Thread: Dish reflector
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Old April 23rd 09, 05:26 PM posted to rec.radio.amateur.antenna
steveeh131047 steveeh131047 is offline
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Default Loading coils: was Dish reflector

On Apr 23, 4:42*pm, Jim Kelley wrote:

For a more quantitative illustration of how distributed reactance in
transmission lines causes delay seehttp://www.rhombus-ind.com/dlcat/app1_pas.pdf

73, ac6xg


Jim, thanks for the reference.

Perhaps I should have expressed myself more clearly. What I've not
seen, for example, is a lumped-element analysis which takes just the
coil dimensions as input, and predicts theoretically - without a lot
of empirical "tweaking" - the reactance at a particular frequency;
particularly a frequency close to self-resonance. There may be one out
there, but I've not yet found it!

In contrast, the ON4AA calculator - based on Corums' transmission-line
analysis - does just that, and produces results which seem to match
well the EZNEC modelling results.

Regards,
Steve G3TXQ