During the summer I finished off my Cobwebb antenna. It was an antenna build that wasn’t exactly testing the idea for me was that it was portable and easy to assemble and take down when I was away on travels for holidays and such like. I used some fairly heavy gauge figure of 8 wire (speaker cable) and found that the resonance was slightly off where I wanted it to be and consequently after a lot of tuning managed a compromise.
Two things have caused a bit of heartache with this antenna (I think heartache may be a bit strong but they were annoying enough to make me want to look at it again) were; firstly, the weight of the thing hardly made me want to hump it up a fell and when out and about on SOTA and WOTA activations I reached for the lighter weight (but poorer performing) miracle whip whenever I was planning on an HF activation. The other bee in my bonnet was that it was a bit of a hassle to assemble as there was wire everywhere that didn’t form a nice shape round the antenna. Not a performance issue but it took a while to ‘organise’ it.
I came across an article on G3TXQ’s website which moved the chokes to the centre feed point and did away with the need for figure of 8 cable and a tapping point. So I’ve ordered a couple of ft140-61 toroid’s from AMTools on eBay and time permitting will be putting together a single wire Cobwebb to make a comparison over the Christmas holidays.
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