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Roger, I believe DiSlord is indeed asking whether the ability to accurately measure differing DUT input and output ports would be useful. It may not be used often but there are definitely uses for

Roger, I am happy with the in/out impedances being the same. I just didn't want the renormalization feature the disappear. --John

N. I. Yannopoulou and P. E. Zimourtopoulos, "Comparing a NanoVNA with a LabVNA Part 2: Three NanoVNAs, Two H4 NanoVNAs, and One HP 8505A VNA", FunkTechnikPlus # Journal, Issue 36, Friday 31 January

Do you want different impedances on input and output? I believe that is what DiSlord is suggesting... Roger

Smith Chart is only for S11. The Port Z feature also works with S21. Roger

Nizar, I am not sure what you are saying. The existing Port Z function allows one to calculate the S parameters for another system impedance like 75 ohms. For example if a filter had a designed input

Yes NanoVNA 50Om system, but possible use math to see how this DUT measured in different impedance system For this S parameters converts to Z (DUT impedance constant and not depend from measured

Dave, The measurement is indeed made in a 50-ohm system, but given a complete (S11, S21, S22, S12) set of S-parameters in a 50 ohm system, it is possible to calculate what the S-parameters would be in

That isn't the point Dave... When converting back to real values, whether the center 1 represents 50 Ohms or something else makes a difference. Or have I got something wrong here?

But the measurement system - that of the NANOVNA - is always in a 50-ohm system. To do it correctly, matching networks are required to match anything other than 50-ohms. Dave - W?LEV

Roger, The renormalization is useful for measuring networks (like crystal or ceramic filters) which are designed for other impedance levels. For example, it allows you to evaluate a 10.7MHz, 330ohm

There are quite a number of cheap and useful signal generators offered on epay. Dave - W?LEV

HI Philip tnx for the advice. I use a combo of SMA M/F attenuators to stay well under +10dBm max signal level for NanoVNA input. Wonder if you too use FY 6XXX generator. Gabriele, I4JXE

Hi Roger If the coding does not require a huge complication nor a large resources, it would be appreciated to have this option of the Z port2, it would also approach the enhanced response on H4

The 250m is a scaling parameter on the grid . So each successive horizontal line for SWR, in this case, increases by .25. 1.891 is the SWR calculated at the marker. Go into the Display/Scale menu to

DiSlord, I have tested your port renormalization function (called Port Z) for several values of Z like 75 and 100 ohms. It calculated S11 and S21 correctly for DUT's

Hi DiSlord and All I already used the standard load= 50.83 Ohm ( DC measur by a good Multimeter's) instead of 50.00 Ohm for the Nano calibration, and a Z0= 78.9 Ohm to optimise my nominal 75 Ohm coax

VNA calibrated by 50Om - nominal port impedance On measure S parameters possible calculate get Z parameters (by known Z0 = 50) Next possible calculate from this Z new S` parameters but use Z` != 50 Om

Yes, but I believe anyone (well........."maybe") can multiply any number by unity: 1. Or maybe not??????? Even with a normalized chart center, the measurement system is still as close to 50 ± j 0 as

Isn't that what the Z function does--allow normalisation of the chart to any resistance?