[Elecraft] Magnetic Loops

[Dave - AB7E]

I think I saw the article for that one myself, or at least a similar one by somebody else.  I guess very low profile would be the major advantage of one for mobiling, but almost anything else would be a better choice for any other application.

I actually built a DDRR about 40 years ago (for 20m, I think) comprised of wire laid out on the floor of my apartment in Cedar Rapids, Iowa.  That was back when it was still touted as a "Directional Discontinuity Ring Radiator" ... an erroneous description akin to the silliness of the more recent EH antenna claims.  I pumped 100 watts into my DDRR and made several contacts, but the RF burns it put out if I got too close to it were very painful.

73,
Dave   AB7E



------Original Mail------
From: "David Cutter" <d.cutter at ntlworld.com>
To: "Dave - AB7E" <xdavid at cis-broadband.com>,
    <daleputnam at hotmail.com>,
    <gary at isect.com>,
    <elecraft at mailman.qth.net>
Sent: Tue, 4 Aug 2009 06:51:19 +0100
Subject: Re: [Elecraft] Magnetic Loops

G3LDR made one as a roof rack many years ago; designed for 20m as I recall.

David
G3UNA





That's not really true.  The DDRR is NOT a loop antenna.  The DDRR is a very 
short vertical with top loading contributed by a shorted transmission line 
(formed by the horizontal loop and the ground plane).  Check the field 
polarization ....

73,
Dave   AB7E




Hi Gary,

  Seems to me that you are right on with all but the very last part... and 
that may need some investigation, with relation to the DDRR antenna.. that 
is a loop, and horizontal, over a very good ground. Just a thought....

--... ...-- Dale - WC7S in Wy