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Spurred by the good performance from my omni-directional verticals and specially the bidirectional half-square I could not stop pondering on a beam version of the latter. The half-square had proven to be a very nice companion. One should not look … Continue reading
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There’s more to antennas than meet the eye. Every antenna type has its own typical performance. One can fathom antennas by their radiation pattern. This pattern can be divided into mainly two categories. And the radiation pattern is governed not only … Continue reading
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When we say vertical antennas we normally mean a quarterwave monopole stick, or ground plane antenna. While the ground plane antenna has many virtues it relies heavily on a good ground for its performance. A good ground system often means laying out … Continue reading
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The VHD turned out to be a great antenna. The low angle radiation really makes the difference sometimes. A mixed blessing is that the radiation pattern seen from above is omnidirectional. Hmmm… In the same way as two element beams … Continue reading
Having experienced my vertical dipole on the bands and having improved it with a parasitic reflector I decided to make the reflector a director also. I knew this meant making the parasitic element shorter than it was. My plan was … Continue reading
My experiments with verticals go on. I recently built a half-square antenna and found it both simple to get up and running as well as efficient. In fact given a choice I would go for a half-square most of the … Continue reading
Over the years I have grown quite fond of vertical antennas. They have several nice properties not least the small estate required and the low take-off angle which makes them useful for DX. The bare vertical antenna (e.g. a quarter … Continue reading
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It is the current in the antenna wire that creates the radiation. A larger current means higher radiation and so increased signal strength at the receiver. And a larger current can be acheived with final amplifiers. This is however costly. … Continue reading
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This is an intriguing antenna. Compared to a full-size 2 element yagi it is much smaller, yet gives comparable performance. This sounds great for shortwave, where antennas often get too large to be easily manageable. I decided to make a … Continue reading
Note: This is not all my own work. AA2NN has described the direction switching Moxon earlier. But the sensitivity analysis is mine and in anyway the idea of a loaded, tuneable reflector seems to have disappeared nowadays and may need … Continue reading
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