Richard Harrison wrote:
Cecil, W5DXP wrote:
"I suapect they (reflections) are originating at the feedpoint, i.e. the
forward wave travels all the way around the loop and is reflected from
the impedance discontinuity at the feedpoint."

That would be a reflection from a virtual impedance bump wouldn`t it?

No, the impedance bump is physical. The physical Z0 of the
feedline is no doubt different from the physical Z0 of the
loop.

The wave travels both wires of a feedline simultaneously, and enters
both ends of the loop at the same time. The collision is at the midpoint
of the loop opposite the feedpoint.

Waves traveling in opposite directions in a constant Z0
environment don't interact. If the Z0 doesn't change, they
pass each other "like ships in the night".

Arnold B. Bailey says on page 399 of "TV and Other Receiving Antennas":
"Now, in the loop, the far-end reflection point is a short circuit, and
hence, the current is high at this far end."

If there is no physical impedance discontinuity, there is
no reflection. Reflections occur only at physical impedance
discontinuities. That virtual short circuit is an effect,
not a cause.
--
73, Cecil http://www.w5dxp.com