Re: Evo kako se stvarno pravi antena
ja sam dobio malo drugacije podatke vezano za duzinu direktora ,ne znam za koju si frekvenciju dao taj proracun.
kod mene ispane ovako.
i pravio sam po tome kako je pisalo,ali nisam zadovoljan rezultatima.
ono sto me zanima jest, koja debljina zice je najbolje uzeti za yagi antenu, i koliki precnik dipola uzeti.
zbunjuje me to sto se svi podaci proizvoljno uzimaju.
nema vrijednosti koje se preporucuju, sa kojima bi bili najbolji rezultati.
Yagi design frequency =2422,00 MHz
Wavelength =124 mm
Elements using a non-metallic or separated boom
Director/reflector diam =2,70 mm
Radiator diam =2,70 mm
ELEMENT LENGTHS AND SPACING
Reflector
60 mm long at boom position = 30 mm
Radiator
Single dipole 57 mm tip to tip at boom posn =55 mm
Folded dipole 58 mm tip to tip at boom posn =55 mm
Dir Length Spaced Boom position Gain Gain
(no.) ( mm ) ( mm ) ( mm ) (dBd) (dBi)
1 50 9 64 6,9 9,1
2 50 22 86 7,9 10,1
3 49 27 113 8,8 11,0
4 48 31 144 9,7 11,8
5 48 35 179 10,4 12,5
6 47 37 216 11,0 13,2
7 47 39 255 11,6 13,7
8 46 41 296 12,1 14,2
9 46 43 338 12,6 14,7
10 45 45 383 13,0 15,1
11 45 46 429 13,4 15,5
12 44 48 477 13,7 15,9
13 44 48 525 14,0 16,2
14 44 49 574 14,4 16,5
15 44 50 624 14,6 16,8
Director spacings are measured from the previous element
Tolerance for element lengths is +/- 0 mm
Boom position is the mounting point for each element as measured
from the rear of the boom and includes the 30 mm overhang.The total boom length is 654 mm including two overhangs
The beam's estimated 3dB beamwidth is 29 deg
Here are some construction details for a folded dipole
Measurements are taken from the inside of bends
Folded dipole length measured tip to tip = 58mm
Total rod length =146mm
Centre of rod=73mm
Distance HI=GF=12mm
Distance HA=GE=36mm
Distance HB=GD=59mm
Distance HC=GC=73mm
Gap at HG=4mm
Bend diameter BI=DF=30mm
If the dipole is considered as a flat plane (see ARRL Antenna Handbook) then its resonant frequency is 2422,0MHz and K is 0,900
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Re: Evo kako se stvarno pravi antena
Re: Evo kako se stvarno pravi antena
