I have posted this link before. This gives the background on why buried Log or Bog antennas don’t perform well. Figure 39 is worth looking at:
https://rudys.typepad.com/files/qexjul-aug-2016-bog.pdfThis should be no surprise if you think about the difference in performance of buried vs elevated radials on a vertical antenna. Verticals only need a few radials if the radials are elevated above ground, but they do need to be the right length. Buried radials require many of them to achieve similar performance but the specific length of them tends to be less critical as ground losses become more dominant.
A few years ago I put up (down?) a 1000 ft BoG for the winter DX season. I used a roll of cheap outside rated CAT5 UTP cable I bought off of Amazon. This cable was 24 ga copper clad aluminum (CCA) wire. I twisted all the wires together at each end and fed it with a 9:1 (I think) balun. The resistance of each of the individual wires was about 75 ohms, so it was probably about 9 ohms for the entire length of the antenna. An external preamp was not used.
I was pleased with how well it worked for LW NDB DXing. Part way through the season performance seemed to drop off a little, but I attributed that to conditions. I was still hearing many new stations.
When I rolled it up in the Spring I found that I actually had 4 pieces of wire. Some time during the Winter a rabbit or squirrel had chewed through the wire at multiple spots. My LoG had become a large OCF-dipole-on-the-ground!
One of my original reasons for measuring the wire resistance had been for future troubleshooting, but during the course of the season I never rechecked it. If I had it would have become obvious that the wire had been severed.
I will probably install another LoG this Fall. I may use copper wire this time but I really don’t expect a noticeable difference over CCA. Receive antenna currents are extremely small and (I squared R) losses aren’t very large. People build Beverage antennas using aluminum or Copperweld fence wire all the time. W8JI had some comments on wire types for Beverage antennas, but he said the biggest reasons to choose one over the other were largely focused on how well the wire survived environmental conditions and how difficult it was to work with.
http://www.w8ji.com/beverages.htmThere is probably a sweet spot regarding the minimum length of a LoG. Too little wire won’t capture enough signal. KK5JY suggests 15% of the target wavelength.
http://www.kk5jy.net/LoG/My tests this Winter may use a roll of Home Depot THNN copper house wire (about 500 ft) instead of the 1000 ft CAT5 UTP as I want to see if this length will be useful at LF.
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