This 2 elements yagi antenna is intended for the 70cm UHF band center frequency is 410Mhz with 10Mhz bandwidth. The antenna measurements are computed and then simulated on 4Nec2 antenna modelling software.
Materials
- 1×1/2″ rectangular aluminum tubing for the boom
- 1/2″ aluminum tubing for the elements holder cut in half
- 3/8″ aluminum tubing for the antenna elements
- 1pc SO239 connector
- Pop rivets / Rivet tool
- #10 or #12 AWG copper wire with insulation for the gamma insert
- 3.5cm 3/8″ aluminum tube for the gamma tube
- 1 Butteryfly nut and 1bolt 18mm length 3mm diameter
- 4pcs Stainless steel nuts and bolts 20mm length 3mm diameter
- Aluminum plate 0.5mm thickness for the tuning stun
- Collapsible tubes different sizes.
- U bolt with mounting for the antenna mount
Construction
Measure and cut the boom according to the diagram and assemble the antenna following the antenna construction technique here. Of course you may improvised and follow your own construction technique the goal of the video is to help you visualize the technique I’ve used to build this antenna successfully – but everything is not set in stone.
Note: You may have downloaded a wrong copy of the diagram that sets the spacing to 30.2cm – that is incorrect sorry my mistake I uploaded a wrong version of the diagram when I initially uploaded the article. It has now been corrected with the diagram below.
Antenna Pattern from 4Nec2
Antenna Tuning
Here’s the antenna frequency response and tuning video on my Youtube Channel