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Re: Topband: Rhombics

To: "Mike Waters" <mikewate@gmail.com>, "topband" <topband@contesting.com>
Subject: Re: Topband: Rhombics
From: "Tom W8JI" <w8ji@w8ji.com>
Reply-to: Tom W8JI <w8ji@w8ji.com>
Date: Fri, 26 Jul 2013 16:16:00 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
I think rhombics were sometimes chosen for receiving, because they are a
type of wave antenna like the Beverage but with a sharper pattern. But how
the two compare, I can't say.

Rhombics, because of the many small lobes, have poor directivity. As such, they are not exceptionally good receiving antennas.

As Rudy pointed out:

"People tend to forget that rhombics were originally used for point-to-point
communications with fixed azimuths and distances.  While the gain was nice
the real utility was the broadband character of the antennas, especially
when terminated.  This allowed the transmit/receive frequencies to be
quickly changed as propagation along a given path varied."

Log periodics relaced them for bandwidth (with similar or slightly less gain), and curtains replaced them for increased gain (with loss of SWR bandwidth).





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