On 6/27/21 10:36 AM, Jim Cotton via groups.io wrote:
I paid more for a good used HP 85032B N calibration kit for my 8702B than for the LibreVNA.
The LibreVNA has a spectacular price performance ratio and decent specifications to 3GHz, 3-6 GHz is a bonus and it certainly works well enough to be useful.
The software V1.1.2 with firmware 5 is usable if not full featured.
What tests would one choose to compare VNA'S?? Sweep a filter, impedance match a device, measure cable length, ...?
I suspect the majority of NanoVNA users use them at HF unless testing antennas...
Jimn8qoh
Stuff you can do with some VNAs
sweep a filter with many sections and narrow bandwidth (i.e. lots of envelope delay)
sweep a crystal (sort of like above)
testing an amplifier
looking for a "small" mismatch in a long cable (i.e. put a tiny mismatch 10 meters from the end of a 30 meter cable with a fairly good load) with synthetic TDR
measuring transformers and extracting parameters, particularly in a 4 port scenario (i.e. a transformer with two center tapped windings)
measuring impedances that are a LONG way from 50 ohms (i.e. measuring small changes in reflection coefficient near 1)
measuring mixers (lots of ways to do this with a two port analyzer)
Some of this is more about calibration and stability than the raw SNR performance
