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This file shows 3 software programs to get all the information you need

with antenna or component
detailed Analysis.pdf

You can extract:

SWR - Standing Wave Ratio
Rs - Resistance, series form
Xs - Reactance, series form
Zmag - Impedance magnitude
Theta (deg) - Impedance angle
Rho (mag) - Reflection coefficient magnitude
RL (dB) - Return Loss, plotted as a negative number to show "reverse"
scale (see note below)
Phase (deg) - Reflection coefficient angle
% Reflected Power
Q - Quality factor, |Xs| / Rs
Rp - Resistance, parallel form
Xp - Reactance, parallel form
Ls (?H) - Equivalent inductance for series Xs, both positive and
negative
Cs (pF) - Equivalent capacitance for series Xs, both positive and
negative
Lp (?H) - Equivalent inductance for parallel Xp, both positive and
negative
Cp (pF) - Equivalent capacitance for parallel Xp, both positive and
negative

On Sat, Nov 2, 2019 at 10:46 AM, Mel Farrer, K6KBE wrote:

I have a set of SS SMA PCB mount male connectors that I soldered 4 200

ohms

0603 resistors around the clock, 12,3,6,9 and it measures very close to

my

HP SMA termination.

----------------------------------------------------------------------------------------------------------------

Mel,
I used a commercially made HP 50 ohm termination as my standard until
David Taylor pointed out that even though it was manufactured by HP its
s-parameter specs were lukewarm at best. My S11 measurements on known
devices were slightly off, but that was because my NanoVNA OSL calibration
was made with a load that was slightly off. Changing to a Mini-Circuits 50
ohm load with known s-parameter specs up to 18 GHz solved the problem. To
my point, what you have observed may not reflect accuracy unless your HP
termination is well characterized.

Of course if you are just using the NanoVNA in a hobbyist environment
where measurements within 5 - 10% are acceptable, then pretty much any 50
ohm load or termination assembled using good rf techniques should do.

- Herb

On Sat, Nov 2, 2019 at 09:56 AM, QRP RX wrote:

It looks like cheap Chinese SMA-terminators. If so, they have bad

performance.

Try to measure it with multimeter, does it have 50.0 ohm?
Most of all it has high error, something like ±5 ohm.

----------------------------------------------------------------------------------------------------------------

As QRP replied, there is a difference between a 50 ohm termination and a
good quality 50 ohm calibration load. That is why commercial calibration
kits cost so much money. Using an un-characterized termination, your OSL
calibration will look correct but you will be referencing all your
measurements to however good the termination is. For example if you use a
poor termination for performing your OSL calibration and then measure a
good quality load. The load will look poor.

Checking the termination with a multimeter only tells you what its DC
characteristics are. You need to measure the termination against a known
good quality load to verify its characteristics. It might prove worthwhile
to construct your own 50 ohm load using the methods presented by other
members of this group.

Herb

Who have used the device to measure Impedance to Common Mode Current vs
frequency for bifilar and coax wound ferrite toroid of various materials?

Interested in a step-by-step procedure, which leads tied together,
measurements shield to shield, graphic results, and perhaps pictures of
test jigs, comments on tolerance, etc.

Thanks!!

Ed McCann
AG6CX