In message , amdx
writes
I'm about to install a 125 ft long antenna 30 ft high.
Is there any advantage to bringing the far end back
down to the ground or near the ground.
What does this extra wire do to the impedance?
Pattern?

It will probably lower the various 'natural' resonant frequencies a
little, and also change the angles and directions of signal pickup.
However, I don't think that you're unlikely to notice much difference.

If you do want to bring the far end down to ground level, you might like
to consider the potential reduction of local noise by inserting a
(typically) 9:1 impedance transformer and far end ground, and bringing
the RF signal back to the house via coax.
--
Ian