To calculate the Z of the DUT between Ch0 and Ch1 (using S21 Series method), I initially used G3TXQ's method after converting from his formats to what the Nanovna outputs. However, I found an Agilent presentation "Challenges and Solutions for Impedance Measurements" on the web. The author described several methods including an S21 Shunt and and S21 Series method of measuring a device's impedance. I used his general formulas and converted them to run in Excel. I'll try to attach the spreadsheet.
The G3TXQ method uses an AIM brand instrument that Steve had. He did a great job of reasoning-out how to calculate the series method. The Agilent presentation gave us a better form to use and after some tinkering with the trig I was able to get the formulas to agree:)
I have good results compared against an expensive 4 terminal instrument. Please let me know how it works out for you. Thanks! 73, Pete
Sorry if some one else already posted something on this.
