open - short -- 0 - 180 ??
Cecil,
Thanks for the pointer. I split the sweep signal input and fed the
analyzer with 'in phase' signals. I then set the analyzer phase to a
known reading, line on the phase display. I then tested this by
comparing it to short and open. It was almost identical to the short
reading, less then about 4% difference.
This is being used to analyze a loaded dipole without any input network.
With above setup the antenna is now reading 'inductive' which is
consistent for this network.
The next step is to determine the amount of capacitance to bring the
reflection to 0j at the frequency of interest. This could result in a
reading of 0 or +/-180 degrees phase. If it is 0 then the impedance is
less then 50 Ohms, if it is 180 then the impedance is greater the 50 Ohms.
Thanks - Dan
Cecil Moore wrote:
dansawyeror wrote:
The detectors are classified as power detectors. What effect would
that have?
Power is a scalar and doesn't have a phase. If phase
is required in a power equation, it is normally the
phase between the associated voltages, e.g. the phase
used in the interference term in the irradiance equation
in optics is the phase between the (visible) E-fields.
I would assume the power detector phase convention would
be the same as in optics, but I'm not absolutely sure.
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