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Kadir, Please do not post messages on this forum that contain only marketing information that is not specifically related to the NanoVNA product concerned with this particular group. I have deleted

Yes!!! Learn the Smith Chart!!!! Also, learn and internalize Ohm's Law!!!! Both will serve you well with all things RF. SWR can be measured as current, or voltage standing wave ratios. A good test for

Helpful document: https://www.maximintegrated.com/en/design/technical-documents/tutorials/5/5432.html

Russ, If the load is not perfectly matched to the source, there will be a voltage standing wave ratio (VSWR) because of the mismatch. Learn the Smith chart.

SWR = Zt / Zo applies only when both impedances are resistive. When Zt = 40 + j30 ohms, the load is highly reactive. The coefficient of reflection rho is: rho = (Zt - Zo) / (Zt + Zo) = 0 + j0.3333 ...

Can you explain this in more detail. I thought VSWR was based on voltage.

40+j30 is a Z of 50 ohms. In this case, this is an SWR 1:2 !!! Not 1:1 . Only swr 1:1 is 50 ohms resistive load (and then again, using a 50 ohm cable ;-) ). 73 Arie PA3A Op 3-8-2022 om 02:26 schreef

Incorrect. The VSWR is based on impedance - which is a combination of resistance and reactance. A vertical at resonance will have an impedance of about 35 + 0j ohms or an impedance of 35 ohms and a

Note that when the load looks resistive the VSWR versus frequency is at a minimum.

And please remember resonance is not necessarily at 1:1 SWR. It may or may not be. Resonance is *defined* by (consult the complex portion of the measured impedance): +jX = -jX. The resistance term is

In my Excel file, it is not about calibration but about measurements. The calibration has been done and has been corrected /g/nanovna-users/message/29103 The calibration file shows

I seldom calibrate the VNA with nanosaver, so really cannot tell how that one works out for me. Nor is my VNA (Now a H4.3) the same as F1AMM's. So I cannot compare. (I read somewhere that Fran?ois

Hello Here is the test I did Measurements on a loop antenna at a distance of 50 m (zero reagent around 7.100 MHz) between 1 and 20 MHz (1010 steps or 10 segments) made with a nanaoVNA-F and

why not just calibrate at the cable end?? much easier as messing with the long delay ... not?!? dg9bfc sigi ps did you check open and short (with cable!!)?!?!? Am 01.08.2022 um 14:40 schrieb Diane

I agree with you. Using edelay to de-embed a coaxial cable is not a good idea if impedance measurements are the goal. The attenuation of the cable affects the measurement. Things get worse the higher

Hello, Thanks, everyone for your tips. Finally, this is what I've done. Best regards

Hello, Thanks for your reply. I am using a quarter wavelength antenna. Best regards

You should better calibrate at the cable end and NOT on the vna.. No circles anymore!! Nothing to compensate via edelay.. I only use edelay to compensate say an sma to n adaptor.. But not to

Hello Roger, Thanks for reminding me, I will post on the other topic how I went about correcting the electronic delay introduced by the SMA cable. My cable was too long to correct the electronic delay

** No, the "clicks" are never in the same place. We will say, to simplify, that it is parasites that cause this. We find the same thing in the .S1p files but it's less troublesome. If I want data