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This past Sunday I took my new homebrew 20m Delta Loop out for a spin and tuning, but forgot to bring my supplies to cut and solder so I just used a tuner. That wasn't the tough part. The tough part was trying to deploy it without tangling itself up or being lopsided. Any good tips on how to best deploy it when I'm using it?
I made it so it could be set up either apex up or down and the feed point in the apex, middle or corner with sliding acrylic tie-offs. When I first put it up on Sunday, I did it with the feed point in the middle of the bottom flat and the apex at the highest point (about 25' high). I had to raise and lower it a few times because it kept spinning and tangling itself, making it hard to get good separation at the top. I finally got it right but realized that one leg was shorter than it was supposed to be and put the feed point to one side. Not a big deal really, but my OCD needed it to be where I wanted it so up and down the top went until I had it even. It worked amazingly well and I was very proud of myself for making it. But the not-so-easy deployment had me thinking if there was a better way?
I thought about putting loops at the corners and the apex, but that would defeat the versatility of being able to deploy it with apex up or down, and also having the feed point in different spots along its leg. I also thought about making removeable tie-offs so I could use them when needed but take them off when not needed, or even modify them so I can lessen any twisting or tangles at the apex. What has your collective experiences been with these antennas? Is one configuration better than another? I'm curious about this as from what I've read it can be a really handy antenna.
I have never tried a delta loop, but I do use wire antennas a lot for portable operating. I suspect some deployment challenges and successes are directly applicable, but others may not translate well. So, a few thoughts...
1. A lot depends on how you plan to support your loop. Using a mast in an open field would be a lot easier than using a throw line in dense woods. Low branches and under-story saplings can make it very difficult to get a desired configuration, even with a single wire. Open, old-growth forest is wonderful for deploying antennas, but is often unavailable.
2. Supporting an antenna from multiple elevated points adds greatly to complexity. Dipoles, EFHWs, and EFRWs are much easier to deploy as inverted Vees (or slopers) than as flat-tops. I suspect the same will be true for your delta loop (i.e., much easier to deploy with apex up).
3. I mostly rely on a throwline over a tree branch to support my antenna. Tying a loop around the antenna wire let's me pull it up with the throw line, and also lets me slide the wire back and forth to optimize configuration. Supporting your delta with a loop at each corner could let you slide the loop to position your feed point. I try not to pull my wire over tree branches, because it helps me avoid getting the wire snagged.
4. I carry several pieces of thin, braided nylon cord to enable me to secure the lower ends of my wires. This would likely work well for your loop. Carrying one or two plastic tent stakes lets you place an anchor point anywhere, if trees or bushes are not conveniently located.
5. When deploying a wire as an inverted Vee, I first throw my line over a convenient branch. Next, I stretch out the wire to approximately locate the ends. I tie the ends odd approximately, then hoist up the apex. Final step is to adjust position and tension of the ends (also attaching the feedline). If I were to deploy a delta loop, I would try to pull up the apex first, then rig out the lower corners.
Hopefully some of this makes sense, and perhaps even helpful. Good luck, and have fun!
