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Rogers Corp. provides a calculator called MWI (Microwave Impedance) which I find extremely useful. You have to sign up for a free account with them (which I have had anyway). Then you can download MWI

For accurate S11 measurements of that microstrip at 1 GHz. you need a good reference plane and termination load. You can't put an SMA connector at the end of the microstrip and then use a SMA male

FR4 or XXXP is significantly cheaper than Rogers, though. There are plenty of applications where you just don't care. A microwave motion detector at 10GHz has short traces, and doesn't care what the

The calibration load -- NanoVNA Wiki: /g/nanovna-users/wiki/home NanoVNA Files: /g/nanovna-users/files Erik, PD0EK

What did you use as a load for close to 50 +j0 at 1 GHz. ?? Roger

Far end was terminated with nominal load. This was 20cm coax! -- NanoVNA Wiki: /g/nanovna-users/wiki/home NanoVNA Files: /g/nanovna-users/files Erik, PD0EK

Yes -- NanoVNA Wiki: /g/nanovna-users/wiki/home NanoVNA Files: /g/nanovna-users/files Erik, PD0EK

Good point on FR4 Er vs frequency, I forget what reasonably affordable dielectrics do! Here are a couple of simulations of microstrip: Er vs freq from

Roger & the group, I stand corrected.The Z0 does change with freq.For coax, the change is small (<5%).For Ham purposes (HF), it is negligible.For VHF & UHF, if you use quality coax (Heliax), it is

@Christian, thanks, I'll do that.

However, changing from 4.4 to 3.8 is going to show a Z change (ignoring the effects of loss, which are substantial) of sqrt(4.4/3.8) or about 7-8%. A 50 ohm line at 1 GHz would be a 54 ohm line at

Yes, that's pretty typical for lossy coax - but you're not seeing the coax's impedance changing, you're seeing the terminal impedance changing as as the coax is different numbers of wavelengths long,

Is the line terminated in the nominal impedance? or are we just seeing the reflection from the end, with loss?

Perhaps it's best to ask NanoVNA *V2* specific questions in the NanoVNA *V2* group: /g/NanoVNAV2? They make it very clear over there that "you will only get support on [that] forum".

Mike4U's comment on github: https://github.com/NanoVNA-Saver/nanovna-saver/issues/322 Indicates with the new firmware, there is a workaround by doing a little dance using the on-board set-up. IAE,

I can't help with the firmware (yet), but if NanoVNA-saver is crashing it's not the firmware causing it, it's NanoVNA-save itself (needs fixing).

I'd like to update my firmware in hopes of correcting a problem with nanovna-saver crashing with my device. In the "Version" display of my vna, it says "NanoVNA V2_2" The current firmware is

Hi Kent, nice to see you here. I have a couple of your pcb logper antennas (850-6500 MHz) that I use in my lab. Great antennas, real bargain! Tip for buyers: buy 2 of them, then you can measure the

Except for the high dollar RF materials, yes the Er of common fiberglass PCB material does change with frequency!! The Er = 4.4 measurement is made at 1000 Hz!?? Audio range. By the time you get to

Forgot the S11 plot of the bad coax -- NanoVNA Wiki: /g/nanovna-users/wiki/home NanoVNA Files: /g/nanovna-users/files Erik, PD0EK