Dish reflector
On Apr 16, 3:55*pm, Jim Kelley wrote:
Cecil Moore wrote:
Jim Kelley wrote:
So why do you have to go to all that trouble when you want to measure
traveling wave current, but not when you want to measure traveling
wave energy?
When one measures traveling wave energy, one
is measuring an average calculated scalar value
usually forward power minus reflected power or
RMS V*I in a dummy load resistor.
Not necessarily.
When one is measuring delay, one is measuring
instantaneous traveling wave phase in real time.
Why not just measure the delay in the instantaneous arrival of energy?
That's what pulses generators are for. *Or, simply subtract the
undesired wave from each measurement. *Search on the term 'Thruline' for
some tips on how to measure traveling waves.
Trigger on the zero crossing of the input signal
and measure the delay until the output signal
crosses zero.
That delay measurement doesn't work for standing-
wave current because the zero-crossing on the
input and output occur virtually simultaneously,
i.e. there is no relative phase shift between
input and output or between any two points on a
1/4WL wire monopole.
Flummoxed by a 'wave' which, by all accounts, does not actually exist as
such - and yet according to you it can have (or can't have, depending on
which post one reads) a phase shift or delay, whichever you prefer, and
which (according to you) has actually been quantified (3nS) by others.
It's worthy of a at least a crank.net citation if not a full article in
the Journal of Irreproducible Results. *:-)
The problem is that it's difficult to put much faith in the measurements
you report when you so badly misunderstand and mischaracterize the
measurements reported by others. *That is the only point of any of this,
Art.
ac6xg
Jim,
you were kind enough to state what the point was. Frankly that problem
applies to me
because my education was as a mechanical engineer and only a small
interest in the electrical stuff as it appeared to be all about
mathematics. What I don't understand that the argument and insults are
between Americans with the same training at American colleges
( excluding Richard ofcourse who chose literature of olde England)
Both sides should be able to understand what the other is saying! It
has been debated in earnest for several years now and all have failed
to connect.For my ideas that sort of misunderstanding is obviously my
fault and I understand that but it allows Richard to jump in with a
lack of knowledge but skilled in insults that are buried like a
crossword puzzle and his aproach to the killing fields and which many
tend to follow.Most of you are skilled engineers with a firm knowledge
of radio and yet most of you talk pass each other on the technical
subjects. One side or the other must have an understanding of the
problem so why not display it point by point in a reasonable debate so
that peace can come about?
Jim, I mean no disrespect in anyway towards you and look forward to
your posts but things have to change on this group or its
contributions to radio will come to naught.
For me a standing wave is the measurement of disparity between a
closed circuit and the period of the frequency in use and nothing
more, so all this other talk is beyond my ken
Best regards
Art
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