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Because the FET is not really switching things at the RF rate, the gate being DC biased; the channel is just being opened or closed by the gate and looks like a bias-dependent resistor (plus all of

It's not a circuit model, just an arbitrary number to allow comparing switches. The linked articles talk more about the theory.

Yep, that's the next on my list :) This is interesting value, will need to read a bit more, appears to represent N channel as RC comprised of Coff and Ron

I've used a lot of MMIC FET switches over the years, but not actually designed them, so I can't speak to "bandwidth of the part" vs "bandwidth of the switch". I'm going to guess, based

Let's say that my use case is the one where "cross channel leakage" and "off isolation" are not overly critical (HF antenna switching). The biasing - to be honest, in my "thought experiment" I

Fair point - my use case is more forgiving - I'm "exploring" options to replace relay based HF antenna switch, where "OFF isolation" is marginally critical. But back to "academical" side of the

Brent, see this topic. It shows the jig I used to measure the ferrite beads: /g/nanovna-users/topic/79953788#20089 But I calibrated it with a 50? SMD resistor, rather than the

Thank you Roger Here's why it seemed to connect at low level and then it didn't work anymore. So that solves my notice problem :( -- F1AMM (Fran?ois)

NanoVNA-F is not compatible with NanoVNA App because the -F does not use a binary transfer protocol. Roger

That will be the challenge - off isolation. (and the usual issues with biasing, just like using diodes as switches) You might look at T/R switch literature - It's a similar problem - slow switching,

Miro, Even if we assume that you can bias the MOSFET properly in the presence of RF and try to use it as a switch, and even if we assume that it behaves pretty well in the ON state given its pretty

OK, this one is only artificially aligned with this group buy using NanoVNA to actually measure what I expect to be answered in a more "academic" fashion :) How does MOSFET behaves in the triode

https://nanovna.com/?page_id=141 :) -- F1AMM Fran?ois

Can someone provide the link to pre compiled version of NanoVNA-App for Windows - link provided here https://nanovna.com/?page_id=141 does not work, and github page only offers source so one can

Thanks The url does not point to a use of the nanoVNA-App software I have "COM9" which is displayed and Connected/Disconnected which switches. If I click "Calibration", [Click to open Calibration

Roger Thanks for the annotated screen shot. Very helpful. I am a newbie, lying in the weeds observing what is going on. I have made a copy of your post for future reference. Thanks again. Don KC3MPO

Yes. I agree, R&S has published some very good information. My current questions revolve, very specifically, around fixturing and calibration for measuring "soft" ferrites, of which there is much less

Attached is a description of what all the buttons are used for. You right click on a graph for more options. This is a link to a previous discussion in this group about NanoVNA App

Fran?ois, you can easily learn to use NanoVNA App by the good old tried method of clicking on each icon and seeing what it does! The one thing you need to know is to right-click on the graph, to get

** Thanks. It's pretty but I don't understand this software at all. It runs on my Windows Seven. Is there a notice? I'm like a chicken that just found a knife :). I use nanaovana-saver which I think I