How to Build an Effective Yagi Antenna
- 1). Use any Yagi element calculation software (Resource 1) to determine the length of your elements for your desired antenna frequency.
- 2). Cut each of the elements to the length indicated by the software with the hack saw.
- 3). Drill a hole at the point indicated by the software into the center of the boom to allow for the aluminum tubing element to fit into it so that the boom and element are perpendicular. The element must be tight to ensure an acceptable electrical connection.
- 4). Repeat step 3 for each of the elements as indicated by your software.
- 5). Attach the perforated aluminum sheet to the boom by drilling a hole in its center for the boom to pass through. The sheet should be parallel to the elements and above the very top element.
- 6). Secure the sheet with L-shaped brackets and screws.
- 7). Create a radiator by bending a 3mm copper wire into an oval so that the oval is 110mm long and 18mm wide.
- 8). Create a balun by bending 8 cm of RF cable into a pear shape.
- 9). Solder the two ends of the balun and the two ends of the radiator together to the boom just under the reflector.
- 10
Stand the boom up vertically and bolt it securely to your platform. (Keep in mind the wind gusts that the antenna may have to withstand.) - 11
Connect the balun to your desired source to test the antenna.
Source...