Equi is for equal, libra is the sign of Zodiac which is a pair of
scales

It means that a repetitive action must come back to its source.
AC power has a cycle as in frequency, thus its circuit is one
wavelength.

A quad antenna represents a one wave circuit where total length is
proportionat
to time .ie a picture of events during one cycle.
Now place along side of the quad a radiator of your choice where
the length of the short radiator is superimposed upon the quad.
For ease in foillowing the electrical circuit make your shorty
antenna
equal to one side of the quad

So the race begins. Both travel up for a time at the SAME velocity.
At the corner of the quad power travels onward until it gets to its
originating point to complete a cycle
The short antenna appears to have nowhere to go so what does it do?
To duplicate the quad action it must have a circuit of some sort where
the power can still travel forward during the time the power in the
quad
is still travelling to the originating point.

Complete the circuit of the short antenna showing the series of events
that occur upto the point that the events on the quad come to its
point of beginning.

Note The impedance of space is 377 ohms, the impedance of ground can
be your choice.
Art