[Antennas] W3EDP and mobile antennas

[Chris BONDE]

I have read something like this.  But this has been put a little better.

But this brings to mid another question.  An inverted "L" is suggested for 
160m.  When would the horizontal become a cap hat or when would the cap hat 
become the horizontal part of the inverted "L".  I have readc some of 
Cebik's articles on cap hats.  Very interesting, spirals (one and two 
elements. ) 'radials' ends connected with circle or not.  Many forms, but 
when would it be called a cap hat or a horizontal part, when only one?

Chris opr VE7HCB



At 07:37 PM 2002-05-19 -0400, you wrote:
>The radiation resistance will increase as the square of the height for
>radiators much smaller than a quarter wavelength.  So 16 feet gives you 4
>ohms, and 32 feet gives you  about 16 ohms.  A capacitive top hat will
>increase the effective height by 50 to almost 100 %, depending on how big the
>top hat is.  The biggest top hat I know is the Cutler Maine VLF antenna.  It
>uses something like 8 -1000ft towers to create a top hat acres in size.  They
>get to almost 50% efficiency at 30 KHz ( and 1 megawatt ERP).
>Ed