This is essentially an upgrade of project 7
Airband Dipole . I thought the results from that roughly built, simple,"thrown together" Dipole were encouraging enough to build something more permanent. Once again, the materials were cheap : a 3 way junction box, 1 metre length of aluminium tubing, 8 cm of old nylex garden hose and silicon sealant.
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Hose sections used as packing |
The tubing came as 1 m length so i cut that in half. The tubing does not fit snugly into the "T-piece" so some packing is required. In this case, 2 bits of old garden hose cut into 4 cm sections and then cut down the middle, opened up and pushed onto the tubing which then fits nicely into the box. The bits of excess hose are then trimmed off.
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Packing trimmed and holed drilled |
After that, the holes are drilled for the coax fittings. The standard nuts, bolts, washers and auto-electric crimped type connectors are used. The box cover plate is screwed back on, and silicon sealant is applied just about everywhere.
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co-ax fitted |
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cover replaced |
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mounted |
Once that had cured, it was mounted in place of my weather station which despite being guaranteed to be made of U.V. resistant plastic, is falling to pieces after 5 years in the aussie sun. This time the antenna is mounted a wave length away from the mast which i noticed is the practice used on commercial VHF antennas.
Unsurprisingly, this gem of an antenna performs far better than its predecessor. I have really enjoyed the progress of these 2 builds. It started as in idea i saw on the web, then to a rough prototype for proof of concept and now the final build. A very simple, top performing antenna build, enjoyable from start to finish.