This Windows program plots S-parameters for one or two Touchstone files. For component measurement, it plots Z, L, Q, C, DF, and ESR using the S11 reflection, Y21 series-through, S21 series-through, and S21 shunt-through methods. The Y21 method suppresses stray reactance. The program displays wrapped or unwrapped phase, filtered or unfiltered group delay, file comments, and file data.
You can renormalize the reference impedance. It can differ for each VNA port and can include shunt capacitance. Renormalization lets you measure a device at 50 ohms and plot the response at its design impedance. No matching network is needed.
This plot compares insertion loss for two winding techniques for a 1:49 ferrite transformer, the kind used with an end-fed halfwave antenna. Both port impedances have been renormalized.
SWR for the transformers. Adjust the primary capacitance to minimize insertion loss and SWR. Vary the primary resistance to simulate an antenna tuner and the secondary resistance to simulate antenna variation.
Unwrapping crystal filter phase.
88–108 MHz