Construction Details

3-El.-10m

 4-El-10m

3-El-12m

4-El-12m

3-El.-15m

 4-El.-15m

3-El.-17m

4-El.-17m

3-El.-20m

 4-El.-20m

5-El-10m

4-Element-20m-Yagi with 28Ohm

Boom 7,60m

Short data for the Yagi at the begin, in the middle part and at the end of the band

Plot with the NEC-II-reference of YO7.2 by K6STI

The meaning of the data :

Frequency, gain, F/R, radiation resistance (impedance), SWR and loss against a theoretical defined maximum- gain-Yagi with the given boomlength. Remember  that this gain is only available with very low impedance and extrem low bandwidth!

 Elements of the 4-El.-20m-28Ohm-Yagi, lengths for one element-half: 

 

25x2mm

20x1,5mm

16x1mm

12x1mm

Position

Ref

1,50m

1,00m

1,00m

2,00m 0m

Rad

1,50m

1,00m

1,00m

1,855m 1,8m

Dir 1

1,50m

1,00m

1,00m

1,67m 3,4m

Dir 2

1,50m

1,00m

1,00m

1,375m 7,6m

 

Azimuth-diagram (horizontal pattern):

Elevation-diagram (vertical pattern):

Gain, SWR, F/R and Z versus frequency: