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Still remember the Zepp Ant in front? If we apply it in the frequency of VHF above, that Mo the after of its Size decrescent we change it very easily into perpendicular erect. It became half perpendicular antenna. Appearance is like "J" , if pursue 7 (A) .
Perpendicular half characteristic is spoke angle of elevation very low, suit DX communication very much. If you have method erect the J Ant of a 28M Hz, you will discover it is quite fierce, not inferior at 3-Ele Yagi.
please Click here to get our dipole antenna
please Click here to get our dipole antenna
To the result of aerial increases in limited space, j-Ant can be out of shape for Slim-J Ant, this is Long Wire Ant from which fold two half, make originally phasic and contrary two Duan Banbo antenna turn via 180 degrees and become inphase, have the gain of 3 DB so, if pursue 7 (B) . Manage together, same skill also can apply in horizontal Zepp Ant.
If the graph is shown 8 times,additionally one kind adds the method of gain, fold half antenna among the antenna that is 3/2 λ originally STUB of 1/4 λ , became 2 Duan Banbo antenna to be in same way pile. Such, we can go up half antenna pile all the time in order to score gain (fold 2 paragraphs to make an appointment with 3dB, fold 4 paragraphs to make an appointment with 6dB) , this kind of skill comparatives in 144MHz and 430MHz practical.
The antenna that the author uses in 50MHz place is J-Ant namely, want to transmit a state to have only, 100mW can understand Japan, 3W amples ample have Yu, it serves to show it is low the work force of character of angle of elevation.
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