On 7/27/2024 12:47 PM, jim.thom jim.t...@telus.net wrote:
Has anyone had success with a 160m, 1/4 wave sloper....hanging off a 90' tower, with a 40m yagi just above the top of the tower ?
Yes, I've successfully used a sloping wire, suspended from a piece of large PVC conduit running horizontally through the tower at the top. I feed it against radials at the bottom, about 20 ft off the ground. N6BT, who has done a lot with verticals and elevated radials on 160, told me that they need to be near that height for reasonable efficiency. I've also added a dozen or so on-ground radials to the tower, which causes in to act as a passive reflector, yielding a few dB gain in the direction of the slope.
An important piece of advice -- if your sloper is shorter than a quarter wave, do NOT add a loading coil, just feed it with a decent RG-213/RG8 size coax and tune it in the shack. Loss is quite low in that size coax on 160, but the feedpoint is a high current point, which makes it an important part of the antenna; a loading coil at that point eliminates part of the high-current, making the antenna a bit less efficient.
73, Jim K9YC _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
