Prezinta avantaje fata de variantele prezentate. Are polarizare orizontala si o banda de lucru relativ larga. Asezarea celor trei elemente componente, in forma unei frunze de trifoi (fig. 271), asigura o radiatie omnidirectionala.
Fiecare element formeaza un radiator in λ/2, alimentat la capete prin doua conductoare in λ/4, in forma de V (fig. 272). Impedanta la capete este de circa 30 Ω. Cele trei elemente fiind conectate in paralel, impedanta ansamblului este de circa 10 Ω, ceea ce impune un dispozitiv de adaptare pentru alimentarea printr-un cablu coaxial cu impedanta de 50—52 Ω. Acest dispozitiv este un „tub” central in forma de U (fig. 273).
Realizarea mecanica trebuie facuta cu grija, suportul central fiind executat dintr-o placa izolanta cu o rezistenta mecanica suficienta.
Citeva solutii simple. Folosind caroseria metalica drept priza de pamint, putem realiza o antena foarte simpla, cu o tija metalica de 57 cm lungime, fixata pe caroserie prin intermediul unui izolator si alimentata printr-un cablu coaxial cu impedanta 75 Ω (fig. 274).
Practic, vom realiza tija mai lunga si apoi vom decupa cite o portiune redusa pina la acordul maxim si ROS minim.
Daca avem montata pe masina o antena obisnuita metalica, pentru receptia emisiunilor de radiodifuziune, o putem adapta, pentru lucrul in banda de 144 MHz reducindu-i dimensiunile la circa 67 cm. Alimentarea se face cu un cablu coaxial de 75 Ω impedanta, printr-o capacitate de circa 6 pF (folosim un condensator cu capacitate variabila, vezi fig. 274). Acordul se face la baza tijei pentru ROS minim.
Daca receptorul de radiodifuziune montat pe masina are o intrare pe cablu coaxial de mare impedanta, aceasta poate fi conectata in paralel pe antena si vom putea simultan receptiona programele de radiodifuziune pe unele game de frecventa, transmitind in acelasi timp pe 144 MHz.
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