What about shorting together the circumference in a ring?
How does that affect the angle?
MK
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of N5KM
- Kris
Sent: Wednesday, March 02, 2016 12:07 AM
To: towertalk@contesting.com
Subject: [TowerTalk] Pseudo-Brewster Angle
Reading the thread about an effective radial system got me thinking about
the pseudo-Brewster angle of a 1/4 wl vertical antenna. As strictly a mental
exercise, I calculated how much radial wire would be needed for an 80m
vertical Fresnel zone that results in a low (1-2 degree) pseudo-Brewster
angle. Assuming 120 radials of 5 wavelengths each that comes to 30 miles of
wire on a parcel of at least 122 acres.
The tips of the radial will be 68 feet apart. This raises the question is
this too far apart to affect the pseudo-Brewster angle? Devoldere says yes
(Low-Band DXing, 3rd ed.). He says they need to be no more than .05 wl (13
feet) apart.
The return
currents will be nearly entirely collected by the close-in parts of the
radials. So that's not an issue. John doesn't show the math or other
analysis that leads to the
.05 wl figure so I'm not entirely convinced it's needed. However, if true,
that would require an additional 60 miles of wire.
Kris N5KM
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|