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Old March 15th 07, 10:40 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Windom antennas - down to earth

On Thu, 15 Mar 2007 15:57:50 -0400, Michael Coslo
wrote:

On Thu, 08 Mar 2007 08:03:56 -0800, Richard Clark
wrote:
Coming in late, did I miss someone's extravagant claim that a OCF
could do better?


The idea that an OCF is superior to a dipole, and certainly Richard's
statements would indicate that; makes me wonder why everyone isn't using
them!


Hi Mike,

With all the intervening comments removed, want to reconsider that
again?

An OCF is simply resonant at exactly (by modeling) the same points as
the dipole of the same length. Resonance resides in the wire, not the
drive point. Of Course, F***! (expletive deleted to explain the
meaning of OCF) as the drivepoint is moved through the length, its
fundamental Z (still real) varies from low (at midpoint) to high (near
endpoint) in much the same manner as we would expect for the
difference between a conventional halfwave dipole and conventional
halfwave end-fed. The harmonic drivepoint Zs follow their own
sinusoidal roller coaster through the shift in feed point.

73's
Richard Clark, KB7QHC