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Re: SSTC As a transmitter.



Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

Well, gosh, the effective aperture of a half wavelength wire is
substantially larger than its geometric physical aperture, for just the
reasons outlined in the quote from the patent.  
For what it's worth: Ae = .119*lambda^2 for a "short dipole" (Kraus,
Antennas,2nd ed, 2-20, page 44)
and 0.13*lambda^2 for a halfwave dipole.

Running some numbers... 30 MHz (10 meter lambda)... wire 1 cm in diameter,
5 meters long: Physical aperture = .05 meters^2 Maximum effective aperture
is 0.13 * 100 = 13 square meters.


Bear in mind that the collecting aperture (what determines the received
output power from the antenna)  is smaller than the effective aperture
(loss and reradiation).



> > The best that regeneration can do is modify the input impedance of
> > the receiver, which might happen to give it a better match to the
> > antenna.
> 
> This is in conflict with the following statement by John Sutton found in
> 1994 U.S. Patent  No. 5,296,866, "Active Antenna":
> 
>      "The reason why an antenna with regeneration has greater sensitivity
> than one without regeneration may be understood in terms of the concept of
> antenna "effective area."  The first to explain why an antenna may have an
> effective area larger than its geometric area was Reinhold Rudenberg in
>