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#103 : The Fourth Load *

Dear all,

Yes, indeed !

- - - - - - - - - - - - - (c) gin&pez@arg (cc-by-4.0) 2019 : start - - - - - - - - - - -

It seems that the ratio of these two cross-ratios, the one of the loads and the
other one of their corresponding measurements, is equal to the constant (1,0).

But in fact, the origins of these two cross ratios are obviously different for
The Common User, who connects exterior loads to his VNA to get the
corresponding interior measurements from it - that is very different, indeed.

The trick, that convinces The Common User (who is an unsuspected one,
an innocent enough), has to do with two imperceptible leaps, from practice
to theory and then back to practice again, as follows:

(1) In Practice : The Common User (who is an unsuspected one, an innocent
enough), connects 3 loads, which he believes, instead of he prays-hopes-thinks
but finally just * l i k e s *, that are of a well defined known value (and perhaps
of uncertainty), that is a so called a standard one : S, L, O, as well as, he also
connects The Fourth Load, an unknown one, so that his VNA shows to him
their corresponding four 4 measurements : s, l, o, g, which in this way are all
* i n d e e d * known, then

(2) In Theory : The corresponding value of The Fourth Load, that is the one which
The Common User (who is an unsuspected one, an innocent enough), he * l i k e s *
to consider it as the only one unknown, is * c o m p u t e d *, either by his VNA
itself or by his one hand, by using the * t h e o r e t i c a l * a b s o l u t e * equality
of this ratio of these two cross-ratios (but of their very different origins, the one
from the loads and the other one from their corresponding measurements) to the
constant (1,0), and finally again

(3) Back in Practice : It is exactly this * t h e o r e t i c a l * value of The Fourth Load,
that The Common User (who is an unsuspected one, an innocent enough), he
* l i k e s * to take it for granted.

- - - - - - - - - - - - - finish : (c) gin&pez@arg (cc-by-4.0) 2019 - - - - - - - - - - -

Sincerely,

gin&pez@arg

*
#102: The Complete "Demystification" of the "VNA Measurements" Kind - Farewell
/g/nanovna-users/message/9073

:103#