|4-El-12,5-Ohm (2,90 m)||
4-El-12,5-Ohm (3,60 + 4,00m)
|5-El-12,5-Ohm (6,00 m)|
|7-El.-28+50Ohm (9,20+7,75 m)||8-El.-28-Ohm (12,30 m)||9-El.-28-Ohm (14,00 m)|
|4-El-28+50-Ohm (2,20 m)||5-El-50-Ohm (4,30 m) new||6-El-50-Ohm (6m+7,20 m) new|
4-Element- 12,5-Ohm-Yagi with 3,60m-Boom
(A 4m long Yagi see down)
Short data: Gain 8,2dBd, F/R >26dB, bandwidth 300KHz (50.0-50.3 MHz) at SWR < 1.5
This type is in use at the station DL8FAJ and was at DL8FBC, both worked WAC in 2000/2001
Picture shows the homemade Yagi by ZP5YW.
Match with 2x lambda/4 50-Ohm-coax in parallel to a grounded socket, feedpoint impedance 50 Ohm.
An other construction for the radiator is a folded dipole with an impedance of 50 Ohm (4x12.5 Ohm). At the feedpoint use a toroid balun 1:1 (T 200-6) or a simple coax-choke to match the symmetrical load to the coax-cable.
Important: The antennas have extremly high gain and F/B for the given length, but bandwidth is small and the yagis needs a very free surrounding. You must mount the Yagi on a separate mast, not together with other antennas!
The table for 12-mm and 10-mm-elements (also radiator), no tapering
|Element||Position||Length (12 mm)||Length (10 mm)|
|Ref||0 mm||2980 mm||2986 mm|
|Rad||750 mm||2818 mm||2826 mm|
|D 1||2075 mm||2746 mm||2756 mm|
|D 2||3580 mm||2686 mm||2700 mm|
with 4,00 m-Boom
Gain 8,5 dBd, F/B 24 dB
High-Gain Design, small Bandwidth
Matching with 2x1,23 m coax Aircell-5
The stacked array 4 over 4
The measurement below shows the SWR and the impedances of one Yagi. Built without any fine-tuning!
Compare the simulated and the measured data! Read the procedure for the fine-tuning of the radiator and D1 at the page "Construction Details".
The table for 12-mm, 10-mm and 8-mm-elements (also radiator), no tapering
Mounting with insulated clamps above the boom
|Element||Position||Length (12 mm)||Length (10 mm)||Length (8 mm)|
|Ref||0 mm||2948 mm||2952 mm||2954 mm|
|Rad||860 mm||2796 mm||2802 mm||2814 mm|
|D 1||2340 mm||2730 mm||2742 mm||2755 mm|
|D 2||3970 mm||2664 mm||2670 mm||2686 mm|