Another ground radial question!

[Bill, KD0HG]

Over the last week, I have been repairing a vandalized radial system under a 4-tower broadcast array. It's the customary sort of thing, 100+ radials of #10 copper under each tower.

While scraping the dirt back with a Bobcat, it became evident that in the past, someone had installed a radial ring around each of the 4 towers; about 50' out from each tower base there is a circular ring of #10 which is soldered to and electrically ties all of the radials together.

Is there any reason why this was done? I've never seen anything like this before..

Bill

[W7TFO]

Old school thought was sometimes to include another set of 50' radials interspersed, and a bonding ring at that point to the longer set.

Seen mostly in cases where high E values were expected.

73DG

[KM1H]

Done to try to improve the close in ground loss where RF current is highest and often included several connected rings every 10-15' or so.

It was seeing the latter that convinced me to lay down a 50' long carpet of 5 2"x 4" welded, galvanized and plastic dipped garden mesh at the base of a 100' shunt fed tower with 100 radials that wasnt getting out as expected. The mesh made a huge difference but all the work involved convinced me to go with elevated radials when I moved here.

Carl

[k4kyv]

Although written primarily with buried copper and copper alloy piping systems in mind, this should apply equally well to buried radials, ground wires, copper clad ground rods, etc.

Note that soils with the best ground conductivity (resistivity below 100 to 500 ohm-cm) may be the most corrosive to buried copper.

Preventing corrosion of buried copper

[KM1H]

During the Beverage rebuilds the past 2 years I relocated several 8' copper clad utility grade ground rods that were driven in at shallow angles due to the solid rock only 2' or so down. It came out nice and shiny after 20-22 years in the mix of pine and hardwood forest.