The half square is really a Bob tail array. W6BCX was the inventor. A W8
decided to feed the antenna at the current point (top) rather than the
bottom which requires a complex matching circuit. Jim West at Antennas West
sold the devil out of the antenna. The coax feed must be at near right
angles to the down side to avoid problems.
The Bob tail or the 3 el Bob Tail we see in say the Editors and Engineers
Handbook is a broadside antenna with about 4 to 7 Dbi gain (not DBD).
Not a bad antenna for 20 or even 40 if you can l live with two directions.
There was a QST article on mounting two in an L config to give you all four
directions but even with 40 you need an acre and plenty of tall trees at the
right places.
Dave K4JRB
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