get you DX without a kilowatt.

I respect your opinion and your accomplishments. However, I can't help thinking if you'd have used an antenna designed for 80/75 that is resonant on that band you would have achieved these stats sooner, without the headaches of worrying about open line feeder and needing a link coupled tuner. "Physics don't lie." At any rate, good luck to you in radio sport and catch ya' down the log.

>by N4KC on March 24, 2009
>Didn't mean to re-ignite the G5RV wars!
>I deliberately avoided going into NVIS--beyond the scope of this article, I think.

Not sarcastically, I didn't know there even was a G5RV war. The dumb things people fight about, who'd ah thunk.

You're probably right, too much to digest. Ok, maybe next time, or I or someone will cover it. Cheers.

>by NH6EV on March 24, 2009
>...With all the fancy store bought ham rigs we use, antennae are a way to experiment...

And don't forget other station accessories, everybody, antenna switches, tuners, QRP rigs and even amps. "To keep your mind sharp, read something or build something."

>by OLLIEOXEN27 on March 24, 2009
>Someone should do an article on the effects of moist foilage (tree branches, shrubs, leaves, vines, potted plants) on RF wave propagation.

That's not a large article, I can cover it in one line, "The effectiveness of RF energy to propagate through foliage is directly proportional to the density of said foliage and is also directly proportional to the frequency of the RF energy".

Done.

And if you're having that much of a problem with HF around foliage, you've got other problems.

>by N3OX on March 24, 2009
>...It's not the fault of a real 102' G5RV with proper matching section...

I have to disagree, I've worked many stations on 75/80 and the G5RV is always outperformed by a flat top or V. With the "headache inducing" open line matching section properly routed and especially if it's not.

>by G3LBS on March 25, 2009
>...Horrified by mention of coax and baluns - I agree with advice to use ladder line all the way to a true link-coupled tuner,...

Why would you be horrified by coaxial cable and baluns? And why would you foist all the extra problems with using LCTs and open feeder on a beginner? Do you want them to leave HF for good? Frankly, I'm not paid enough to do a walk-around to inspect open line feeder before going on the air, especially after bad weather. Coax was invented to eliminates that. Take advantage of it.

>...Try me on 40 or 80 with my G5RV...

Instead, deploy a resonant 40/80M fan dipole broadsided the same direction and compare average performance and the G5RV will be history 40M and below.

>by KA4KOE on March 25, 2009
>What about the extended double zepp? Why did this one get left out????? IT HAS GAIN, and is only a little longer than a parallel feedline fed doublet.

That is not a beginners antenna, they're HUGE on low HF. As you said, they have gain, that means your signal will be much weaker off the ends. A beginner would want a more general purpose antenna.

Cheers to all and 73,
de NO6L
/end of line
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by OLLIEOXEN27 on March 25, 2009 Mail this to a friend!
thanks N6OL. that's what a suspect.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by VE3FMC on March 25, 2009 Mail this to a friend!
by OLLIEOXEN27 on March 24, 2009
At my qth all five of those antennas suck. Someone should do an article on the effects of moist foilage (tree branches, shrubs, leaves, vines, potted plants) on RF wave propagation. I haven't seen ANY articles on it however at my current qth I am unable to qso using a killowatt and a three element beam to my neighbors qth a half mile away.


Ollie you better check your coax runs. My 80 and 40 meter dipoles run right through the middle of maple trees, a catalpa tree and another maple tree. No problems here on HF.

I have had home made 20/17 M verticals that I hung off the branches of one maple tree. They worked fine.

So I think you have other major problems.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by NO6L on March 25, 2009 Mail this to a friend!
>by OLLIEOXEN27 on March 25, 2009
>thanks N6OL. that's what a suspect.

What's that mean?

/end of line
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by TIMEWILLTELL on March 26, 2009 Mail this to a friend!
Great article, very informative and a good enough to print off and save.

Bravo.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by VE6PKR on March 26, 2009 Mail this to a friend!
Great article. One antenna that I would include in a list of "simple antenne" is the vertical delta loop. All you need is a single overhead support, and the bottom two can just be ropes from free-sliding insulators to the ground. I used a pair of these for Field Day last year, and they were great. I pre-cut my two lengths of wire and put them on sonotube spools (no kinks that way). I started with 20m, and threaded that wire through an insulator hung from a rope between two trees, then through a dog-bone on each side, and to my tuner's balanced output in the middle. After raising the overhead support and adjusting the stakes, I had a good equilateral triangle that was very easily tuned with my tuner. This was a one-man job, and when the sun was starting to set, I simply replaced the 20m wire with the 40m one, and I was back on the air on a new band.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by KC2WI on March 26, 2009 Mail this to a friend!
Is the G5RV perfect? No. But considering I probably spent less than $25 for materials and have ben using it for 20 years, it's a great antenna.

Mine works well on 75 and 40. I can use it on all bands 75-10 including 60M with a transmatch. Even below 3.5 MHz on MARS frequencies. don't think it works that well on 10 meters. If you're going to do anything serious on 10 meters, just build another dipole. At only 5 meters total length probably almost anyone who has space for a G5RV can also put up a 10 meter dipole. Or build a simple 10M vertical for great DX.

If you don't have space for a full-size G5RV but want multi-band tuneability, try the half size. I've even been able to match one up on 75M but obviously it doesn't work that well.
 
Top 5 Get-On-the-Air-Quickly Antennas  
by KB2HSH on March 27, 2009 Mail this to a friend!
OK...now without the censoring...

HAS ANYONE USED AN ISOTRON? I WANT TO BUY ONE, AND AM WONDERING IF ANYONE ELSE HAS USED ONE.

God, this website is ridiculous.

KB2HSH
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB1QBZ on March 27, 2009 Mail this to a friend!
>>HAS ANYONE USED AN ISOTRON?

Yes, I've used one. Thanks for asking.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB2HSH on March 27, 2009 Mail this to a friend!
QBZ:

Thanks.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB1QBZ on March 28, 2009 Mail this to a friend!
So what's the betting??

Is HSH going to:

1. Come back and actually ask a meaningful question?

2. Come back and ask a totally unmeaningful question (e.g., is it a "good antenna")?

3. Go away in a huff and declare that this site is worthless?

4. Ignore the fact that there are at least 58 posts on this site describing peoples' experiences with Isotrons?
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB2HSH on March 28, 2009 Mail this to a friend!
No, it's my fault. I didn't quite elaborate my point well enough.

Have a great weekend.

BTW...I always like hearing from Isotron users...I have been wanting one for a while, so...I have been applying the whole, "your mileage may vary" concept.

John KB2HSH
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB1QBZ on March 28, 2009 Mail this to a friend!
Fair enough.

There are 58 (I think) reviews in the Reviews section of the e.Ham (Bilal Isotron).

Over the past six months, I tested an 80/75 meter Isotron for some ARES work. Two types of tests:

(1) Assuming a disaster knocks out the 80/75m dipole at city hall, how quickly could we get an Isotron deployed from the roof (about 100' above surrounding ground) so that we could communicate with the state EOC (about 100 miles away). Part of this test was, essentially, can the 80/75m Isotron be stored someplace reasonably safe inside city hall (which is the local EOC)?

(2) Would the Isotron be suitable for quick set-up portable operations in the field, and could it hit the state EOC as well as our local EOC.

The answer on part (1) was pretty positive. As long as we had it pre-configured, we could:

- store it someplace safe (the Isotron and the mast on which we were going to mount it),

- get it deployed quickly (physically installed and tuned), and

- hit the state EOC reliably (about 100 miles away), with results that were either the same as the dipole, 1 S-unit down from the dipole, or 1 S-unit up from the dipole (which was mounted lower-down on the building). Being on top of a 110' high building probably didn't hurt - especially at night when band conditions on 80/75 make it difficult to hit the state EOC with a dipole at 35 or 40' in the air.

The answer on part (2) was not as positive.

- Tuning is fairly tempermental with respect to location/surroundings/set-up, including things like length of coax, height of antenna, height of mast, where the antenna sat on the mast, and quality of ground connection. Thus, in the field, where you never know what you're going to have for mounting nor what your surroundings would be, it became a lot of work to tune it every time it was deployed.

- There are a number of parts in the Isotron, and some of them are small and thin (NOT particularly flimsy, but not big hunks of rock-solid iron). That was a problem for carrying around, having sometimes ham-handed (so to speak) hams trying to tune it, and throwing around in the backs of cars.

Once installed and tuned at a portable site, it gave a reasonably good signal. In the field, we couldn't compare it against a dipole because we just had no way to string 136' dipoles in the field. During the day, as expected, we were able to hit the state EOC reliably and with a strong signal with the Isotron on a 10' mast. At night, from ground level, we typically couldn't hit the state EOC, but we weren't expecting to be able to. However, we were able to hit the local EOC and we did have some fun with QSOs out in the 500-1000 mile range.

I did try it from my home on a 10' mast. Definitely not as good as my Cobra Ultralite Jr (about 35' up). Typically 1-2 S-Units down. No problem hitting the state EOC during the day, not reliable for hitting the state EOC at night (neither is my dipole). But it did get out and I did have a number of good QSOs.

I also tried it from ground level at city hall. The results were similar to the results from my home.

In a thread in Elmers, someone gave me hell for using an Isotron as a backup antenna in an ARES test, but never answered my question regarding what he would suggest we use in a circumstance where we need to get something deployed quickly from city hall and stringing another 80/75m dipole is not practical.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB2HSH on March 28, 2009 Mail this to a friend!
QBZ:

AWESOME!

The main, underlying idea (and I probably am asking in the wrong forum/venue) is that I am writing a piece for a club newsletter...and since the topic was antennas...and it was a LIVE topic, if I put out a feeler, I would get timely responses.

(And I am with you...it would seem that an Iso would be a great backup...hell...ANYTHING that could be loaded up in an emergency would be beneficial)

At some point, could I e-mail you directly if I have more questions??

John KB2HSH
 
Top 5 Get-On-the-Air-Quickly Antennas  
by 2E0MCA on March 29, 2009 Mail this to a friend!
Very good article. I know someone who was looking at the end-fed wire option, but with the shape of his garden the horizontal loop may be another option - I'll point him in this direction. Always nice to read the responses, and listen to the views on the G5RV and its derivatives.

I use a 1/2 size G5RV and have been very pleased with the results. It's a good compromise antenna, with the emphasis on the compromise. My instructor (elmer) swears by them as a good starting point for the beginner - especially as gardens are quite small here in London. They are simple and effective, though I'd be first to admit that a pure dipole would probably perform better for which ever band you choose to cut it for. The 1/2 size tunes up well on 40, 20, 17 and 10M and I have had good results using it on these bands. It's not so good on 15M (this is a known problem area on the full G5RV) and 12M. Don't tune it on 80M unless you want to fry your pets;-)

I cleared my DXCC (still waiting for the QSL cards and LoTW to catch up ;-)), using a maximum of 50W within 2 years of getting licensed with this antenna, so it's not a bad option bearing in mind that the first 6 months were at 10W. For the purist it's not a G5RV as it uses a coax feed to the ladder line, but it works well for me.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N3OX on March 29, 2009 Mail this to a friend!
".I have been applying the whole, "your mileage may vary" concept.
"

What does that mean with antennas?

To me, "your mileage may vary" means "my experience will not be consistently reproducible at your shack" And that's why I don't like Isotrons and other teeny tiny antennas that excite the feedline.

And yeah, I know it's popular to pretend they don't excite the feedline. But given the size of the 75/80 Isotron and the wavelength of that band, it's totally impossible for it to be more than a fraction of a percent efficient without considering the feedline radiation.

And maybe you can optimize the feedline radiation to put out a pretty acceptable signal, but you have to use the same feedline and same surroundings each time.

"Your mileage may vary" means "no one ever gets the same results when they use this antenna"

The reviews for the Isotron vary from "It's great on 80m, why would I use something bigger?" to "It's 20dB down from my MOBILE antenna"

As far as I'm concerned, using an Isotron in an emergency situation is like using hemp rope in a fire escape ladder. Yes, if it's your *only* option, by all means, use it, save lives, damn the risk. But planning to use it ahead of time instead of figuring something else out with more predictable performance is not responsible.

Yes, someone might have been able to save the mother and her baby and even go back for the dog using a flammable ladder once, but that doesn't mean you shouldn't plan to make your real fire escapes out of steel most of the time.

"In a thread in Elmers, someone gave me hell for using an Isotron as a backup antenna in an ARES test, but never answered my question regarding what he would suggest we use in a circumstance where we need to get something deployed quickly from city hall and stringing another 80/75m dipole is not practical."

I don't know if that was me or not, maybe was.

I would suggest you install a permanent, ice-proof (modestly!) shortened 75m antenna on top of the city hall building.

You build an inverted vee out of 1/2" wire rope to stout supports on the roof, it won't come down.

Maybe you don't have space for a full size dipole, but that doesn't mean you have to use a five-thousandths wavelength long antenna instead. Maybe you load it with inductors in a box in the middle, with tap points so you can take care of the ice detuning if necessary.

If your Isotron hits the State EOC from the roof of that building, your shortened, two-ton-ice-loading-capable antenna will do a better job. A much better job. You might even be able to relay for other people's tiny antennas.

Look, you want to pretend like an Isotron is a good choice in an emergency, fine, but I maintain that it's a bad idea to be recommending antennas where even the reviewers notice something like a 40dB difference in their home station use (as good as my Windom vs. 20dB down from my mobile).

If you want to keep it in a closet in city hall as an antenna of last resort, I can get behind that. And it sounds like you've done your homework as far as getting reproducibility in your city hall setting, and that's great.

But by itself, it is an incomplete antenna.

At the very least, please recognize that the Isotron is basically a fancy tuning network for your coax and/or mast, and that a short vertical on the roof the same height as the mast with a tuning network at the bottom would equal or exceed its performance while being easier and safer to erect on an icy rooftop. A solid ground to metallic structures or added radials on the roof for your real tuning unit (which could be a simple homebrew that I would be happy to help you with) could pop your signal up 10dB.

Maybe it wouldn't. Maybe you lucked out in mast and feedline length. But, maybe it would literally make the difference between night and day (communication)

I apologize if you think I'm being insulting or offensive. It's easier for me to shut up about poor, small, overhyped antennas that don't actually do the job they say they do if people are just shooting themselves in the foot as far as DXing and ragchewing go, and even then I want to say something.

But this is different, and I just can't let it go. An Isotron is not a real antenna. It can be used as part of a marginally effective antenna system sometimes, but I think you should, if nothing else, please refrain from recommending it to others for anything except literal last resort emergency communications.

73
Dan










 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB1QBZ on March 29, 2009 Mail this to a friend!
>>"In a thread in Elmers, someone gave me hell for using an Isotron as a backup antenna in an ARES test, but never answered my question regarding what he would suggest we use in a circumstance where we need to get something deployed quickly from city hall and stringing another 80/75m dipole is not practical."

>>I don't know if that was me or not, maybe was.

>>I would suggest you install a permanent, ice-proof (modestly!) shortened 75m antenna on top of the city hall building.

>>You build an inverted vee out of 1/2" wire rope to stout supports on the roof, it won't come down.

It was you -- and this response in this thread is exactly the kind of information I was looking for. I haven't previously heard of wire rope -- nor did any of the city's emergency people suggest it to me.

I did a quick calculation and an inverted v at a 120 degree angle gives me about a 35' mast and about 112' across. That may fit. I'll have to see if there are sufficiently stout supports. Can I run the wire rope right down to roof, or is there some minimum distance above the roof for the termination points?

"... a short vertical on the roof the same height as the mast with a tuning network at the bottom would equal or exceed its performance while being easier and safer to erect on an icy rooftop. A solid ground to metallic structures or added radials on the roof for your real tuning unit ... could pop your signal up 10dB. "

There's an idea that sounds very attractive. I'm a bit obsessed with the idea of having something that I can store indoors and not have outdoors in the storm (whatever kind) when the storm hits. Of course with my luck, whatever floor of the building it's stored on will be damaged, but the roof won't be. Anyway, did you have a specific "short" vertical antenna in mind? When you say "short vertical ... the same height as the mast...", that makes me think of things like the Outbackers or Hamsticks or even a Buddipole or MP-1, as opposed to the Butternuts or Hustlers, etc. (which I think of as "full size" verticals).

At any rate, thanks for the idea about the wire rope -- I'll call my contact at city hall about supports tomorrow.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N3OX on March 29, 2009 Mail this to a friend!
"I did a quick calculation and an inverted v at a 120 degree angle gives me about a 35' mast and about 112' across. That may fit. I'll have to see if there are sufficiently stout supports. Can I run the wire rope right down to roof, or is there some minimum distance above the roof for the termination points? "

That would be fantastic. That's actually going to be very close to resonant, and on top of a 110 foot building might take you from being just barely being able to hit the State EOC to being New England's premier Ice Storm Relay station. And you don't have to put the ends much above the roof especially for an antenna that gets infrequent use. Keep a foot or two for safety; you'd want out -of-reach if people could touch it when it's energized, but this is an emergency antenna not a club station antenna.

"I haven't previously heard of wire rope -- nor did any of the city's emergency people suggest it to me. "

They're not antenna guys nor mechanical engineers I suspect (not that I'm the latter). Wire rope is big heavy cable... it's usually made of something like galvanized steel... and usually used for holding things up, but there's no real reason not to use it for antenna conductor.

Of course, if you want it to stay up under heavy ice loading, the wire is only part of the issue. You're going to need a stout, heavy mast ... to get to 35 feet you'll need a tower.

But I think a dipole even 10 feet or 15 feet above the roof at the apex could do the trick, and at 10 feet or 15 feet a 3 inch or so steel mast should do it.

This is all expensive stuff, so it does depend on your budget. And it depends on what you're allowed to put up on the roof and allowable roof loads, but if you really want an effective antenna for the aftermath of an ice storm, building it a tad stronger than the power lines is one way to do it.

"
I'm a bit obsessed with the idea of having something that I can store indoors and not have outdoors in the storm (whatever kind) when the storm hits."

That makes sense, especially on a small budget. You know, having a solid 20 or 30 foot mast in the middle of the roof with NOTHING on it but a stout sheathed pulley and a strong rope might be one way to keep a normal inverted vee in the closet and have it go up in a snap after the storm.

All in all, the horizontal on top of a tall building is probably the best bet for regional communications.

"When you say "short vertical ... the same height as the mast...", that makes me think of things like the Outbackers or Hamsticks or even a Buddipole or MP-1"

In my opinion, there are no really good commercial short antennas for 80m.

Hams like to buy six foot and eight foot antennas for a band with a 260 foot wavelength.

So that's all they sell. And hams don't mind changing a coil tap every once and a while, but they don't want to have to retune every 3kHz. So they use intentionally lossy loading structures. The upshot is that it's hard to buy a commercial 75m antenna of relatively small size that's better than 1% efficient.

And I have to confess that I'm not necessarily thinking of certain butternuts and hustlers as "full size" but you do have to get something out on the roof

Basically, the taller the better, but doing it right with maybe with a small capacitance hat on the top and a coil at the bottom could be the way to go. Can it be 10 feet tall? How about 15 ? You'd have to build it but I would be happy to help regarding the electrical and physical design.

If the expectation is that you will wait until after the storm to put it up, you could have a 40 foot antenna that one person could safely erect if you just had a socket for a 40 foot spiderbeam pole permanently attached to a railing up on the roof.

http://www.n3ox.net/projects/lowbandvert

is an antenna I built and could easily raise by myself in about two minutes from the collapsed position once the bottom section guys were staked into place, and if you had a metal pipe to drop it into you wouldn't have to do that part.

The antenna could be fed against some metal on the roof or some radials that you lay down permanently or temporarily (though I'd suggest the former)

The coil you need to match it to 50 ohms is laid out on my website.

You can use a 6 foot whip if you really think that's the only thing that could be safely erected by one person within your constraints and budget, but if your city emergency folks want a really effective station with some extra "oomph" when you really need it, I think you should look elsewhere than the ham portable antenna market.

Honestly, small ham antennas are designed for guys at picnic tables having a fun weekend on the radio, and they can be pressed into service in an emergency and are way better than nothing, but they're not made for reliable power-efficient communications on 75m.

73
Dan


 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by KB1QBZ on March 30, 2009 Mail this to a friend!
Now you've got me thinking about some other possibilities. I've been looking at The Mast Company and Max-Gain poles for something at home, and those might be possibilities for city hall (along with Spiderbeam poles -- I'll have to find out more about them).

By the way, it's not clear to me from the picture of your vertical what it is that you use to attach the antenna wire to the inner pole. I think the text says a grommet -- if so, how do you get it to stay up on the top of the pole without either sliding down or coming off, and how do you get the wire to stay attached to the grommet?

There would be the opportunity to put a loop up on top of the building (around 80x50x80x50). How low above the building could we go with something like that? And would it be possible to have a loop with the air conditioning equipment and/or the elevator house encompassed within the circumference of the loop (they would stick up above the top of the loop unless we had the loop at least 15' up. I'm thinking of something simple that we could erect after the storm and not something that would be expected to stay up during a storm.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N3OX on March 30, 2009 Mail this to a friend!
Grommet's tight fitting to the pole tip, wire loop wrapped around and soldered (little smelly, but worked). The collapsed pole picture shows it.

The pole is tapered too. Friction and taper do the work of keeping it from slipping down. Then the wire is just wound in a loose spiral around the pole (about 1 turn per section) by just rotating each section as I put it up.

"There would be the opportunity to put a loop up on top of the building (around 80x50x80x50). How low above the building could we go with something like that?"

You'd just have to try it. I think you might get pretty good performance even just a couple feet above the edge of the roof. The stuff sticking up through the middle shouldn't matter much, probably just raises the resonant frequency of the loop a tiny bit if anything. Hard to say until you try it though. I don't think closeness to the roof will cause a huge efficiency penalty.

I think that sounds like a good idea... some posts in the corners that you could clip to.


73
Dan

 
The Quarter Wave Vertical  
by N2EY on April 4, 2009 Mail this to a friend!
can be a good antenna in many situations. The article mentions it in terms of a wire from a tree, but there are other implementations that work well.

For example, at my old QTH there was a detached garage with a flat roof. I built a 20 meter vertical out of two pieces of EMT conduit overlapped and bolted together, and a simple wood-and-plastic clamp arrangement for the base. The elevated radials were light-gauge (#18?) enameled wire, some on the flat roof, others out to fence posts and small trees in the yard. The bottom of the vertical was about 10 feet up, and you couldn't see the radials unless you really looked for them.

The whole thing cost me maybe $10 but the results were as good or better than any manufactured quarter-wave vertical, be it a trapper or SteppIr. The main difference was that mine only worked on 20 meters.

73 de Jim, N2EY
 
Top 5 Get-On-the-Air-Quickly Antennas  
by OLLIEOXEN27 on April 4, 2009 Mail this to a friend!
At my qth the end fed half wave sloper along with a quarter wave counterpoise and a tuner beats all the above except for the G5RV which I haven't tried yet. All the rest were deaf, mute, or fubar.
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by WA2JJH on April 6, 2009 Mail this to a friend!
It is always good to get some simple antenna design/varients that have been known to work well in a pinch or on a budget.

Making your own or making old classics work with less then ideal cndx
can be fun.

Many new hams may have to resort to cheap wire dipoles, sloppers, inverted V's,exc.

I am shocked by how expensive antenna's made by the few remaining
antenna corps.
I wanted to design a 10-80M vertical ussing an old classic from a 1972 Lafayette Radio catalog and a roof mounted tapped coil ATU.

The Trapless 18V was a nice simple 18 foot vertical, that USED TO sell for $30. It worked great 10-20M with a simple counterpoise or a few radials cut for bands below 20MHZ. The antenna came with a base mounted loading coil.
Rigs back then did not have built in ATU's. One would put the aligator clip on the coil tap for the band to be worked.
Even if you just used a drop down single wire counterpoise,(10-20 feet) you would do just as good or better than the ham that used a 5 trap antenna. Assembly and storage WAS DONE IN MINUTES.

I thought I may just buy this antenna again. Biuld a WX proof box for the low band coil taps. Use simple 4 conductor multicore rotator wire to relay select 1 of 4 coil taps. Simply use 12V to to one of the four wires. This would kick in inductance at the base of the vertical.
The right tap tp get you in the ball park. One could just use the rigs ATU to get a nice low SWR.

The 18V are hard to find. The New cost is over $100. Sure thier are many 5 banders offered for $300+ . They need radials and or cointerpoise just as much as ANY dipole like antenna

I have found putting 4 or 5 sections of 4 foot PVC mast up a decent antenna. I simply use a TAPPERED HELICAL radiator. The tapper is wide and is almost linear for up to 10M. I then coil 1-3 foot sections.
I can enough wire around the fiber glass mast to set down to 80M resonance. I sometimes will add capacitive hats every 8 foot of coil.
No big deal. Just solder some 12 guage copper wire perpendicular to the vertical running up. One can use old thown out 4 foot CB whips too.
I like the ones that are loaded for 10M. Cut the 4 foot sections in half,
One ends up with 2 foot cap hat elements loaded with 4 foot of wire.
For a simple trapless vertical, the capacitive hats every 8 foot of coil can get you in the 3:1 SWR area for 10,12,15,20,40M bands. Some get fancy and use a vacuum 10-200PF moter driven variable cap at the feedpoint.
Of course one can use an antenna analyser at the antenna feed point, to set the traps/cap hats up exactly. However, get on the air fast is the goal here.

I think the Motorized screw driver antenna's are great. If you have both height above ground and radials, one can have a high performing stealth antenna for apt use.

Home brewing and intstalling antenna's and having a group of hams to help with the BBQ used to be one of the big social things to do back many years ago.

73
 
RE: Top 5 Get-On-the-Air-Quickly Antennas  
by N3OX on April 7, 2009 Mail this to a friend!
"The 18V are hard to find. The New cost is over $100."

Depending on when you priced out the $30 one, that might just be inflation.

You only have to go back to the mid seventies according to this:

http://data.bls.gov/cgi-bin/cpicalc.pl
 
Top 5 Get-On-the-Air-Quickly Antennas  
by KU2US on April 9, 2009 Mail this to a friend!
How about the PAR ELECTRONICS END-FEDS ?
 
Top 5 Get-On-the-Air-Quickly Antennas  
by AA4LR on April 14, 2009 Mail this to a friend!
In reality, there's really only three types of antennas suggested:
1) Doublets - dipoles, open wire doublets and the G5RV
2) Verticals
3) Horizontal loops

All of these antennas can be used successfully by beginners. My comments on each type:

Doublets -- the single most important dimension of a horizontal doublet is the height above ground in wavelengths. These antennas work more effectively if they can be elevated to 1/2 wavelength or higher above ground. That's not always easy to do, especially for the lower bands. Low doublets tend to radiate straight up, which isn't always as effective.

Verticals -- the effectiveness of the vertical comes from a quality ground plane, or vertical separation from ground. You've either got to put lots of radials down, or raise the vertical 1/4 wavelength or so above ground with three or four radials.

Horizontal Loops -- in my experience, these are just as effective as doublets at the same height. The disadvantage is they require twice as many supports. I would recommend you focus on getting two higher supports for a doublet instead. My radio work took a leap forward when I moved from an 80m horizontal loop at 15 feet to an 80m dipole at 45 feet.

--

Another antenna that a beginner might contemplate is the delta or quad loop. I put a 15/10m delta loop in my attic and was generally pleased with the results. Horizontally polarized, they work well for DX if high enough. Vertically polarized works well for DX at more modest heights.
 
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