![]() ![]() 6 elements was chosen, as the boom length is 2m (6.5ft) which keeps it portable, whilst still having good gain. The next problem was how to build it so it can be put together quickly. After a lot of thinking, I decided to use wooden clothes pegs to mount the elements and driven element. Magnetic Loop Antenna Calculator Spreadsheet, Slim Jim Antenna Calculator by M0NWK. Bandwidth is much narrower than a centre fed dipole due to the tuned matching section, which makes building the antenna more critical. To make the best use of an End-Fed antenna, it should be fed with a. To bring the resonant frequency down, lengthen the 1/4 wave stub. To bring the resonant frequency up, shortern the 1/4 wave stub. The challenge for this antenna was that it had to be compact enough to walk up a mountain and be very quick and easy to assemble and disassemble. Tuning can be done by adjusting the 1/4 wave stub length and the feedpoint position. It has gone through a few revisions over the years (this is version 4) and is now a 6 element Yagi Uda (poor Uda never seems to get a mention), based on a DK7ZB design, with a little tweaking in EZNEC. This page contains construction details on a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use. Since an old 5 element version (v1) of my antenna was shown in the July 2011 edition of RadCom, a few people have contacted me asking for some information on how it was constructed. Version 4 of the portable beam, the ‘PegTenna’!
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