Wednesday, December 18, 2019
The bi-quad antenna
Some tyes of antennas are used in other facets of radio but don't commonly find their way into the ham world. One of those is the bi-quad. It's basically two quad loops in parallel but configured so it looks like a bow tie (vertically polarised version). They're most common for 2.4 GHz wi-fi work where they can be made from a piece of wire soldered to an antenna connector. A reflector behind gives some extra gain and directivity. If you have a little more room there is such a thing as a double bi-quad (4 squares instead of 2) for even more gain.
You can make one from wire for 70cm if you scale the dimensions up. My own quick experiments have been promising though there's far less activity here on 70cm (especially digital modes) than 2m.
Anyway here's some links to follow up if you're interested.
PS: Find hints and tips for working DX in Minimum QRP. It's the top-selling manual on the equipment, antennas, operating and strategy of successful QRP operating. And its techniques work for 100 watts as well. It's available for under $US 5 each in electronic form. Or you can get a paperback version. Visit VK3YE Radio Books to find out more.
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