20 meter quarter-wave vertical antenna experiment

Not content with attempting to understand and build 40 and 80 meter verticals, I’ve decided to build a 20 meter version tonight. This has 4 x sloping radials at 45 degrees with a feedpojnt up at about 7 meters in the air. On receive, it’s actually pretty good; only for extremely weak or barely readable signals is it beaten by the 40m loop or my attic mounted half-sized G5RV.

For the record, it performed straight out the box with dimensions of a whisker under 5 meters for both radiator and radials.

Picture below shows typical far-field plot for a quarter-wave vertical.