Hi Jim,
The NORD antenna is a relatively inexpensive low frequency
antenna (typically used at 50-100 kHz) where its impossible to
achieve vertically polarized antennas with close to 1/4 wavelength
vertical height.
The NORD antenna typically consists of an electrically short folded
unipole (typically less than 0.05 wavelength tall) with at three
(or more) umbrella wires attached to the top of the vertical spaced
evenly spaced at 120 degree intervals
Unlike umbrella antennas used on topband (such as in my W8JI/W5ZN
8-circle receiving arrays), the NORD antenna also uses a capacitor
at the end of each umbrella wire. The three capacitors are used to
tune the antenna, avoiding the need for a lossy loading coil at the
feedpoint of the antenna,
The NORD antenna is a poor choice for T opband where many of us
can use much more efficient quarter wavelength inverted-L antennas
or in some cases full size quarter wavelength verticals.
To learn about the NORD antenna simply Google: "NORD Antenna"
73
Frank
W3LPL
----- Original Message -----
From: "James Rodenkirch" <Rodenkirch_LLC@msn.com>
To: "Top Band Contesting" <topband@contesting.com>
Sent: Tuesday, February 2, 2016 4:12:27 PM
Subject: Topband: NORD antenna for top band.....
.....anyone experimented with a NORD-configured vertical antenna?
I have the Navy antenna publication -
http://www.hamuniverse.com/US%20NAVY%20Antennas%20and%20Wave%20Propagation.pdf
- but, other than a brief description, not much to go by....any assistance,
e.g., steerage to a web site or empirical data/analysis results appreciated.
Antennas and Wave Propagation - HAM
RADIO<http://www.hamuniverse.com/US%20NAVY%20Antennas%20and%20Wave%20Propagation.pdf>
www.hamuniverse.com
NONRESIDENT TRAINING COURSE . Antennas and Wave Propagation. DISTRIBUTION
STATEMENT A: Approved for public release; distribution is unlimited.
72 de Jim Rodenkirch K9JWV
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