RadCom April 2024, Vol. 100, No. 4
April 2024 51 Review that there was a step-by-step assembly guide. There’s lots of great information in the User Guide, but it’s easy to miss bits and only discover later that you must go back and re- do something. I was keen to get some elements onto the pole. The User Guide gives a cutting chart. The idea is that you cut each element exactly to the length specified. On most bands, you’ll need to create what is called a ‘fold-back loop’. Simply loop the wire back on itself, twist it together and tape the loop back to the main element. Once you’re happy that everything tunes as it should, you can replace the tape with heat-shrink tubing to secure it. Cut the element to the lengths specified and you’ll need to fit a fork connector to the end and crimp it. The instructions give reassurance that, if you don’t have a crimping tool, an old blunt pair of side cutters will suffice. Once it’s crimped on, fit some heat-shrink tubing over the fork connector to prevent the ingress of water. In all cases, you’ll need to use a bit of shock cord (supplied) to go from the loop in the end of the element you’ve created up to the next spreader on the pole. See Callum’s video if you’re not confident with knots. Getting the right tension takes a little experimentation. Initially, I over-tensioned one of the elements and a few minutes later heard a noise like an electrical trip going off. After that, I probably under-tensioned a couple of elements, but this is quite easily adjusted. Do label your elements; it makes debugging any issues a little simpler. Callum suggests multi-coloured tape or beads. I kept creating the elements and adding them onto the pole – quite a satisfying process. It was starting to look good. Bear in mind that the 40m element goes all the way up to the top of the pole and back down the other side to a spot around 2/3 of the way up the pole. This gives you both a quarter wave length on 40m, as well as something around a 5/8 wavelength on 15m. I was a little nervous about how the tuning would work out, but hoped for the best and carried on. I did miss the instruction to create a tensioning loop on both the 30m and 40m elements to keep the elements nice and tight. Fortunately, this wasn’t a problem; I simply went back and added a little loop to both elements, and created a tensioning section from the shock cord. After a couple of hours of measuring, cutting, crimping and knotting, all the elements were on the pole. Next, it was time to make some radials. Callum says that he gets more questions about radials than anything else. The instructions are quite clear that, as long as you have some radials, then the antenna will work, but it is better to have more radials. Do make your antenna elements first and your radials later, to ensure you have enough wire; two 100m rolls of wire are supplied, so you should have plenty. The instructions continue: “After making your elements, and with the spare wire, make up your radials according to any length that fits your location. This means some can be smaller and some can be longer. It really doesn’t matter.” It’s suggested that you have four radials on each fork connector. As a starting point, based on the space available around the base that I had built, I decided to go for 4m long radials and have 4 sets of 4 radials. That kept me busy for another hour or so, as I cut, crimped and heat-shrunk the fork/radial connections. With all this done, it was time to get the antenna up and try it out. Don’t forget to place the ground plate over the ground post first, with the SO-239 connector installed in the ground plate. Carrying the antenna up to its location, I was amazed by how light it was. Lifting it up to vertical was quite easy on my own, although there was a light gale blowing, so getting the base of the pole to slip over the ground post took a few seconds longer than I’d have liked. Then, it was a case of attaching the radials and spreading them out in a reasonably uniform fashion around the base of the antenna and, finally, attaching the coaxial cable back to the shack. Time to try it out Excited but a little nervous, I went up to the shack and was reassured that band noise sounded encouraging. A quick transmission on all the bands between 10 and 40m showed that VSWR was perfectly acceptable on all bands. Wow! Well done DX Commander and well done me. Not being the best at following instructions, I was relieved. My first test was a 100W CW CQ on 28MHz. Admittedly, the band was quite nicely open, but the Reverse Beacon Network showed my signal being heard in Hong Kong and China amongst other places. Over the next few days, I was like a Tim Kirby, GW4VXE gw4vxe@icloud.com FIGURE 2: Installing the ground post.
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