My last post about the multiband halo was a bit depressing. I miss the antenna because when it worked I was very content with it. It might not be the ultimate DX antenna and hasn't much gain. But it receives well and it is almost omni directional. I decided to make a rebuild and solve the issues that occurred in the last 2 years. Luckily I've written some experiences in this blog that are now very useful.
Viewing the pic at the left. I fixed the "hanging" poles by uv resistant guy wires. Instead of using speakerwire, twinlead or ladderline I decided to go for a real halo design. Just to see what difference will occur. From publications I've read so far it is best to start with the highest frequency halo. In my case this will be the 12m (24MHz) halo.
Unfortunately the weather is getting worse these days. And I'm not having that much time. I've made the "core" of the antenna stronger and made all the necessary plastic items like distance holders last week after my work in the evening just before sunset. It gives me about an hour a day. This sunday I had big plans but when inspecting the house gutters I also found some other loose roof parts that had to be repaired before winter. Of course that was much more important. My intention was to get the antenna working before the CQWW next weekend but this will probably not happen. It doesn't matter much because I probably do a 10m single band effort again.
I wanted at least the 12m band halo be ready today. Luckily I had enough time for that at daylight. Above you see part of the construction. Wires are spaced about 4cm. The ends are tied into a point. It is a choice. It can also be flat ended. This was easier for me. When flat ended there will be more capacity between the ends in the end that will make tuning more difficult.
I already discovered a interesting feature. When I first measured the SWR/resonance the loop was a bit too large. Resonating on about 24.8 MHz. Bending wires back did not do the trick much. But shifting the plastic spacers back to form a sharper point brought the resonance up quickly to 24,9 MHz
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