80m Antenna for small gardens
Posted by g7fek on Wed, 13 May 2009 00:41:24 +0100

46ft multi-band antenna for small gardens by g7fek. Works well on 80m. An excellent DX performer and is an ideal replacement for your half size G5RV...


Many years ago I moved into a house with a small garden of about 45 ft. I needed an antenna system capable of the lower HF bands. The 1/2 size G5RV is a farce on the lower HF bands, as are most of the reduced dipole antenna arrangements so I wanted something that was a similar size but truly resonant so losses were kept to a minimum.

This is the latest version of the arrangement I came up with. For years it became my standard quick and dirty install wherever I have moved.

Several Radio Amateurs have built variations of this antenna and have reported excellent performance on 80m with good DX, especially in such a small space.

Advantages
  • Small size (46ft long x 24ft high)
  • 50 ohm Coaxial Feed
  • Multi-band operation for 80m to 10m
  • ATU less operation possible on up to 4 primary bands (80m/40m/20m/15m)
  • Low angle of radiation dominant (good for DX)
  • Easy to construct and set up

What is it?

Although at first glance this looks like a small "off centre fed" dipole, this is actually a nested Marconi 1/4 wave antenna on the lower HF bands, giving a low angle of radiation and predominantly vertical polarisation, and opposing feed impedance is used to provide automatic band switching without traps. The interaction of the nested elements means that both elements play their part 7MHz and up, with dimensions chosen to provide a good multi-band, low angle antenna. This latest version combines resonance of the horizontal top sections and the interaction between elements and on 10MHz utilises 1/4 wave feed technique similar to that used in the Zepp antenna, for improved multi-band performance.

It is simple and very cheap to build, it is very effective in a small space and will beat a "1/2 size" anything by 10's of dB on 80m while taking up even less space. it is designed to look a bit like a short G5RV so that you can scrap your 1/2 G5RV to build it !!

Performance

My own experiments over the years have shown that, on 80m, this antenna will perform close to a full sized dipole for DX contacts, despite the small size,  because of the low angle of radiation (30 degrees) and full size elements.

As this is a low angle antenna, NVIS (high angle) short skip contacts are only down by around 10dB compared to a dipole. This does not usually matter,  unless the band is in poor shape, because NVIS signals are normally very strong. Remember that a 66ft  Windom or 52ft 1/2 sized G5RV will probably not even work on 80m, and you cannot fit a full sized 80m dipole into a 46ft garden!!.

On higher bands, the antenna performs well too. Low angle is dominant on all bands expect 10 MHz, where the antenna is working as a end fed dipole. (There is a variant by OH5RM for low angle on 10MHz - see pdf doc)

When compared to "straight up" vertical antennas, the combined horizontal and vertical components of the G7FEK antenna still give rise to useful high angle radiation.

Recently, on finding the original text document I created for my packet BBS in the early 90's, I decided to re-publish the design here. Throughout 2007 and 2008 the antenna was optimised using comparison signal reports. This was done at sunspot minimum proving   the antenna is usable under poor conditions.

G7FEK and Computer Modelling...

As no two antenna modelling programs give the same results and it is not possible to model all parameters, computer modelling of antennas only allows for a proof of concept. Thus this antenna was optimised in the real world.

I always advocate building antennas to evaluate actual performance, just as the professionals do. Few amateurs seem to want to build antennas these days, instead preferring to comment on their model data alone. I'm often reading antenna articles with "performance" data derived entirely from modelling software - often after significant number "tweaking". How can you provide performance data on an antenna which has not been built yet?.

In response to your requests, I have included models sourced from other Amateurs. The EZNEC model shows less interaction than actually occurs in real life, but still gives a good idea as to how the antenna works. The MMANA-GAL model appears to be far more realistic when compared to the real antenna and is recommended for a more detailed assessment, plus the full software is free!.

G7FEK Antenna EZNEC VSWR Plot


G7FEK Antenna Downloads

Download the G7FEK Antenna Construction Guide (PDF 600K)

MMANA-GAL and EZNEC files
EZNEC file optimised to also work in demo version of EZNEC

Other links and articles

Tests carried out at Sidmouth Observatory

Tests & modelling carried out by G8ODE Royal Signals ARS (PDF)

VE3SCP is working DXCC on a G7FEK Antenna






Comment by 'Roy, ve2uy' on 15 Apr 2014 - comment
“I have built your antenna last summer and never looked back it works very well. I did have to modify it because I do not have any trees near by, so the peek of the antenna (ladder line) is only at 18 ft. at the peek of the roof. I lengthen the 38ft section to 46ft and the ground radial (elevated about 2ft above ground and 65 ft long (kind of twisted). I also lengthened the short portion to 12ft. I must say that I am impressed, and here are some numbers. 6 meters swr 1.5 80 meters 3.12 to 3.9 swr 1.9 to 1.2 40 meters 7.o8 to 7.25 swr 1.5 to 1.7 20 meters 14.0 to14.3 swr 1.7 to 1.8 15 & 17 meters swr 2.3 I use the auto tuner Same for 10 meters swr 2.3 I use the auto tuner. So I highly recommend this antenna to any one without the space, of course the higher the better. Thanks G7FEK”

Comment by 'Dan mw0uzo' on 16 Jan 2014 - comment
“Installed this at home, absolutely perfect for the space available. Used narrow twinlead, approx 8mm spacing from a g5rv and the copper wire from the same. Changed the height to 5m and extended the main elements to approx 14.4m and 5.5m. Extra length required on top of theoretical might be because of the use of narrow lead. Counterpoise wires are a long one in the direction of the main antenna and some short ones in the direction of the 40m part and some other short ones perpendicular to the main elemenets. Got a SWR of 1.2 on 80m and 1.5 on 40m. Works great too, a nice upgrade from the 80m inverted L I was using.”

Comment by 'Stuart (M6STZ)' on 14 May 2013 - comment
“Mike fantastic design please check my QRZ page where I show my 5 watt operations worldwide from Brazil to Australia & Asiatic Russia all using the fab G7FEK I made the antenna as you described but instead of ladder line being vertical I experimented with it at varying angles up to 45 Degrees. with it at this angle I achieved a contact on 5 watts 5345 Kilometers away........”

Comment by 'GUS VK6WB' on 25 Apr 2013 - comment
“Well just finish built this small garden antenna..its worked great.i use 1:1 choke balun who made by BALUNDESIGNS #1115DT and LADDER GRABBER for the center line http://emtech.steadynet.com/ for 80M i use 2 ground radial and for 40M i use one ground radial also attach to balun i add 10ft, 1" size copper tube hammer to the ground.VSWR very low across 80 and 40M. more gdn radial even worked better. cheers and beers ”

Comment by 'Alex' on 8 Nov 2012 - comment
“hello, ive just finished the top band mod, i had a coil already wound and tested, less than 5 mins ago, what a great match for 1925 and 1.830 am using a FC 902 ATU will switch over to the other bands later, 73 G0DHZ”

Comment by 'Steven VK3FUME' on 24 May 2012 - comment
“I'd like to try your antenna as a dual bander outside the ham bands. I work for an organisation that has use of these frequencies, 3.8 and 5.2mhz. Is it as simple as calculating the 1/4wl for two inverted L's? or is there more to the relationship between the the L's. What would be your starting lengths given the above freqs?”

Comment by 'Mike G7FEK' on 8 Feb 2012 - comment
“This would probably work but I would not recommend attaching the vertical section to the building. This part needs to be out in the clear and away from the shack as it forms a principle part of the radiator. Other builders have used metal support poles with a plastic or wooden top section to insulate the vertical from the mast. This is very effective and provides good support. Look at this example: http://www.qsl.net/ve3scp/ If you run the 38ft section back towards the shack, you can support this end on your building, using the mast at the far end. I hope this helps.”

Comment by 'Kenny' on 8 Feb 2012 - comment
“Hi, I am no expert in fact quite the opposite. I am new to amateur radio doing my foundation course at the moment and i like the look and properies of your antenna. The antenna uses wire feed or ladder line but for better stability and for straight line without sag and tension on the feeder , can i use tubing that is sepperated by a foot or so for the vertical property of the antenna if the uprights are insulated from the ground or attached to the building i wish to use?”

Comment by 'Mike G7FEK' on 8 Feb 2012 - comment
“@PC1MB, Ha Ha Nice QRP working!! For the choke you'll need about 6 meters of coax . Pringles cans may also be foil lined so use something plastic like a soft drink bottle. Take note that the bands are a bit unpredictable at the moment due to solar storms.”

Comment by 'PC1MB' on 8 Feb 2012 - comment
“I raised it tonight. Forgot to make a balun, so I wound 3m of RG58 around a Pringles can as a temporary fix. The antenna needs a little trimming, but I already have low SWR on 40,30,20 and 10 meters without ATU. Surprisingly, 15 meters is much worse than the other bands, peaking at 3:1 SWR, but that's within ATU range. First QSO was Portugal on 40m, 1900km. Report 55/56, had to spell my callsign three times. I was slightly disappointed, until I noticed I was still running the 5 watts I used for tuning... back to 100 should gain over two S-points. Will have more time to play with it next weekend.”

Comment by 'PC1MB' on 6 Feb 2012 - comment
“Hi, Since a fullsize G7FEK is a few feet too long for my back yard, and I couldn't figure out a way to get it much higher up into the tree than 20 feet either, I'm now working on a somewhat smaller variant. Let's call it a 40m antenna for VERY small gardens... I started with a half size G7FEK design; legs for 7 MHz and 14 MHz and just 12 feet tall. Then I lengthened the 14 MHz leg for 10MHz - didn't want to skip that band. That meant I'd still needed the extra wire for 14 MHz, that only just fit in the triangle formed by the 10 MHz section. Then I increased the height of the vertical portion a lot, to about 18ft. That shortened the horizontal top section enough to form a half wave for 21 MHz, where the 7 MHz section is a 3/4 wave, duplicating how your 80m version works for 30m. The 10 MHz leg on my scaled down version will also resonate on 29 MHz, so this variant should cover 40,30,20,15,10 meters. I'll start with three radials, one for each section, maybe add more later. Only 12m and 17m are missing, but I can easily deploy dipoles for those bands, if a good ATU doesn't make enough of a difference. Well, that's the theory, will update when it's up. ”

Comment by 'Scott VE3SCP' on 15 Jan 2012 - comment
“I should also mention that I have obtained DXCC on 80m with 100 watts. Total countries confirmed to date stands at 112.”

Comment by 'Scott VE3SCP' on 15 Jan 2012 - comment
“I thought it was time for an update to my experimenting with the G7FEK antenna. This antenna is SAME antenna I put up back in 2009 when Mike and I performed the trans-Atlantic test. The only difference is this year I am only using 3 elevated radials versus 4 elevated radials in previous years. This antenna is into it's 3rd Canadian Winter and running strong. I got involved in some weak signal work using a digital mode called JT65-HF. This digital mode sends a series of tones that are precisely timed. High power in this mode is typically 30 watts and most of the time only 5-10 watts is used. Over the past week I have worked several countries in this mode with only 15 to 30 watts. Here is a brief overview. ZS2ND South Africa Only 30 watts on 40m CX8AF Uruguay Only 30 watts on 40m G4MPK England Only 20 watts on 40m - he was running 3 watts and ground mounted vertical antenna F5GPE France Only 20 watts on 40m KP4ED Puerto Rico Only 15 watts on 80m LU2XPK Argentina 25 watts on both 15 and 10m (6800 miles) As you can see this antenna radiates very efficiently!! Never under estimate this antenna for DX. 73 for now.”

Comment by 'Stu, G3OCR' on 27 Dec 2011 - comment
“Finally got my telescopic fibre-glass "SOTA-Pole" to stand upright, once the winds dropped and I could adjust the guys! Resonated both bands at better than 1.5:1 right across them, and worked a lot of staions on 40m on the RSARS net, right across England (though with much QRM/QRN, and idiots "tuning up" on the frequency)this aftenoon. Once it's dark I'll try 80m. During the afternoon it was just loud local noise, but now I have a good SWR at the base of the antenna AND in the shack, I'm "quietly confident" that I'll get some good QSOs once night falls. I added a couple of ground stakes near the base of the antenna, and added another surface radial 60 feet long for 80m. It seemed to not matter whether the end of that radial was raised 3 feet for the last 4 feet of the rdial, 3 feet for the last 8 feet, or just left on the ground - why do you suggest raising the last few feet of the radial”

Comment by 'Mike G7FEK' on 13 Dec 2011 - comment
“Hi Stu. If you are running surface radials, why not keep them just above ground and make them 1/4 wave resonant - about 60ft and 30ft respectively and raise the ends to ensure they can resonate. this will ensure low impedance near the operating frequency. Ideally everything should connect at the base of the antenna to coax braid. If you have buried radials some distance away, you should be able to join up to them using a buried wire, but they may be only slightly better than the single buried wire itself, because you effectively have your losses on that one wire as though it was one longer radial, but it will help. Surface radials are better to obtain lower ground impedance with less wires, but only if they resonate as their resistive coupling to ground is very poor. 2 - 4 radials can be extremely effective this way. Assuming you have built the antenna correctly and understand how the vertical section is connected to the coax inner then, If your 7MHz is too high in frequency (most likely), then your grounding at this frequency is very poor. Try improving the ground and/or tune the 7MHz wire length by extending it a little. A downward slope also effectively shortens the wire so you need to compensate by adding some length. I small amount of downward slope is tolerable at the 7MHz end. I hope this helps. All the best,   Mike, G7FEK.”

Comment by 'Stu, G3OCR' on 11 Dec 2011 - comment
“Antenna built and raised to roughly the correct height. Seems to resonate a little below 3.5MHz okay but the WX here in N orthern England has been pretty foul and I don't want to try to start hauling it up and down in intermittent heavy rain and high winds HI. 7MHz doesn't seem to want to resonate anywhere within the ham bands and I'll have to wait until I get the analyser on it. (Due to the way the antenna is erected, with the short "horizontal" part of the 40m section sloping downwards about 20 degrees, this may be relevant) GROUNDING - The antenna has an earth stake at the base, with a 14m length surface radial under the 80m section, and 4m surface radial inder the 40m section. I also have a system of buried grounds/radials at the shack (beyond the end of the shorter surface radial with a ground stake at the shack. This system is not currently connected to the surface radials and ground stake at the 'fek antenna. Before I go any further with the tuning, should I interconnect these? My instinct says "more is better", but I have read elsewhere that surface radials should never be connected to an earth stake "at the far end", which is what this interconnection would effectively do. Ideas please? Stu ”

Comment by 'Jan PA2JJB' on 3 Nov 2011 - comment
“Hello Mike, Last week I built your antenna and I must say, its a very good design, and I coul'd easily tune it up tp 80 and 40M. I tuned it around 3570 and 7060 because I am a CW-fanatic hi hi. This week I tried to implement 160M by experimenting with somme heavey coils from my junkbox. I put 3 in serie 2 big ones with each 21 turns, one with a roller to tune the coil, and one small one with 18 turns. As you can see on my QRZ.com http://qrz.com/db/PA2JJB/?1320308194 its giving, with8 radials of different lenght a very good dip at 1844 KHz, and not to small at all. I'm very happy with this antenna I think we have on Texel-island a very good soil for this antenna, the radials are laid under my wooden fence, to keep my XYL happy hi hi... I worked 160M all around Europe and yesterdaevening EK6RL and EY8MM (5000km), so this modification works GREAT !!!!! The internal tuner of my FT950 tuned this antenna also on the other bands.(when switch to 3.5 and 7Mhz) My goal is to optimise this antenna it in the real world for 160 - 80 - 40 and 30 M's Today I will make a big 12V relais with hugh contacts to short out the coils for 160M when I want to use it as a 3,5 and 7MHz antenna. When this works OK, then I will look for a watertight plastic box to built it all together; coils - relais - coaxconnector and antenna-connections For 40 - 6 M I use my SteppIr and is my best antenna I ever bought and made, till I saw your design hi hi, but in the feature I will compare the both antenna's and I think this vertical giving very good results for the lower bands. Mike I let you know how I expermenting with this antenna and share it with all the other hams who are interested in this fb design 73's Jan PA2JJB Texel-Island EU-038 ”

Comment by 'Tim Taylor (M6AUK)' on 2 Oct 2011 - comment
“Hi Mike - no the inverted V is only about 30' per leg (maybe a touch more) and I haven't been getting nearly as good results off it as I did with the 'FEK'. Thanks for the info re: counterpoise, I can set up a comprehensive earthing arrangement with radials the way I now what to site the antenna, but none of them will run directly underneath it, which was my main concern.”

Comment by 'Mike, G7FEK' on 27 Sep 2011 - comment
“@M6AUK : Hi Tim. The counterpoise is just one method of earth arrangement. You can route it in other directions and it should also work well enough. You can also try earth rods, as used by some constructors, or buried radials, or a combination of these. The better your earth, the better the antenna will perform. When using a resonant counterpoise, you really need a minimum of two radial wires as specified in the pdf for best performance. -- Just out of interest.. Is your inverted V doublet a full size antenna (>90ft)? If so, you probably dont need to build this antenna, which is intended for small gardens.”

Comment by 'Tim Taylor (M6AUK)' on 25 Sep 2011 - comment
“I used to use a G7FEK, but due to quick and poor construction on my part, part of the antenna snapped, and I never bothered rebuilding it, instead opting for a quick and dirty inverted V. However, I now want to put a G7FEK back up, but in a different place which is better suited, so, the question I want to ask is, does the counterpoise _HAVE_ to run underneath the longest horizontal element? To achieve the height etc for the antenna, I would have to run the counterpoise the other way, so that it ran underneath the shorter element. Does it matter if I do this? I don't want to build it if the reality is that I'm wasting my time having the antenna configured this way.”

Comment by 'Mike, G7FEK' on 8 Sep 2011 - comment
“@G0JKZ - Hi George, well done with your build. I dont say not to earth at the feedpoint, I advise that you provide the best earth you can at the feedpoint (coax outer!) and that two counterpoise radials are just the minimum for a successful antenna. At 400W you will need a reasonably good earth and choke as RF currents are higher than at 100W. I have emailed you with more detailed recommendations. Glad you have it resonant and you're already doing well without the linear. I'm sure you will solve your issue with using the linear with ease. Personally I don't find I need an amp but I guess every little helps with the poor band conditions.”

Comment by 'George G0JKZ' on 7 Sep 2011 - comment
“Built mine and put it up... works fine in resonance and managed to work a few places normally only reached on 20m. I was impressed until I switched on my amplifier... 400w on 80m sent the whole shack hot. 40m is no problem, even at a touch a bove legal limit but 80m is an issue. I'm going to try an earth at the feedpoint, even though the instructions say not to as well as a second rf choke at the feedpoint as well as one at the entrance to the shack. Its all an experimentation game! Rx wise I cannot fault the antenna, comparable with my doublet most of the time. Just got to sort this minor annoyance and it will all be great.”

Comment by 'Mike G7FEK' on 10 Aug 2011 - comment
“Adam that is really a compromise. Glad it is working for you. Should be even better when conditions on 80 improve too.”

Comment by 'Adam' on 10 Aug 2011 - comment
“Hey Mike, so I put up your antenna the other day, and I have to say I am REALLY impressed! It's a real compromise install, I cut the vertical section to 20' and added the additional to the horizontal sections. I dangled the vertical section from the crown of the roof (overhangs the house slightly), ran the 40m leg towards one corner of the roof, and then ran the 80m leg through the attic. I didn't install any counterpoise, just to the existing ground stakes that I had already. What an antenna! I'm so excited that I can finally work 40m effectively and 80m at all. I left up the G5RVJr (for now) as well. Thanks again, really neat antenna.”

Comment by 'Jarek sq1res' on 21 Jul 2011 - comment
“I have built the antenna few days ago and I have to confirm that it performs very well. At 40m I hear a lot of DX stations that I had no chance to hear on my horizontal triangle (VK, ZL, HK, ZP). There are terrible QRM on 80m at this time (July) so I have to wait a bit for this band. I used 16 buried radials in length from 5 to 10m. I am also able to make two elevated radials (10m and 20m). I wonder whether it makes sense to use buried AND elevated radials together. By the way Mike, I am also a fan of astronomy. I have a 20cm Newtonian and I intend to build a backyard observatory (Roll-Off Roof).”

Comment by 'David Pye' on 6 Jun 2011 - comment
“Hi, Very impressed with this antenna design - it seems just what I need to my garden. I am wondering how it might respond to having legs 'bent' as I think I will struggle to get it in my garden in one piece. In order to have the vertical section away from the side of the house (where it would effectively be in an alley and unlikely to radiate efficiently), I will run it up the side of some tall conifers at one corner of the garden. But that means I would need to bend the long wires somewhat to fit things in. I could either bend the 2m 'short' leg by 90' from the direction the longer leg, so that the two legs are at a right angle. Alternatively, I could move the centre support, and thereby just bend the last few metres of the longer limb. Which would be better, do you reckon? Will provide feedback and photos once it is completed!”

Comment by 'Adam W7ATJ' on 19 May 2011 - comment
“This looks like an ideal replacement for my attic G5RV Jr, however I have one question: Does the counterpoise need to be directly underneath the horizontal elements? The best I would be able to do is run the counterpoise around the base of the house, while the antenna would be centered in the attic. Also, do the two horizontal elements necessarily need to be parallel? I think the best I would be able to do would be to put them perpendicular in an "L" configuration. Thanks a lot, this looks very interesting!”

Comment by 'Ivor G6ATJ' on 20 Mar 2011 - comment
“Built the aerial to the exact dimensions, and found that it tuned OK from 80 right down to 12, with the aid of either: 1. The auto tuner in my Kenwood TS-480SAT, or 2. a Yaesu FC-700 manual tuner. I have NO counterpoise, except for the coax braid connecting to an earth spike outside the shack, and can work almost everywhere from here on the edge of the Blackdowns (save for VK!) Could the c/poise be part of my stock-proof fence which runs parallel to, but not "directly beneath" (about 10 foot to the side) the aerial? This fence is just above ground, but does NOT raise itself at either end. 73s and tnx for a great design. ”

Comment by 'Mike, G7fek' on 7 Mar 2011 - comment
“Hi Thomas, Great that you are getting good results from the antenna. Your inverted V will be better on 40m for high angle work (inter UK / western Europe) but you might find that 40m DX could still surprise you. I will soon be publishing an update with some improvements that can be made to the antenna. Keep a look out on the website, or subscribe to the RSS feed to be kept up to date. I look forward to working you on air. Please feel free to contact me via email to arrange a sked!. All the best,   Mike, G7FEK.”

Comment by 'Thomas M6TTH' on 5 Mar 2011 - comment
“Hi Mike! I just wanted to say thank you for this excellent antenna design. It's also very well documented and I had no problem constructing it in an afternoon! Since I got licenced I only had a dual 40m+20m inverted V up a tree, and no coverage of 80m. Today I am discovering this exciting band and all thanks to your compact antenna. I'll post pictures and more results when I've had some more time with the antenna, but for now it is up and working. Seems a bit weaker than my 40m full size inverted V (which is mounted lower), but on 80m it is giving amazing results so far. I'm still learning about antenna theory and design but your page has been very enlightening. PS. I passed my intermediate exam last Tuesday but haven't obtained a 2E0 call yet. Thanks and 73, Thomas M6TTH”

Comment by 'Scott' on 24 Feb 2011 - comment
“106 Countries now worked on 80m using the G7FEK. The latest countries being VP8ORK and S9DX. It just keeps working!!”

Comment by 'Tim M6AUK' on 13 Feb 2011 - comment
“I of course meant 17m and 15m! I was thinking 18Mhz at the time of writing. Apologies for any confusion :-)”

Comment by 'Mike G7FEK' on 13/02/11 - comment
“@M6AUK - Hi Tim, Great to see the antenna is working well for you and thanks for your kind comments. As the elements have some gain and low angle on the higher bands I don't recommend that you modify the antenna for ATU less operation on all bands unless you know what you are doing. The perfect match is usually a compromise of resistive or earth loss added to radiation resistance, change of radiation angle etc. Some commercial antennas take advantage of compromises by giving you a 1:1 SWR figure at 50 ohm with little regard for actual antenna performance. It is this low SWR that they know the unknowing will fall in love with. But remember that the dummy load is the ultimate example of 100% loss vs. 0% radiation efficiency but is still a 1:1 SWR. So my advice is learn more about antenna resonance, efficiency and SWR and how they are NOT the same, before modifying the antenna for lowest SWR. Don;t be misled into believing that ATUs are somehow evil. They cannot improve a poor antenna, it;s true, but for some reason, many newcomers are misled by an unfounded view that ATUs are only to fool your radio, and that if you need one then your antenna is somehow crap. This is a mistaken view and based on a lack of understanding of what impedance, SWR and radiation efficiency are. It is unfortunate that today, even those that teach the subject often do not understand it properly. ATUs have an important place in efficient impedance matching especially when working multi band. No single amateur multiband antenna resonates with an exact 50 ohm feed-point on all amateur bands it's impossible to achieve without voodoo, alchemy or extremely complex and lossy matching networks! but not being exactly 50 ohm resistive, doesn't mean they are not resonant on those bands, or they are not efficient radiators. It's far better to transfer over 99% of your power efficiently to your radiator with your ATU in line, than to be disappointed by trying to compromise the antenna to create the perfect 50 ohm match on all bands.”

Comment by 'Tim M6AUK' on 13/02/11 - comment
“Put this antenna up after using a real hash up of a doublet and getting very frustrated with the poor performance of it. This morning I had two 5/9's into Tunisia and then Nigeria, on 17m and 18m respectively, and that was before tuning the antenna! It is really working well for me so far, but I can't seem to get some of the higher bands without use of a tuner. Going to add a 17m and 18m 'element' off the horizontal so I have a fully tuned range of bands to work. Will be tweaking the whole arrangement over time, but first thoughts are that this is an exceptionally good antenna. Thanks!”

Comment by 'Scott VE3SCP' on 08/01/11 - comment
“Mission Complete! Just a quick update to the list that I have completed DXCC on 80m using the G7FEK antenna with 100 watts. Country 100 was RW2A on December 22, 2010. Since then I have added 2 more countries on 80m. My 80m distance record so far is New Zealand also worked in December. I have found that if I can hear them - I can work them. Some patience may be required though to let the higher power stations clear off first. Happy New Year to all and good DX.”

Comment by 'Mike, G7FEK' on 03/09/10 - comment
“Thanks David. Several people have reported a useful resonance on parts of lower 10m band or on 11m depending on their installation arrangements. Mine has 1:1 SWR at 27.6MHz. This does not show in the computer models but does in real life. It's a bit unpredictable where it lands. Usually somewhere above 27.5 MHz. I'm sure with a little study, the dimensions could be finely tuned so that it is repeatable and 10m become a seventh band for the antenna. For me though I find that 10m is better served from an old CB half wave antenna up in the air - and lets face it, it's easy to fit that into a small garden!”

Comment by 'David (KR4OW)' on 01/09/10 - comment
“Well I come across this antenna and the antenna building sucker that I am I had to put one up. took about 45 min with the radials (10) of them 65' long hung it off of my tilt over 4x4 post with a 2x4 at the top its is just about 28 feet. stuck the mfj259 to it and was impressed at the first shot I did not have to shorten or lengthen the wires at all I always add a little just to be safe. With just 100w and my K2 I worked 8 europeans 2 russians and 1 JA in the morning. on 80M. On 40m I worked a bunch of Europeans as well. Some with only 10 watts. Bandwith is what would be expected with this antenna. Nested dual band antenna Great! The only odd thing is that the swr curve on 10 meters is WOW! under a 1.5 I do not have it near my 10 meter vertical which is about 150' away up 60 feet. 15Meters swr was ok. 1.9 Next figure how to deploy as portable. I have enough Ladder line for 1 more I am familiar with inverted L type antennas My 160 is up at 70' But Great antenna. I wonder if I buld another I wonder if thier would be a way to phase the 2 together with dual phasing schemes Interesting thought. Any suggestions?”

Comment by 'Mike, G7FEK' on 01/07/10 - comment
“Hi Howard, I don't recommend putting 24ft of twin up a 16ft pole unless you extend the pole to 24ft. The antenna works best at 24ft vertical height. For stealth version you can use two individual wires instead of twin. You can space the wires much further apart than the standard width of twin to make a stable antenna. The actual spacing is not critical because it is not used as balanced feeder, but it should be more than 20mm. Scaling this antenna for 40m and up is possible by halving all the dimensions, but at just 12ft height, the antenna would not be fantastic. This antenna was designed with a specific purpose, to fit 80m and up into a small space!!.”

Comment by 'Howard Hornsby' on 30/06/10 - comment
“Mike, Wondering if a scaled 40-10 doable? Comments/suggestions 4 stealth version? Can go 16' above roof of mobile. I'll try weaving a home brew open wire line (full 24') up 16' mast. Thanks, Howard ”

Comment by 'mario G8ODE' on 23/02/10 - comment
“Have look at the study I did for the G7FEK on the Royal Sigs ARS web site I was sceptical so modelled the antenna using MMANA-GAL, built it, then measured the SWR and compared the results with the model. Does every thing it says on the tin! I spoke with Mike G7FEK and asked it I could publish the study on the RSARS web site. We have even had a QSO using our G7FEK antennas. I still use mine and have now taken the G5RV down as it worked so well. http://www.rsars.org.uk/ELIBRARY/docsants.htm”

Comment by 'G0BAK Leeds' on 28/01/10 - comment
“Just a quick note to say I threw up your antenna last Sunday in about 25 mins. I am delighted with it and cannot believe how well it is performing. As yet I have not tuned the legs for 80 and 40 and it is dipping lower than the said bands so I need to reduce it. I have the antenna very low and I have found the following: I am now working more stations outside the UK but still in europe on 80 metres with it. I chose your antenna as I have treat myself to a Yaesu FT950 for Christmas and I needed 50 ohm coax to the radio. I have been restricted to 80 metres, my favourite band. I have been using a lw into my garage tuned up with atu and counterpoise and then coax to the rig. this was ok but evertime I needed to change band or indeed move up to the phone section, it was a trip to the garage. I work mainly cw 5 watts qrp. I did not expect good results on the Fists Ladder yesterday but I was very pleased and used 40 metres to gain some points and also managed to work 2 uk stations on 80 metres. I have not heard my usual stations on 80 that I usually hear, I assume that must be the low angle radiation on 80. I hope to tune the antenna soon so I will let you know how I get on. thank you for your web site and for giving me a solution at my small garden qth. ”

Comment by 'Mike G7FEK' on 16/04/09 - comment
“Many thanks Scott for your tests and support for this antenna. The 2 way we had with you at the observatory with this antenna at both ends just blew me away - Brilliant.”

Comment by 'Scott VE3SCP' on 30/01/09 - comment
“Upon doing some research on the internet, I came across your article on building a quad band Marconi antenna. I modified my half size G5RV to make this antenna. I started off with only 1 radial with a length of 62 feet but I raised the radial 6 feet off the ground. I ran it on top of my wooden fence. I live about 60 miles NW of Toronto, Ontario. My QTH is about 1560 feet ASL with a low noise floor. My first contact was G0EVY on 80m and he gave me a 59 report. I was impressed already. My second contact on 80m was to Cuba, again another good haul. I heard but did attempt to work due to a huge pile up a station from Denmark with a 58 to 59 signal 2 nights ago on 80m. Thanks for your response to my e-mails, I really appreciate it. I will update you on any significant results I come up with for your records. One test I did which should impress you is with another ham located 10 miles from me. He has a half wave 80m dipole supported 135 feet up in the air. Optimum height for low angle radiation. We compared both S meter and audio tests with this station in Denmark. His S meter indicated a 59 signal and my meter indicated an 58 signal on your antenna. He was floored how well I heard this station. On a side note, it works really well at monitoring the LF NDB beacons between 150kHz and 500kHz. With your antenna I have logged over 100 low power NDB's from as far as 1600 miles away in the last 3 nights. I love antenna design and I am intrigued by this one. For a limited space antenna, this is by far the best I have used.”