[Premium-Rx] Broad Bandwidth HF RX Antenna + NVIS Antenna

[Gary Mitchelson - N3JPU]

NVIS is most used in the 2-8 MHZ range, not VHF or UHF. A great NVIS antenna
is the Loop antenna (see links below). 

I suggest the following mail group:
http://groups.yahoo.com/group/NVIS/

Cebik's website:
http://www.cebik.com/cb.html

And this great book:
http://www.wr6wr.com/newSite/products/books/nvisc.html


-----Original Message-----
From: premium-rx-bounces at ml.skirrow.org
[mailto:premium-rx-bounces at ml.skirrow.org] On Behalf Of Ahmet Gundes
Sent: Thursday, January 29, 2004 23:22
To: Premium-RX
Subject: [Premium-Rx] Broad Bandwidth HF RX Antenna + NVIS Antenna

Most NVIS antennas used by the military ( you can find some explanation on
this issue on the web site of Shakespear 
company that makes NVIS antennas ) are for VHF and UHF. 

This is basically due to the size/construction contstraints. These antennas
are used on military vehicles and size is limited naturally. In order to
have NVIS / High Incident 
angle, the antenna is made quite cleaverly as a Center
Fed Vertical Dipole ( most companies keep this as a little trade secret ).
These antennas have "near vertical" dipole performance. They can be used
usually as low as 30MHz as they are made to cover the military VHF bands.
However if the vertical you have is not a Center-Fed Vertical and it is a
military monopole type then they are not NVIS type antennas in its true
sense.  The "old" Telex 4331 is a Center-Fed Vertical and I believe you can
get these from surplus dealers. I have not seen any NVIS HF antennas that
can go down to 
say 15MHZ range or so. They would have to be made for special orders and
they are not commercially available.