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## Re: Topband: Optimal radial wire type and gauge?

 To: "DAVID CUTHBERT" , "Rick Kiessig" Re: Topband: Optimal radial wire type and gauge? "Tom W8JI" Tom W8JI Sat, 15 Dec 2012 19:10:09 -0500 mailto:topband@contesting.com>
 There is no magic about 120 radials, and long before 120 radials are reached the increase in field strength pretty much stops. ``` ```At my house around 30 radials or so, about 1/4 wave long, go flat on efficiency increase on 160 meters. ``` ```I could have a million radials and it would be insignificantly different than 30 radials when they are 1/4 wave long here. ``` ```I found this by measuring field strength, and I also found feed resistance change did NOT necessarily track the field strength changes. Good luck on using base impedance to determine effiency changes! In a 40 meter test, for example, one ground system provided 35-40 ohms of feed resistance and another different system that provided almost 60 ohms of feedpoint resistance had equal field strength. ``` I think N6RK and others have measured the same. 73 Tom ```----- Original Message ----- From: "DAVID CUTHBERT" ```To: "Rick Kiessig" Cc: Sent: Saturday, December 15, 2012 10:49 AM Subject: Re: Topband: Optimal radial wire type and gauge? ``````Read the N6LF radial papers and you will see that 1/8 wavelength radials are about as good as one can do. I use #14 stranded copper THHN wire because it is easy to work with. But how good can we get? For a 30' base loaded vertical I have 90 radials ```having an average length of 18 ft. The ground loss is 5 ohms, which is less ```than the loading coil loss. If I were to install 120 quarter wavelength radials I would gain 2 dB. Dave WX7G _______________________________________________ Topband reflector - topband@contesting.com `````` _______________________________________________ Topband reflector - topband@contesting.com ```