The operating frequency. It should work adequately over a single band,
but not multiple bands. At frequencies near, but not exactly at, the
frequency you've cut the feedlines for, the effect will be that a little
reactance will appear at the point where the unused feedline connects.
This will make the antenna tune a little differently, but have no other
significant effect. Far away from that frequency, though, as on another
band, you can have some wild impedances at the second feedline
connection point, resulting in a very different pattern and impedance at
the active feedpoint.

Roy Lewallen, W7EL

T.E.O wrote:
Roy

Tnx for the reply. Is the 1/4 or 1/2 wl feed line you desribe measured using
the fundamental (1wl) freq. of the loop or the operating freq.?

Terry
W8EJO