Greetings all
We are considering adding a second 160m antenna to an existing delta loop
at S54E station. The loop is fed for max. vertical polarization, but it is
tilted because we didn't have a support that would be tall enough to hang
it vertically. Therefore it probably produces a lot of horizontal high angle
radiation. The S54E station is on a top of a hill with quite steep slopes
(from 10 deg to 30 deg) in almost all directions. The slope angle gets
even bigger after few hundred meters and the far edge of the Fresnel zone
is not illuminated. The ground quality is rather poor. We are thinking of
a vertical antenna with radials sloping down the hill. The highest support
is about 35m, which is probably too low for a horizontal antenna.
I wonder how many of you have got a vertical on a hilltop ?
Where do we lose or gain comparing to a vertical on a flat terrain ?
Modeling a tilted vertical (20 degrees from vertical) over average ground
shows a 3dB drop of gain at 54 deg elevation. Subtracting 20 deg slope
angle would give us 34 deg. Have we simplified thing to much ?
What other effect would a ground slope have on a radiation pattern of a
vertical ?
Thanks to Mirko, S59X this msg. have some sense. :-)
73s & CU, Dan, S50U
SCC webmaster : http://lea.hamradio.si/~scc
______________________________________________________________________
Danilo Brelih HAM: S50U
Gorje #14 A email: danilo.brelih@siol.net
5282 Cerkno or: s50u@hamradio.si
Slovenia tel: +386 65 745 117
http://lea.hamradio.si/~s50e
______________________________________________________________________
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