... Below 300MHz, the original NanoVNA offers some advantages I have yet to see matched.
hello joeqsmith,
you mention that over low frequencies, the nanoVNA is OK.
I have a nanoVNA-H4, I confirm that point, when I just want to see the self resonant freq of a MLCC X7R (sorry for this basic example :-) )
Recently I get bored to wait for the nanoVNA to sweeeeeeeep (too long), so I bought a LibreVNA => much faster ! Cool ! The LibreVNA freeware : top cool too (requires some time to understand the features but... top ! )
Problem : when I tested a basic X7R, having a SRF @ 300kHz => the LibreVNA was blind vs its SRF due a too high noise (wavvy curve around magnitude=-40dB) over the weird frequency range : mini 100kHz to 1.29Mhz, then, the measurement was in line with the product characteristics (strange).
Is it a common drawback of LibreVNA & others (except the nano) to struggle to do clean measurements over the low-end frequencies ? or if my vendor replaces my LibreVNA by a new one, I'll have no issue ? (a bad item, it can happen) ; I'm waiting for feedback from him, he's waiting for feedback from the manufacturer...)
After reading this thread & the other in link above, I'm a bit confused to discover that the ability of VNAs to do clean measurements over low frequencies is "tricky".
Fortunatly, my nanoVNA does the job. But it is so slow...
When I look at the other VNAs on the market, I end up to the conclusion that, regarding low freq measurements, we have (vs price) : the nanoVNA (100eur) and then... the cheapest seems to be the Siglent SNA5002A (8000eur). What a gap ! :-)