On Mon, 15 Dec 2008 21:50:04 GMT, Owen Duffy wrote:

Richard Clark wrote in
:

I am wondering why you are trying to resurrect this train wreck.

I was seeking comment on the issue of asymetric branch feed topology.

Hi Owen,

That seemed to be a strain based on the illustration offered as it
wanders the field.

It was put to me that accounting for the phase shift due to the different
branch lengths does not fully account for the time lag. My contention is
that in transforming the problem to the frequency domain, conversion of
time lag to phase lag fully and properly accounts for the different
branch lengths.

Too many conversions going on there in your statement. I don't see
any transformation (conversion?) to OR from the frequency domain; and
I don't see what that would offer. Distance, "polarity," phase and
time are all hands on the same watch. Their conversion is trivial -
as you appear to be rebutting to your critic.

Gordon's paper was offered as evidence that my feed was "WRONG!".

The offeror left it you to sort it out rather than arguing their own
case, hmm?

Yesterday, I note that Kraus has a clear diagram of branch vs distributed
feed, and the technique of transposition to offset a half wave phase
delay.

I also note the ARRL agrees with me (http://www.vk1od.net/lost/Fig7.png
(c)), but that isn't a bullet proof recommendation!

True.

I am now confident my critic was wrong.

If the criticism is, as you offer above about accounting for "time
lag," as if that fell into some special category, then your confidence
is well grounded.

When I examine your other correspondence to piece together the story,
then both sides of the argument have valid points. Yours, being more
general, is more conclusive.

The second take-home here seems to be, if you wish to teach someone
how to perform a task, or build a project, you shouldn't do it with
negative examples without being encyclopedic to completion (which
invites boredom).

A proof with the free version of EZNEC was easily achieved with some
minor elaborations for the NBS Yagi. That is the beauty of modeling,
it encompasses ALL the ways to fail or succeed.

73's
Richard Clark, KB7QHC