40m 2el Yagi
This 40m yagi, which shows very high performance on our tests, isn’t ispired from any other model. Lots of yagi models are analyzed and this model figured out. The most spesific part of this model is having belove 1:5 < SWR value and 175khz bandwith.
Building and Equipments;
A- 100+20cm x 2 Pieces of 12mm aluminum rod.
12mm aluminum rod will be 2 pieces and 100cm long. Thats distance is (a)-(b) distance and it is important to set SWR easily. Because of that it is required to be 120cm (+20cm) each.
A- 1 115+20 x 2 Pieces of 12mm aluminum rod.
Same specifications with (a). It’s a reflector equipement and will be 2 pieces and 115cm long. Again it’s required to be 135cm each.
B- 300cm x 4 pieces of 30mm aluminum rod.
(a)-(b) distance is possible to make narrowing the rod from 30mm to 12mm. But in our first try we used clamps.
C- 275cm x 2 pieces of 40mm alimunim rod.
Between (b)-(c), plastic isolator will be used. In this antenna project linear lonet method is used instead of TRAP or coil. Just because there is a channel (groove) in our aluminum rods, we had that plastics with channel too.
D- Plastics will be 20cm long and two sides of it will be at the same diameter of the aluminum rods used.
E-K- This chapter is Linear Loadet chapter. It has to be as shown in the picture. Ledges will be 20cm long and has to be well tightened with clamps.
F- BOM is made from aluminum plate and tightened with exhaust clamps. 54 and 60 size clamps used.
G- BOM must be 50mm dia, 6mt long and minimum 1,5mm width.
H- 55cm long two aluminums are important to build rods and carry the wing weights. It must be as shown in the picture. Reflector part has to be mounted to the Bom with a 54 size exhaust clamp. Also L Aluminums are got to be mounted to reflector as shown in the picture.
I- Plastic isolator is processed in lathe to suit 40mm aluminum. And it’s all isolated with a plastic pipe around it. Also Haarpin Mach and 1:1 balun used. These are tightened to Bom with clamps too. The distance between Haarpin Mach and balun connection points is 30cm. But it suited the bom as shown in the picture.
Haarpin Mach: 16cm x 60 cm
Aluminum equipements used in this project are choosen form hard and light equipements.