2016-12-05

Antenna for 30 - 80m

The weather has been cool to cold, but a milder spell made it possible to set up a simple antenna for the lower bands.

The antenna consists in a vertical part about 15m long, a telescopic fiberglass with a wire attached, supported inside the branches of a tree, and a few horizontal wires as "radials".

Right now I have 2 wires one is about 5.5m and one about 25m long. at the feedpoint has a 9:1 UN-UN (transformer). The wire lengths are intended to have the feed point at approximately 1/3 wavelengths on 80 resp. 40m. Not perfect, but workable. The tuner built into the IC-7600 tunes at 30, 40, 60 and 80. The high end of 160m is difficult, but it *does* tune.

At a later stage I expect to have some DC power  fed to a tuner at the feedpoint, and get some real radials into the ground (and possibly a few above ground, but the winter weather will probably make me wait until spring to do that. I would expect better results from that combination, but for now, since last night I have worked a bit of DX on 30m and signals are pretty good on 80m and 40m, for local (European) signals it is nicely comparable to my dipole, but for DX more tests are needed. I do not expect miracles, but some DX should be possible on the low bands now.

The vertical part is placed in between the branches of a few trees, so the antenna is fairly unobtrusive, though not really invisible. It will only be noticed if you know what to look for.

Update :

A fault was corrected in the system, resulting in a sufficiently low SWR on all bands 80 - 10m not needing the tuner, and the SWR on 160m being less than 2.5, making it tunable with the built-in tuner of the IC-7300. Very nice. 

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