Following up on last week's antenna construction post It's Not Pretty, here's the finished product silhouetted against a cloudy sky. Not exactly up to HOA standards, but then I don't live under an HOA.Construction notes: 11' section of chainlink fence toprail fitted to a 4' section of PVC. The top of the PVC pipe is "castled" out for the ground plane legs, and the antenna simply rests in the end of the pipe. The coax cable runs through the PVC and through a cut-out on its side, above the joint with the steel pipe. It's tied with bank line to where the edge purlin is nailed to a roof rafter, just outside of the ham shack, so only a 25' length of coax is needed. I would have preferred to have it around back off the porch, but that would have meant a 50 or perhaps even 75 foot length of coax, and you just don't want to use something that long at 440 MHz. As it is with LMR-240 coax (pretty good stuff) over a 25' run, it's losing 26% of power in the coax. (coax loss calculator)
It's a good between-the-rain-showers project. Initial pinging of the Diamondhead repeater gets a response back that's about 6 dB better than in the back porch tests. That jibes with the Egli equation, which has gain going as antenna height squared. More later, as soon as one of the other area hams happens to be on the repeater to answer.
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