G5RV verses Superloop 80

Many operators with small lots, a G5RV is what can fit for the 80 and 40 meter bands. The G5RV is 102 feet long and has a 34 foot
section of twinlead followed by coax into the shack, possibly with some sort of RF choke on the coax. The ends are typically supported by ropes up in
the trees. An 80 meter dipole would be about 134 feet long.

A tiny lot is limited in antenna potential and zoning laws prevent real towers.

RadioWorks “Superloop III” designed by Jim, W4FTU, and refined over the years, is a good alternative

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An easy-to-build general purpose receive only small wire loop antenna

As much as I like my coax loops, I am also quite satisfied with small loops made with wire or tubing. They have the same or better performance as the coax loops, but might require that you invest in a balun to help maintain directivity and avoid common-mode noise ingress from the feedline. If you need to null local noise yet still be able to listen to most skywave signals, these loops really perform.

The antennas described below bridge the gap between operating as a constant-current small loop (0.10 wavelength or less circumference), and intermediate-sized loop a bit larger than 0.17 wavelengths long in circumference.

If you are interested in building loops made entirely from coax cable you may want to check out my earlier project pages on that subject. It has many operational notes and other items of interest that pertain to small plain wire loops as well as to coax types.

The voltage balun was essential to help me fight common-mode noise and maintain directivity. If you don’t use a balun and have good results, you may not have much noise to deal with in the first place, or the skewed directional pattern has a null that works for you - even if it isn’t textbook. See my balun notes below.

I initially chose 14 feet since my noise problem extends up into the 40 meter band; I didn’t want the antenna to be longer than 1/10th wavelength because you start to lose your nulls with larger wavelengths of wire. I just did a quick calculation: (1005 / 7.150 * 0.10)

Note that I have since opted to use 28 feet overall, because I wanted better sensitivity on 160 and 80 meters, and now at 40 meters the 28 feet of wire still gives me a slight null - adequate enough for me to null my local noise on 40. Unfortunately I don’t have the room for a full-sized loop, so I had to wind it with two turns. See the EZNEC® antenna modeling plots below.

Here are some quick construction tips to get you up and running quickly. I’m still studying the antenna and will improve the page as time goes on.

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Design of my cards has finished and my new QSL card is going to be printed. I’ve been working on this card since last month, and I’ve asked some offers all around the world for printing prices. I’ve used my Apple PowerMac G4 with Adobe Photoshop and Adobe (Macromedia) Freehand to produce the final layout, that you can see here. Picture has been taken with a Canon G5 Digital Camera.

About the subject, I’ve had a large choice od themes, considering that my city host so many famous monuments and panoramas but I’ve decided to use the Ponte Vecchio, since is one of the most representative monuments in Florence, and because is not so used by local hams for their QSL cards.
As said before I’ve been asking prices to almost all world wide famous ham radio qsl printers, and finally I’ve decided for IT9EJW service, mainly for clear information contained on his web site and for his competitive prices.
A complete list of links to QSL Printers has driven me for the choice of printing service.
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On 2nd October 2006, Stefano Galastri IK5IIR, passed away.
He can be considered the european father of EH Antennas, since along to Ted Hart W5QJR was the main promoter and inventor of EH Antennas.
I’ve know personally Stefano since he was member of the local radio club here in Firenze. I’ve attended to some of his lessons on homebrewing EH antennas few years ago. Hams here say he was a gentleman and a very expert ham radio operator, he will be missed among the ham radio community. 73’s Stefano.