| If you are in need of an
antenna for the lower ham radio bands that will perform good
for dx then the half square antenna may be just the ticket.
This design will require two supports at least 1/2 wave apart.
The height is not really critical as you can bend the lower
wires to fit.
This antenna is simply A dipole with 1/4 wave vertical
sections hanging on the ends. It works as two verticals fed in
phase by the top wire. This antenna does not require any
ground radials. It has A low angle of radiation making it
great for DX. The gain over a dipole is several db at low
angles, but at high angles for local work a dipole will
probably work best. It has A fairly wide pattern in two
directions along the horizontal wire)
To start figure A half wave for your band, this will be the
horizontal section. Now figure A quarter wave for the vertical
sections. Feed it at either corner directly with coax,
connecting the shield to the horizontal wire and the center to
the vertical wire.
Of corse, just as with most any antenna, the higher the
better but, If your supports are not high enough for the
vertical sections to hang without touching the ground, simply
bend them in at A few feet from the ground. This will not
degrade performance as much as you would
think. | 