Spring contest season demanded a new antenna that would handle 160m with some efficiency and compliment my other antennas. I settled on the >1 wavelength horizontal loop for its multi-band potential, relative invisibility, and ease of matching. Anything over a wavelength on 160m (540′ length) would be sufficient, but longer is better, as it lowers radiation angles and improves performance.
I already had an 80m dipole of 18 gauge magnet wire across and above the front of the house and through the trees, low enough to be considered NVIS, fed with TV twin lead and an autotuner. It was fine, but never outdid either of my two best antennas, a 20/40/80m fan dipole with feed point near 60′ and ends above 20′, and an old tribander driven element (Cushcraft A3, 10-15-20m) pulled up vertically with the feed point at least 60′ up. I decided I could use it as the starting point for a really big loop, and bought a 500′ roll of 14 gauge THHN house wire at the local big box builder’s supply. I already had another roll with at least 300′ still on it at home, and was envisioning at least a 900′ loop (120′ + 500′ + 300′) high in the trees in the woods around my house, using the old 80m stealth dipole to limit visibility from the street and so I didn’t have to fuss with a new feed line/feed point setup.
Using my trusty casting rod (loaded with fresh, 30 pound test, teflon-coated braided Spiderwire fishing line) and a one ounce sinker painted blaze orange, and equipped with several hundred-foot hanks of slippery 1/4″ nylon rope, I ventured into the woods … again, and again, and again. Almost every afternoon after work I would head out into the woods, cast the sinker over a tree top, jiggle and tug on the line until the sinker came down to ground, and, once the line was where I wanted, tie the rope to the line and reel it over the tree. Then I would tug on the rope to do some more positioning, getting it over and around the more troublesome low branches, and then use it to pull the end of the wire through the same path. I had the roll of wire on the back patio, suspended on a 20″ rod inside a lid-less cardboard box so it would pay the wire out when I pulled on the other end.
Sometimes I had to cut the sinker off, reel the line back, and try again … many times actually. I worked hard at not getting frustrated. I was sometimes showered with dead twigs, and on a few occasions had to break the line, leaving an orange sinker swinging in the breeze far above. After the first few trees it was getting pretty hard to pull the wire, so I put one of the hundred-foot hanks of rope over the wire in a loop and tied the two ends to a very small sapling – this would allow me to pull the wire down to the ground and pull it one way or the other when needed, but allow it to be pulled up as high as 50′ into the trees without losing the ability to get to it.
After pulling the wire through about 6 trees in a big arc I was now a couple of hundred feet behind the house in a land-locked, city-owned woods with no paths through it. Since I was doing all this before the leaves came out (purposefully!) I could be seen from a number of nearby houses, and I kept wondering when I would be approached (hopefully not by a city official) by someone asking what in the heck I was doing. Finally, it happened. As I was wandering around trying to spot where the line and sinker had come down, a man walked toward me from one of the houses. I walked towards him and said hello, introduced myself, shook his hand, and he asked what I was about. I explained honestly where I lived and what I was doing. He asked if what I was doing wasn’t going to hurt the trees, and I said it would not. I explained that I move each of my wire antennas a bit every Spring to ensure no tree grows around it, and carefully remove all of it when I decide not to use it any more. I also pointed out that it would continue to be invisible in the tree tops, and would pose no risk or problem to anyone. He asked if I had a permit to do this, and I said I had looked into the matter and found no system for permitting what I was doing. After some more terse questions, during which he only waved towards his house and never gave his name, he said pointedly “I’d rather you didn’t.” and walked off.
I was pretty angry, as I felt I had been cordial, honest, and forthcoming about what I was doing, and that it wouldn’t even be visible to him once I was done, but I also knew that if he wanted to make a stink by calling the city and stirring them up, it would just be a hassle. I would have to explain what I was doing over and over, and eventually, in lieu of other information, I would be told “No” if for no other reason than that it is easier to say no and have nothing more to worry about, as opposed to having to understand what was involved or risk someone else asking why you had said yes. I decided to route my wire the other way, away from his house and over a slight rise to where he wouldn’t see me working on the project any further.
That out of the way, I now worked my way back through several trees to the front corner of my lot, near the end of the existing 80m doublet, now pulling the wire along in stages. My cat had a great time chasing me around as I went from one spot in the woods to another, back and forth, moving the wire along 30-50 feet at a time. I had to re-cast a line over a tree at the edge of the front yard as the existing dipole was rather low. Eventually I had pulled the 14 gauge wire down into the front yard, gotten out the soldering iron, extension cord, etc., and soldered the 14 gauge wire end to the 18 gauge magnet wire of the 80m dipole. Then I pulled back some of the 14 gauge wire to raise the magnet wire and feed point back above the house.
Next I went back to the back yard and unrolled the last 100-150 feet of the spool of 14 gauge house wire, stretched it out, and prepared to get it up into the trees and around to where it could connect to the other end of the 80m dipole. This was hard, as a spot to cast from that was free from low shrubs and tree branches was hard to find. I must have made 10-15 casts, fighting line tangles in the branches and my own poor aim, until finally I had the line in a great, high spot, and was able to pull the wire through branches over 60′ up and back to the ground. I pulled the wire over the last tree and down to the driveway, where I soldered it to the other end of the 80m dipole. Note that at each of these connections I soldered a couple of inches of the wires together (probably an inch would have been sufficient, and possibly more durable), then taped it over with black tape to keep the elements away from the solder and hopefully smooth any rough spots that would hang up in tree branches. Finally I was able to pull the 14 gauge wire in the back yard and raise the dipole-feed point in the front up over the house. Everything was great except that I now had a wire hanging down to the ground in the back yard with about 25 feet lying on the ground.
I went inside the house and fired up the station. A quick tune of the autotuner at very low power and the signals were booming in on the loop, even with 125 feet of it hanging down to (and on) the ground at a point just about opposite the feed point. In comparison tests it provided incoming signal strengths just about equal to my two best antennas, and once in a while even better. On 160m it was several S-units above my 20/40/80 dipole, which was exactly what I had hoped. The next afternoon I connected the loose wire in the back yard to the rope that suspends the vertical tribander element (lowering that antenna to the ground for a quick checkup and re-rigging of the cord suspending the coaxial choke balun). The wire in the back yard soon looked like a 25′ high ‘W’, but the lowest point was at least 15 or 20 feet off the ground. It was the eve of the 2009 WPX SSB contest, and I had been thrashing for 3 weeks to get ready for it. With a huge sigh of relief I was finally there, but it was not quite yet to be.
The next morning the 18 gauge magnet wire had broken. Fortunately I was all ready to cast a line over the tree at the edge of the front yard, pull the wire back over, and re-solder it, which took well under and hour of fussing and repeated casts. The contest got under way at 8P EDT and the bands were crowded with the big guns, signal strengths were just so-so, and nobody could seemingly hear my QRP signal. I had a very frustrating hour of perhaps 7 Qs before joining my wife upstairs for a Friday night drink and eventually hitting the hay. The next day I only put in about 7 hours on the contest due to other requirements, but got my QSO count up around 50. Then Sunday morning at 5:30 I got on 80m and started to really go at it, and by the end of the contest 14.5 hours later had 219 Qs and approximately 75,000 points – an amazing performance, though my maximum QSO rate peaked at 22 in one hour – rather meager, actually. That was twice my best past QSO total and more than three times my best past score, so I was (am) elated. The big loop did very well, providing a second or third antenna for every band, and had the best signal strengths about 20% of the time – a great result.
If I could only have one antenna, and couldn’t have a tower and beam (as I can’t really now), it would definitely be a big horizontal loop. Matching it is easy across the spectrum, it’s very inexpensive and not too difficult to put up, its closed loop dissipates static and keeps at least some of the noise down, its efficiency is high, and it is virtually invisible to the neighbors. Once it’s up, it’s a great stealth antenna with excellent performance, and ideal for any city (or country) lot with trees.
I hope you get a chance to try one for yourself some time, as I know you will enjoy the big loop’s performance.
Best rx & 73 de kt8k – Tim