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Topband: 2 wl loop, worth the effort?

To: topband@contesting.com
Subject: Topband: 2 wl loop, worth the effort?
From: Rob Atkinson <ranchorobbo@gmail.com>
Date: Wed, 2 Dec 2015 11:53:39 -0600
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Hi Gary, It would make a nice receiving antenna.

Let's start with a question:  Would you put up a loop for 20 meters
that is 6 feet off the ground?  Height for horizontal antennas must
always be thought of in terms of _wavelength_.  There is only one
effective transmitting antenna for medium wave, assuming you do not
have 200 foot tall supports for stringing up a horizontal wire
antenna, and that is some sort of monopole over a good ground system.
Period.  And good ground system means a lot of radials.  A lot.  Not
10 or 20.  You don't get to cheat on the laws of physics.  You have to
bite the bullet and do the work.  The excited vertical part has
options.  T, inverted L, or an insulated tower are all fine provided
the vertical part is at least 50 feet tall (more is better).

Don't take this personally--it's just that I get tired of piss weak
signals on 160 from hams who seem to think they have an exemption from
Mother Nature.  A dead giveaway that a ham is using a low dipole, 20
feet or so, is rapid deep QSB.  Even 50 feet is too low.  Inverted Vs
are worse.  the effective height is halfway between the apex height
and the height of the ends.  A big horizontal loop on transmit does
nothing for you but cause more of your RF to get lost to ground
coupling.

73

Rob
K5UJ
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