Is the loss equal for all vertical radiation angles ?
----- Original Message -----
From: "Steve Hunt" <steve@karinya.net>
To: <towertalk@contesting.com>
Cc: <towertalk@contesting.com>
Sent: Friday, January 14, 2011 4:54 PM
Subject: Re: [TowerTalk] Fw: ground radial project
> Jim,
>
> Agreed!
>
> If folk would look carefully at the Brown/Lewis/Epstein paper they would
> see that it's not so different from Rudy Severn's work. Figure 30 in
> their paper plots received field strength against number of radials for
> a quarter-wave vertical radiator. Compared with the theoretical maximum,
> these are the shortfalls they measured:
>
> 15 radials: -2dB
> 30 radials: -1.3dB
> 60 radials: -0.7dB
> 113 radials: -0.2dB
>
> To me that doesn't look like a strong case for 120 radials in Amateur
> Radio useage!
>
> 73,
> Steve G3TXQ
>
> On 14/01/2011 21:26, jimlux wrote:
>> That 120 radial thing is from Brown, Lewis and Epstein, and was
>> originally formulated as a FCC shortcut to avoid having to do a proof of
>> performance on a non-directional AM transmitter (i.e. rather than spend
>> the money to measure field strength on all the cardinal radials and so
>> forth, you could say, we've installed the FCC standard ground field).
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