Apologize for earlier half-done post. Spastic hit on send key.
See http://www.fybush.com/sites/2005/site-051028.html for a Franklin and a
nice article.
For 1530 kHz, that's a *pair* of two vertical halfwaves in phase. 50 kW
gives 3545.89 mV/m for broadcasting purposes. Note the relative lack of
neighbors, and therefore lack of 24 hour miscellaneous diodic signal
demodulation, talking window screens, permanently lit florescent bulbs, etc.
Note that this monster is not too far from 160m. Think big and put an only
slightly downsized 160 version out in the salt shallows somewhere on the
western side of Cheasapeake Bay. Without any controversy whatsoever as to
ground induction losses (zero) EZNEC says this would put 13.6 dbi gain
toward Europe at 3.1 degree takeoff. Order of magnitude: three element yagi.
Just for comparison, if I drain Chesapeake Bay and fill it with concrete
rubble and other urban debris (can do magical things in EZNEC) I get 5.0 dbi
at 12.9 degrees. The full EZNEC preloaded table follows, filling Chesapeake
Bay with other dirt, or turning it into a fresh water lake. These figures
are *without* any ground field copper underneath, as it is not needed for a
current sink and I have no data on what kind of field might actually be
employed.
Urban debris: 5.0 @ 12.9d (-5.0 dB from that angle takeoff over seawater)
Sandy 4.8 @ 10.7d (-6.6)
Rocky, poor 5.2 @ 10.6d (-6.2)
Average 5.4 @ 9.0d (-6.8)
Forest 5.7 @ 8.7d (-6.6)
Marshy 6.1 @ 8.4d (-6.0)
Rich pastoral 6.8 @ 8.1d (-5.8)
Very rich 9.1 @ 7.1d (-3.8)
Fresh water 8.4 @ 8.9d (-3.8)
Salt water 13.6 @ 3.1d (0)
One can dream. 73, Guy.
On Fri, Sep 23, 2011 at 1:21 AM, Herb Schoenbohm <herbs@vitelcom.net> wrote:
> George, Are you familiar with the Franklyn antenna design?
> Some broadcasters swear by them and claim a 3 db increase over a 1/4
> vertical radiator.
>
> Herb, KV4FZ
>
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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