Christoph Petermann DF9CY 2008

Last Revision: 02 June 2008


The ZX 6-6 Yagi Antenna with 2m and 70cm Antennas above

Intention

I put up this 6 element yagi (ZX Antennen) in May 2008. The claimed gain is 12,5 dB (dBd or dBi ??). I wanted to know, if the antenna is as good as it is claimed. Here are some results of the simulation I made with EZNEC+.

The antenna is very rugged and heavy (ca 18kg). Hopefully this helps against the raven birds and the 160km/h wind gusts.

Antenna Dimensions


For the simulation I corrected the elements lengths. I deducted 20mm from each element, to correct for the boom diameter. The elements are mounted with large clamps on the 50mm diameter boom. I think I get close to the real value by doing so. The values above are the values given in the datasheet.

AZIMUTH Diagram in Free Space


ELEVATION Diagram in Free Space

The Antenna at 9,6m above ground level

The Antenna at 9,6m above ground level (Primary) compared to the same antenna at 25m.

This simulation shows the advantage of an antenna mounted high above the ground. If you compare at an elevation angle of 3 you will see more than 6 dB of gain. And that is the difference regarding DX signals. I can not realize this ... Nevertheless comparing with my old 4 element antenna I can see a big improvement. The clean pattern make a very noise-free band. It is very astonishing, that I can hear many backscatter now, which were "not there" with the smaller antenna.