Vertical antenna at 144 MHz. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / VHF antennas
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The described antenna is produced in Belgium under the name "BIG STAR".
The antenna is a system of vertical collinear vibrators with a circular radiation pattern in the horizontal plane.
Fig. 1
The theoretical gain of the antenna is 6,5 dB with respect to a half-wave vibrator. Experimental verification showed that at a distance of 100 km, the transition from the dipole to the described antenna gives a gain of 9 dB. The total height of the antenna is about 5 meters.
The electrical circuit of the antenna is shown in fig. 1, constructive implementation in fig. 2 - 6. The vibrator is made of duralumin tubes broken with Teflon insulators.
Antenna tuning is reduced to moving the point of connection of the central core of the cable to inductance C until resonance is obtained at the operating frequency.
This antenna was used when working through RS series satellites and showed good results, especially when the satellite is low above the horizon
Literature
- "QTS" 4/92. SP2FBC & SP2MBE
Publication: cxem.net
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