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VK5ZVS |
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| 2 metre folded dipole |
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| This antenna was a re-incarnation of a version I had 15+ years ago. That one had aluminium tubing. This one is all copper. So much more convenient - the bits can
be soft soldered and re-aligned easily. The final cable termination is soldered directly onto the 1/4 wave sections. I used RG-213 and made a 4to1 coaxial balun. This antenna requires an insulated
boom and supports. I used 40mm pvc electrical conduit for the main boom and 20 or 25 mm pvc conduit for the top and bottom supports. Final assembly was done by placing copper elements in place and
soft soldering the elbows with rosin cored solder. The supports are the only items that have screws going through them and the boom. I only used two 50mm brass bolts, washers and hex nuts. Simple.
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| Yes. This is the other side. The placement of the 4 to 1 balun does not appear to affect either the
performance of the antenna nor the vswr. Plastic cable ties are used to secure cable and balun and to stop any movement in the wind.
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| Here's a pic of the original 15+ year old antenna. The pvc tubing is 40mm ex-telecom type conduit(white).
The bolts are rusty steel. The elements were made from aluminium tubing. The ends were peened over with a piece of aluminium
phasing harness put in the tube ends to make the bended sections (for electrical continuity). The 4:1 coaxial balun was then screwed
via self tapping screws to the aluminium sections. It still tuned up but was starting to weaken from corrosion and required too
regular maintenance.
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| This is the 70cm version of the same antenna - only much smaller! The conduit is 25mm and 20mm pvc. I used a rivet on either side
of the boom to secure each support arm. No point wasting bolts! Simply elegant.
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