Well Rob, if you read Gary's email, you will find that he is interested in
communicating "...with the hams I daily keep in touch with in the 500-600 mile
range." The loop may be a great antenna for this but not, as you say, so much
for DXing.
But there is, in my view, a deeper issue here. I t's the "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" theorem. For many of us, compromise is built in
to our situation, we are not being obstinate just to pee you off. In my case, I
have a 110 X 50 foot property in a residential neighborhood and I am limited to
a "T" transmit antenna (40 ft up, 92 ft flattop) and a K9AY RX array in a
somewhat noisy neighborhood. So no, I don't hear or TX like those with a more
favorable QTH, but I enjoy 160 meters, I have fun and do the best I can with
what I have. So if I occasionally call out of time (I try not to) because I
don't have the "ears" you do, don't take it personally...
73 Kevin K3OX
----- Original Message -----
From: "Rob Atkinson" <ranchorobbo@gmail.com>
To: topband@contesting.com
Sent: Wednesday, December 2, 2015 12:53:39 PM
Subject: Topband: 2 wl loop, worth the effort?
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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