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Old August 4th 08, 09:40 PM posted to rec.radio.shortwave
Telamon Telamon is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 4,494
Default August Popular Communications

In article Urxlk.4105$nu6.2885@edtnps83, m II wrote:

On Sun, 03 Aug 2008 12:26:26 -0700

Telamon wrote:

This issue has a good antenna article on loop antennas but for some
strange reason the author seems to think it is only a good AMBCB
antenna. This antenna type is excellent for SW also. Depending on what
frequencies you want to the antenna to operate on and the circumference
of the loop you will not need a matching transformer. Closed loop
antennas are generally superior in urban environments with local noise
sources for a number of reasons.

There is also a good article on propagation by Tomas Hood.



Have you heard anything about those hula-hoop sized loops? If I can find a
suitable tuning capacitor I might try building one. The directional abilities
look useful.


A hula-hoop size loop will be large enough if you can tune it to
resonance with a capacitor. I have not used a small tuned loop for SW
but the experiences of others indicate that unlike AMBCB the SW signals
are more scattered in the ionosphere and so are more difficult to null.
You should have good success on the lower SW bands but should expect
poorer nulling the higher in frequency you go.

I do use larger single turn loops for AMBCB and SW. I have noticed that
they appear less directionally selective at higher frequencies.

The article in Popular Communications show several types of single turn
wire loop antennas if you are interested.

--
Telamon
Ventura, California