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I have been dealing with this since the last upgrade. I do not have this issue with NanoVNA by eddy555. It is quite annoying but harmless. Jim Barber KJ7JGB Phone: 503.547.9524

An interesting discussion about lead inductance and shunt capacitance of carbon composition, carbon film and high wattage carbon resistors in this article by Bob Botos of HP.

http://jeroen.web.cern.ch/jeroen/resistor/shuntC.html

There is possibly even more important effect - nanoVNE does NOT measure impedance as an absolute value - it compares the current one with what you have declared as 50+j0 at the time of calibration. If

High value resistors will become capacitive at high frequencies, while low value ones will become inductive. Both the series inductance and the parallel capacitance of a resistor will of course have

Yes. Replacing those defaults in VNA.py fixes it... # return 27000000, 30000000 return 1000000, 100000000 Of course this is just a bodge! Looks like this is a NanoVNA-Saver problem. I will investigate

Try measuring higher resistance carbon resistors at RF. The shunt C of somewhere under 1 pF becomes the issue as frequency is increased. My first investigation into this was with the ancient

Sure.. Hook it up and see if it presents a reasonable match (uncalibrated, even) SMA terminations or SMA loads.

Maybe, maybe not - 50 ohms is a low resistance. They cost pennies, if you have one, hook it up directly to the NanoVNA and see.? You could solder it to a SMA jack and use a barrel to connect it. Chip

A long time ago I spent too much time going around just getting the part. They cost more back then when money wasn't worth a lot. Recently I needed an attenuator and went to Amazon. They seem to have

Official name SMA connectors. https://www.ebay.com/sch/i.html?_from=R40&_nkw=miniature+SMA+coaxial+connectors+termination+load+50+Ohms&_sacat=0&rt=nc&LH_FS=1 Please note how many are being

https://www.amazon.com/gp/product/B08N4DHJHS 73, Willie N1JBJ

OK, I will freely admit I have no clue where I put the ones which came with the unit. Secondly - I am not looking to measure stuff to 3 decimal points precision - I just want to see the "resonant

For HF frequencies the effect of resistor lead inductance will have a very small affect on calibration. Roger

So a 50ohm metal film probably is going to be a horrible choice for calibrating my NanoVNA on HF at the end of a coax run not terminated with a coaxial connector (terminated with lugs to fasten to my

Carbon film resistors are made by depositing a thin carbon film on a substrate, and then a laser cuts a spiral into the film to achieve the desired resistance. That spiral cut will make the resistor

It will be a few days before I get home. Would you be kind enough to send me a good email address to which I can send a link. I’d rather not publish it here on the forum. My email is

Zack, You also need a good test jig when making these measurements. What are you using for your tests? Roger

Not hard to imagine that a nichrome wire wound power resistor will have a lot of series inductance. Metal film resistors are carbon ink coated ceramic forms. After firing they are trimmed to value

Hi. Same here !! Appears 27-30 mhz I have nanovna-f from deepelec. Is not problem of the firmware Humm. Nanosaver bug ...