Details for all Yagis 1-El.-50Ohm 2-El.-28Ohm 3-El.-28+50Ohm
4-El.-50Ohm (0,76m) 4-El.-28Ohm (0,76m) 4-El.-28Ohm (0,82m) 4-Ele.-28-Ohm (1,00m)
5-Ele.-28+50-Ohm (1,50m)  5-Ele.-28-Ohm (1,80m) 5-(6)-Ele.-28-(50)-Ohm (2,00m) 6-El.-28-Ohm (2,40m)
6-El.-28-Ohm (2,60m) 7-Ele.-28+50Ohm (3,00m) 7-Ele.-28-Ohm (3,30m) 8-Ele.-28-Ohm (4,35m)

5-Element-Yagi with the 28-Ohm-DK7ZB-Match, Boom 2 m

2x 6-Element-Yagis with the 50-Ohm-DK7ZB-Choke, Boom 2 m and 2,1 m (see down)

5-Element 28-Ohm-Type

Boom 2m, Gain 9dBd, F/B > 20dB 

 

Stacking distances

2,40m vertical

 2,55m horizontal

Left:

4x5-Element stacked at DL0BL

Contestcrew DL0BL  

Link with more pictures/infos

 

Antennas in H-configuration, built by Piotr, SP9TTG

Elementpositions and Elementlengths

Diameter Refl Rad (10mm) Dir 1 Dir 2 Dir 3
Position 0mm 410mm 815mm 1475mm 1970mm
Elements 10mm 1022mm 958mm 911mm 916mm 880mm
Elements 8mm 1024mm 958mm 919mm 922mm 888mm
Elements 6mm 1026mm 958mm 927mm 929mm 897mm
Elements 4mm 1028mm 958mm 937mm 938mm 907mm

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!

6-Element-Yagi with the 50-Ohm-DK7ZB-Choke, Boom 2 m

Broadband design, lower F/B

Gain 9,3dBd    F/B 18dBd

3dB-hor  46,8°

3dB ver  56,2°

Stacking distance 2,40m

Elementpositions and Elementlengths

Diameter Refl Rad  Dir 1 Dir 2 Dir 3 Dir 4
Position 0 mm 260 mm 393 mm 845 mm 1470 mm 1980 mm
Elements 10 mm 1027 mm 983 mm 922 mm 910 mm 910 mm 882 mm
Elements 8 mm 1028 mm 987 mm 930 mm 918 mm 918 mm 890 mm
Elements 6 mm 1030 mm 993 mm 940 mm 927 mm 927 mm 900mm

6-Element-Yagi with the 50-Ohm-DK7ZB-Choke, Boom 2.1 m

High gain, narrowband design, excellent pattern

The Yagi right is built by Yoichi, JR4MDA

more on his page  JR4MDA

Gain 9,46 dBd    F/B >= 30 dB

3dB-hor  45,0°

3dB ver  53,2°

Stacking distance 2,45m

 
Here a report of Jean-Jaques, ON7EQ, with hints for tuning the antenna:
 

At present building an array of 2x  6 ele for 2m , according to your design attached. I was particularly charmed by the very clean 'backlobes'  of the antenna, while offering a very high forward gain despite the short boom.  Maybe not the best antenna for contesting (deaf in the back), but good for EME / MS !

 
Off course, this at the cost of a very narrowband  design ...
 
I have constructed all with utmost precision, using 10mm elements with KONNI  insulators on a 20x20 boom.
 
Found antenna resonating @ 145.0 MHz instead of 144.350 about (according to your info and reproducing it in EZNEC).
 
I hereby just wanted to attract the attention of fellow hams that the resonance frequency can be smoothly changed by finetuning the lenght of D2 (not the radiator !) . This has the most effect on frequency, while the SWR stays 1:1 @ resonance. So my hint is to make D2 perhaps 3mm longer on both sides of element, and then file tips to adjust towards 144.350.

 

Elementpositions and Elementlengths

Diameter Refl Rad  Dir 1 Dir 2 Dir 3 Dir 4
Position 0 mm 280 mm 415 mm 840 mm 1485 mm 2075 mm
Elements 10 mm 1014 mm 976 mm 950 mm 928 mm 921 mm 880 mm
Elements 8 mm 1018 mm 983 mm 957 mm 934 mm 928 mm 889 mm
Elements 6 mm 1020 mm 994 mm 966 mm 942 mm 936 mm 901mm