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You did not get power correctly :) P=Vrms^2/R, so if you have Vpp=175V (peak to peak), Vmax=Vpp/2=87.5V and Vrms=Vmax/sqrt2=87.5/1.41=62V and P=77W on 50ohm load

Hi, Thanks for the clarification, do you think this is due to the PVC itself absorbing water, or just moisture in the air? 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL

Yes - I think probably more due to porosity and filler than the actual PVC itself. If you go look up a plastics table, PVC is in the "generally non-hygroscopic" bucket (like PE, PP and PS) However, in

Ed, if you have S21 in terms of magnitude and phase, calculation of the series impedance of the device being measured is straight forward: Zdut = Zo*((2/S21) - 2), where Zo = 50 ohms for a 50-ohm VNC.

I am referring to the line: "It's also fairly hygroscopic..." Is this referring to PVC? 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL

Jim, it was quite interesting to watch the PVC-wound CMC 'do its thing'. I certainly didn't need 2.4 GHz, just 40-meters at 400-watts. It was really rather fascinating to watch the SWR climb with

yes, it's kind of like nylon in that way, and unlike, say polyethylene, PTFE, or polypropylene, which "as delivered" tend to be fairly hydrophobic. From what I understand, depending on what kind of

Are you referring to PVC here? 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL Asst. Director, NW Division, Technical Resources

PVC has a low melting/softening point, so it's sensitive to these kinds of effects. It's also fairly hygroscopic, but I doubt mois

Great! ...Larry

Sucess !!! Thanks Larry, I downloaded 1.0.45, and followed the same steps I did before and it loaded fine with the original DFU app....somehow the 1.0.39 must have been kludged somewhere....

Very nice compilation! So what is up with the PVC insulation? I know that PVC is particularly bad in terms of dissipation factor - but is it insulation self heating or just getting melted by a hot

Many thanks for the link to that document... I just ordered a NanoVNA, and am getting ready for it. 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist,

For a different perspective, G3TXQ's Common-mode Choke webpage discusses why reactive (e.g. inductive) common-mode chokes are undesirable, and he gives an example of an inductive common-mode choke

Jamie, I think you've overwritten the existing copy with a dump from your device. Delete the firmware you're trying to update with and get a new copy from the files section of the forum - use 1.0.45

Yea, tried that, no joy....followed the W2AEW YouTube video ( mine is exactly like his), works great, until I restart, still says 0.5.0.....I’m going to try Larry’s modified GUI next....thanks...l

Jamie, It's in the Misc folder: /g/nanovna-users/files/Miscellaneous Rename the original defuse.exe to defuse.orig.exe and then drop in the modified one - there are two: One with

See Absolute_Beginner_Guide_NanoVNA_v1_6.pdf, page 49. The PDF file is in the file section . 73 Martin 9A2JK

Ed, unfortunately I did not measure that parameter. Most of the readers are just interested in dB attenuation so I didn't measure the complex impedance. However, the inductance of the CMC is

Great work Dave. Thanks for your continuing contribution to our great hobby. Do you have in your stash a piece on conversion of dB attenuation to Zs= Rs + Xs ? 73, Ed McCann AG6CX