Quad antenna

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The Quad antenna, sometimes called the Cubical Quad, is an antenna which is frequently used by amateur radio operators. Developed by Clarence C. Moore (patent no. 2,537,191), W9LZX, an engineer at HCJB (a shortwave missionary radio station high in the Andean Mountains). He developed it to resolve issues with large coronal discharges in the thin air with a beam antenna.

Moore describes his antenna as "a pulled-open folded dipole" and describes the time when it was developed:

“

We took about one hundred pounds of engineering reference books with us on our short vacation to Posoraja, Ecuador during the summer of 1942, determined that with the help of God we could solve our problem. There on the floor of our bamboo cottage we spread open all the reference books we had brought with us and worked for hours on basic antenna design. Our prayers must have been answered, for gradually as we worked the vision of a quad-shaped antenna gradually grew with the new concept of a loop antenna having no ends to the elements, and combining relatively high transmitting impedance and high gain.

”

[edit] Quadloop Antenna Model QA-2F

The quad antenna was originally designed in the late 1940's. It was found out that the quad has a slight gain of approximately 2 dB over a dipole. The quad antenna model QA-2F is specifically designed to operate in the frequency band of 140-150 MHz. It displays a bi-directional radiation pattern with maximum radiation in the direction perpendicular to the plane of the loop. An SWR response of less than 1.5:1 over the entire band is attainable according to the author.

[edit] Patents

• Patent 2,537,191

[edit] References

• All about Cubical Quad Antennas by William I. Orr
• Quadloop Antenna Model QA-2F from the book PRACTICAL ANTENNA DESIGN second edition, Philippine copyright, 1990, 1994 by Elpidio C. Latorilla