A delta loop is an antenna for the low bands that has vertical polarization but
does not need a good ground. An equilateral triangle, apex up, fed 1/4
wavelength from the top, will give vertical polarization. The bottom leg of the
delta loop can be only a few feet off the ground, and it provides the 'ground
return' for the antenna. The impedance of a single loop is around 100 ohms and
can be matched with an electrical quarter wave of 75 ohm coax.
A pair of delta loops can be phased for gain similar to a four-square. I have
this antenna for 80 meters with no radials on the ground. Guest ops always
remark about how well it plays.
-Tony, K1KP
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