View Single Post
  #166   Report Post  
Old April 12th 07, 01:15 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
external usenet poster
 
First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default Constructive interference in radiowave propagation

Keith Dysart wrote:
My mistake. But it is difficult to know your position when
you don't indicate clearly that you disagree, so I thought
that with your reply you were agreeing. Apologies.


I don't disagree with anyone's metaphysics. What
you do inside your own mind is none of my business.
(In my mind, I can still dunk a basketball.)

This is a bit of a non sequitur. So what is it that you really
disagree with in the analyses performed by myself and others?


I have told you many times. Bench test measurements
performed over the past 20 years or so prove that it
works only in your mind, not in reality. The source
impedance of a typical ham transmitter remains somewhat
of a mystery during actual operation. The arguments
continue to rage after decades of bench test experiments
and measurements. The pages of QEX are filled with those
arguments.

A generator with a 450 Ohm source impedance ...


False assumption. That transmitters's source impedance
changes away from 450 ohms just as soon as the reflections
arrive incident upon the source, i.e. the source impedance
is a *variable* that depends upon the magnitude and phase
of the reflected wave. If your source impedance is constant,
it doesn't match real-world conditions.

I think you object to computing the amount of the reverse wave
that is reflected at the generator by using the source impedance.


I certainly don't object to your computations but the
results of those computations have been disproved on
the bench using real world ham transmitters over the
past 20 years or so. Your simple mental model doesn't
correspond to reality unless you take some extraordinary
steps which deviate from real-world ham transmitters.
Have you taken the time to review those experiments?
--
73, Cecil http://www.w5dxp.com