10-element yagi antenna for 70 cm

This is a short build description of a 10-element yagi for the 70 cm band, based on a design by DK7ZB 1.


The boom is a 15x15 mm aluminium square tube with a length of 2 m which is very lightweight.


The elements are 10 mm aluminium tubes, which are connected to the boom by 3d-printed element holders.

Reflector0 mm327 mm
Radiator140 mm315 mm
Director 1235 mm300 mm
Director 2425 mm287 mm
Director 3650 mm281 mm
Director 4920 mm272 mm
Director 51205 mm269 mm
Director 61495 mm269 mm
Director 71780 mm274 mm
Director 81995 mm269 mm


The whole construction was modelled in Autodesk Inventor and a 3D field simulation was performed to verify the design.

Farfield simulation

The farfield simulation results in a gain of 15.8 dBi, a 3 dB angular width of 32.5° and a front-to-back ratio of 30 dB.

Farfield simulation

Impedance Match

The feedpoint impedance of the radiating element is about 28 Ω. The simplest matching solution consists of two 75 Ω coaxial cables in parallel with a length of λ/4 2. The resulting line impedance of 37.5 Ω transforms the feedpoint impedance to 50 Ω. By coiling up the coax some common mode rejection can be achieved.