If you’ve ever cast your eye towards the rooftops, you’ll be familiar with the Yagi antenna. A dipole radiator with a reflector and a series of passive director elements in front of it, you’ll find them in all fields of radio including in a lot of cases the TV antenna on your rooftop.
In the world of amateur radio they are used extensively, both in fixed and portable situations. One of their most portable uses comes from the amateur satellite community, who at the most basic level use handheld Yagi antennas to manually track passing satellites. As you can imagine, holding up an antenna for the pass of a satellite can be a test for your muscles, so a lot of effort has gone into making Yagis for this application that are as lightweight as possible.
[Tysonpower] has a contribution to the world of lightweight Yagis, he’s taken a conventional design with a PVC boom and updated it with a stronger and lighter boom made from carbon fibre composite pipe. The elements are copper-coated steel welding rods, some inexpensive aluminium clamps came from AliExpress, and all is held together by some 3D-printed parts. As a result the whole unit comes in at a claimed bargain price of under 20 Euros.
This antenna is for the 2 M (144 MHz) amateur band, but since it’s based on the [WB0CMT] “7 dB for 7 bucks” (PDF) design it should be easily modified for other frequencies. The 3D printed parts can be found on Thingiverse, and he’s also posted a couple of videos in German. We’ve posted the one showing the build below the break, you can find the other showing the antenna being tested at the link above.
We’ve featured a few Yagi builds here in the past, like this one using metal tape measures as elements, and another using aluminium arrow shafts.
Filed under: radio hacks
via radio hacks – Hackaday http://ift.tt/2krt1mt
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