[Antennas] RE: De-Icing Open Wire

Thu, 12 Dec 2002 14:38:09 -0600

Not quite true, Bob ---

A true "doublet antenna" is nothing more than a dipole, with one leg 
connected to each side of that 600-ohm feed-line!  For RF, it is a "closed 
circuit" but at 60 Hertz, it's an OPEN CIRCUIT.

I now wonder just how it worked at such low frequencies, since a 135-foot 
doublet isn't resonant anywhere near 60 Hertz....

Karl (now "Framistan") K - W8TIF
McKinney, Texas

-----Original Message-----
From:	Bob Wilder [SMTP:[email protected]]
Sent:	Thursday, December 12, 2002 7:39 AM
To:	[email protected]
Subject:	[Antennas] Open Wire

<snip>  The beauty of this antenna was that in
severe icing conditions Wilson would connect a 10V, 20amp filament
transformer across
the 600 Ohm open line and melt ice off of his antenna. Remember that a
doublet is a closed circuit, so the antenna appears as a short to the 
transformer.

<snip>

Bob Wilder, AF2HD/AFA2HD
6032 Idlemoore Court
Theodore, AL 36582-4117