Topband: Historical note: Radial Depth

[Donald Chester]

I was looking through my old ARRL Antenna Books.  The text in the "Antennas for 160m" chapter in the 1939, 1944 and 1949 issues in my collection state: "The ideal form of ground is a series of conductors buried A FOOT OR TWO beneath the surface, radiating like the  spokes of a wheel from under the vertical part of the antenna, as shown in (the drawing).  Its construction is beyond most amateurs, but it is mentioned here for the benefit of those who may have the space and a plough to cut the furrows which contain the ground conductors."
A drawing on the next page illustrates radials buried indeed a foot or two below the surface. See pages 92-93 in the 1944 edition.  

At first I thought this had to be a misprint, but upon further investigation I see that this is repeated verbatim year after year for at least a decade.  The 1974 edition recommends a more realistic depth of two to four INCHES.  I couldn't imagine anyone digging all those trenches  to bury radial wire 1 to 2 feet in the ground, and agreed this construction would be beyond most amateurs, but neither can I imagine that someone writing for a respected technical publication would have recommended such a thing in the first place, and that it would have gone uncorrected for a decade or more. I wonder how many hams of that era were discouraged from using a radial system because of this misinformation.

Beside the arduous and unnecessary work to dig the trenches, the effectiveness of the ground plane is compromised with that much lossy earth between the vertical radiator and the radial ground plane.

Don k4kyv