Topband: Radial system gain

Tom Rauch w8ji at
Fri Sep 29 19:11:58 EDT 2006


>>1.) An absolute perfect zero loss ground system (available
>>only in theory) and a 1/4 wave vertical produces a field
>>strength of about 196mV/m at one mile with one kilowatt.
>>That's zero elevation angle, so we are looking at low wave
>>2.) B,L, and E using reliable measurements on 3MHz 
>>192uV/m with 113 radials about 1/2 wl long. That's 0.4dB
>>below a perfect conductivity sheet.

That's wrong. I said .4dB and it is 20 log 192/196 or  0.2dB

and that makes this wrong

>>3.) 60 radials under the same conditions produced about
>>185uV/m. That's 0.5dB below a perfect sheet. One tenth dB 
>>gained by almost doubling the radials to 113,

We would gain a whopping 0.2 dB going from 60 radials to 113 
radials when the radials are 1/2 wave long,  not  1/10th dB. 
60 radials is still 1/2 dB below a perfect solid sheet, but 
the 113 radials are about .2 dB dB better.

So for all that extra work of doubling the radials from 60 
to 120 you would get about 0.2dB.

73 Tom 

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