. QST . ctor spaced Imp. of radiatorGain over dipole 50 ohms5db. The gain figures seem high but they are theactual readings obtained. The radiating elementalone, without reflector or director, gave a con-sistent gain of 2 db. over a well-matched and and reflector. Such a beam might prove consider-ably better than a three- or four-element limitations prevented investigating thesepossibilities, but it is hoped that the above exper-imental work will stimulate more work on thequad by other amateurs. This beam is worthmuch more attention than it has received in thepast. The 20-meter
. QST . ctor spaced Imp. of radiatorGain over dipole 50 ohms5db. The gain figures seem high but they are theactual readings obtained. The radiating elementalone, without reflector or director, gave a con-sistent gain of 2 db. over a well-matched and and reflector. Such a beam might prove consider-ably better than a three- or four-element limitations prevented investigating thesepossibilities, but it is hoped that the above exper-imental work will stimulate more work on thequad by other amateurs. This beam is worthmuch more attention than it has received in thepast. The 20-meter quad here at W5DQV has createdconsiderable interest, nearly half the stationscontacted asking for more information aboutits operation and construction. After fourteenmonths operation on 20 , this antenna hasproven its worth as it has given results equal toand often superior to the three-element wide-spaced beam it replaced. It is definitely smallerthan the usual three-element beam, having a Reflector. Reflectot Radiator-* , All sides■4 wavelenqtfi- ^Stub trimmed dipole. This does not agree with thepublished figures for a square loop; nevertheless,this 2-db. gain was obtained on two differentoccasions, using different loops and differentdipoles, all grid-dipped to the correct length. Dis-regarding this 2-db. gain of the square loop, spaced quad still gives a gain of 8 db., a veryrespectable gain indeed. A field pattern taken with the reflector at shown in Fig. 2. A pattern taken at a similar outline but with somewhatgreater attenuation of the back lobe. The radiation from the sides of these test beamsand the one used on 20 meters was remarkablylow, the field-strength meter indicating almostzero off the sides. On-the-air tests with the 20-meter quad showed a 45-db. front-to-side ratioand 25-db. front-to-back ratio. A square elementtuned as a director and spaced wavelengthgave a gain of 5 db. over the dipole, which bringsup the interesting poss
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectradio, bookyear1915
