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Where does the original poster say anything about the "measure cable:" function? The NanoVNA has an "SWR" function. I use it quite a bit. Zack W9SZ

it does not send a pulse - what it does is sweep a range of frequencies, and then mathematically transforms the measurement to what it would have been if it were a pulse (or step).

BUT with the 'measure cable' function, you cannot specify a frequency, and the function is not intended or designed to measure frequency (it sends a pulse, not a sweep) or measure SWR. MEASURE CABLE

This is true of most switch topologies. Another frequency-dependent characteristic of mechanical switches which can crop up during testing, especially in the microwave region, is resonances from

** Yes, it is used to measure the length of a real cable :). In your case, you are not measuring a cable but an antenna connected to the end of a cable. When only one port is used, the nanoVNA only

The "measure cable" function was designed to measure a transmission line (e.g. length of coax), open at the far end, and give you its characteristic impedance, loss, and length (length only when you

Steve, The nano is measuring only the cable length, not the antenna plus cable. Gary W9TD

My NanoVNA shows a single wire length (when measuring cable) for the fan dipole even though there are definitely multiple lengths of wire (all different) in the air. This length stays the same as I

What DFU software are you using? There are four programs for installing firmware updates that I know about. The original one from ST, Dfuse Demo, works well on older computers but refuses to connect

Hello All, I cannot for some reason get my H4 into DFU mode on my laptop; I don't have a problem with my desktop computer (running the same version of NanoVNA App). Is there something that I should be

Log mag S21 is what I use, and yes, typically quite frequency dependent for switches based on non-RF relays (i.e. most amateur switch boxes). The leakage is mostly due to parasitic C, so the leakage

Thanks Jim. Still learning this neat tool. So just the phase trace is all thats needed on s21 to measure isolation? Are results frequency dependent? Bryan, n0luf

Don't do "double calibration", it just forces the device to do interpolation between points. The note in documentation remains there for misbehaving devices that would give out or range values when

Thanks for all of the help. The plots are very enlightening. it seems like this explains this. In response to the on device calibration, is disabling it simply unchecking the apply button? And also

If you do not have the version 0.8 as *.bin (or *.dfu) file I would propose to save it from device before you flash the new version. Dunno how to do it on windows, on linux I use "dfu-util -d

Saa2n has a custom display pcb... So you must buy a "normal" 4 inch display and desolder the flatband cable (if display screen is broken)... Or you must ask the seller to send you a display (if it is

0.8 is an extremely old version. This should work on your device: https://github.com/DiSlord/NanoVNA-D/releases/download/v1.2.20/NanoVNA.H.v1.2.20.dfu In case you were worried about "bricking" your

I have an SAA 2 4 in nano VNA and I need a new screen any place available to buy a 4-in screen De K8HTB Joe

Measuring switch isolation. Let's say your switch has a common, and 4 switched outputs A,B,C,D Hook the VNA up to Ch0 to A and Ch1 to B, put a load on Common, set the switch to A, and measure the S21.

I've done similar with antenna analyzers in the past and currently with a VNA. Switches I've used provided sufficient isolation...so far.