Dualband portable 2 elements yagi antenna for 10m and 15m CW. The idea behind it is simple; We construct a 2-elements Yagi antenna for 15m band, then add 10m band 2 elements yagi into it so the driven element for the 10m band is open-sleeve-coupled from the 15m band driven element. This method of feeding will results of an easy-to-construct-and-feed dualband yagi antenna at the expense of narrower bandwidth at the higher band. The narrower bandwidth is not a problem since the usage at 10m band is intended for CW portion only.
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Tuning procedure:
- Mount the antenna at the real installation height, or at least 7 m above the ground.
- Tune the 15 m band driven element for the lowest VSWR at 21.05 MHz. Adjust both end simultaneously.
- Tune the 10 m band driven element for the lowest VSWR at 28.05 MHz. Adjust both end simultaneously.
- Back to 15 m band and check if whether the VSWR shift after 10 m band tuning. If so, then re-adjust the 15 m band driven element.
- Again, back to 10 m band and check again. Repeat this procedure until VSWR is satifying at both band.
Typical VSWR:
- 15m band; 1.04:1 at 21.05 MHz
- 10m band; 1.12:1 at 28.05 MHz
Typical gain:
- 15m band (10 m above ground); 11.5 dBi
- 10m band (10 m above ground); 12.4 dBi
15m band at 9 UTC
10m band at 11 UTC
- Fork it https://github.com/handiko/Portable-Yagi-10-15-2E/fork
- Create new branch (
git checkout -b myfeature) - Do some editing / create new feature
- Commit your works (
git commit -m "Adding some myfeature blah blah..") - Push to the branch (
git push -u origin myfeature) - Create a new Pull Request