Central Vermont (my QTH) has just about the worst conductivity soil in the
US. Glacial till on top of Granite. One of the US?s largest and oldest
Granite mines is only 5 miles from my QTH and is visible across the valley
when I am on the tower. Having lived in W5 (Houston area), I know how
wonderful packed clay can be for good conductivity.
I have a 2 el T top phased array (70 ft vertical elements). Each has about
50 radials on the ground. 75% are ¼ wave and the balance are the length
they could be given the terrain and obstructions.
I used the method of continuing to lay radials as long as the last 4 ? 8
radials reduced the input impedance to closer to ideal. If the measurement
doesn?t change much after laying 4 ? 8 radials, you are reaching diminishing
returns. The difference between 8 radials and 32 radials is inspiring
enough to keep laying radials.
They work well. How much better would they work with Clay conductivity out
5 wavelengths? No idea. They do not work as well as W1KM Salt March that?s
for sure.
I cannot comment on the HiZ receive array. But I have long, terminated
beverages that work very well and are known performers for poor conductivity
soil if you have the room.
73
Ed N1UR
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