I take your point, but I feel that for many purposes start and stop frequencies are all you need to change, perhaps followed by a calibration. I guess the TDR measurements (find a cable length or a fa

A NanoVNA is the wrong device for that task. Purchasing a TinySA Ultra would be my first step: https://tinysa.org/wiki/pmwiki.php?n=Main.Buying Only use the approved suppliers listed there. Cheers, Da

Dean, It's because any changes in the program may, by chance, create a pattern which resembles part of a known virus. That's why I recommended running the file past a couple of trusted scanners (URL i

It's fine here, Mike, Windows-10 + Windows anti-virus. Suggest checking on Jotti or Virus Total. https://virusscan.jotti.org/ https://www.virustotal.com/gui/home/upload 73, David GM8ARV -- SatSignal S

Sam, Yes, but you can buy a replacement set very cheaply. To a degree, the quality will be determined by how much you pay, but perhaps search Amazon for: sma calibration About US $15. 73, David GM8ARV

Sorry, but that info is for the LiteVNA. Still worth the red-light check, though. David -- SatSignal Software - Quality software for you Web: https://www.satsignal.eu Email: davidtaylor@... Tw

The H4 has the unfortunate habit of discharging it's battery even when not is use. Try leaving it attached to a charger (or PC port) for an extended period. Does the red charge light come on? 73, Davi

Dave, It /might/ be exactly the same, but with the H rather than the H4 firmware. The H firmware is actually included in the NanoVNA-App. https://github.com/DiSlord/NanoVNA-App/tree/33cded170426c3c48f

I think this is where we differ. A VSWR of 3:1 will have identical S parameters whether it be in a 50- or 75-ohm system. Half the power being reflected is what matters in a system and whatever the con

Again, it's a ratio, not an impedance! David -- SatSignal Software - Quality software for you Web: https://www.satsignal.eu Email: davidtaylor@... Twitter: @gm8arv

... and if that system is 75-ohm rather than 50-ohm? The S11 is a ratio expressed as a complex number, not an impedance itself. David -- SatSignal Software - Quality software for you Web: https://www.

I don't see how S21 (for example) is an impedance. David -- SatSignal Software - Quality software for you Web: https://www.satsignal.eu Email: davidtaylor@... Twitter: @gm8arv

Both, I have a similar one (but not quite identical) to that which Burt listed, and I've been pleased with mine. 73, David GM8ARV -- SatSignal Software - Quality software for you Web: https://www.sats

I have installed and shown no errors with very brief testing. My hope is that any earlier errors have been fixed, but my concern is what new errors may have been introduced! You can always reprogram t

Who was Maya? David -- SatSignal Software - Quality software for you Web: https://www.satsignal.eu Email: davidtaylor@... Twitter: @gm8arv

There are some videos - Google "nanvna crystal filters". For example these two videos use the H4. https://www.youtube.com/watch?v=G9zZRNzhsEE https://www.youtube.com/watch?v=NVigVbwwvPQ I think there

Rasoul, I hear that for crystal filter measurements you may need the H4 VNA, as the other interrupt the signal making the response ambiguous. Your matching arrangement may need attention, too. Cheers,

Mike, 150 dB per division! Why not measure S21 through (with a cable connection) /after/ calibration using a range of +2..-8dB, at a scale of 1 dB/division? Any noise floor jump is likely due to harmo

Mark, My H4 bought in January this year (2023) from an official source in the UK /does/ have an SD slot and card within. The serial number does /not/ start "AA". It cost about GBP 80+post. I have been

I can recommend H2TestW as well: https://www.heise.de/download/product/h2testw-50539 It works in English as well as German. Cheers, David -- SatSignal Software - Quality software for you Web: https://