Miniature directional antenna for the range of 144-146 MHz. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / HF antennas
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A description of a new type of antenna for the 2 m band was published in "REF Radio" N 12/89 and N 1/90. The authors of this antenna - F6HLZ and FC1MZO believe that their design will revolutionize the shortwave world. The author's idea is protected by a French patent, but the authors allowed the publication.
Fig. 1
Presenting four versions of this antenna, we restrict ourselves to short characteristics and design features.
Version N1. They form two equilateral triangles with a side size of 250 mm. The triangles are arranged horizontally, one above the other, at a distance of 292 mm. Adjusting this distance affects the SWR value, and the gain achieved is XNUMX dB.
Version N2. This is a modernized antenna of the N1 version, to which the so-called "bat" has been added (marked and highlighted in Fig. 1). In this case, the antenna gain reaches 8 dB.
Version N3. Two reflectors have been added to the N2 version antenna. Gain reaches 12 dB.
Version N4. Three reflectors have been added to the N2 version antenna. In this version, the gain reaches 18 dB. The ratio of radiation forward / backward - 20 dB. Sidelobe suppression - 24 dB.
Rice. 2 (click to enlarge)
Another evaluation of the performance of this antenna was made by comparing the readings of the S-meter with the same signal source. With the GP antenna - S - 1, when with the F6HLZ antenna (version 1) S - 3, (version 2) S - 4, (version 3) S - 4, (version 4) S - 5.
Fig. 3
On fig. 1 shows the antenna version N 4. For horizontal polarization - shown in fig. 2. In fig. 3 shows the connection of the cable to the antenna shown in fig. 1. Power cable - 50 Ohm.
Literature
- SP2FAV, "QTC"N3 1992
Translation from Polish by S. Popovich (UC2LAQ); Publication: cxem.net
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