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02 January 2021 Happy New Year all! If I do a OSL at the end of the coax to my horizontal top band loop and measure at the antenna end of the coax I see quite a lot higher frequency resonance than

Yes I have one side of the pair attached to center pin of CH00 and CH01. So center pin to center pin via one side of the pair, and the other side of the pair going to common on each side. Instead, I

The way the picture shows you have connected the CMC, you are not measuring CM rejection but rather DM which should be low. You need to tie both ends of the choke together and feed CM and sense CM.

I am such an idiot. Where you see type 61 in my text, please replace it with type 31. Sorry!!

Sirs, you have thrown down the gauntlet, Sir, and I accept your challenge. In my previous life, I was a more than adequate spreadsheet wiz. So I should be able to handle this job. haha. First, the

If you just want the characteristic impedance and not a plot of instantaneous impedance over time delay, there is a very simple relationship.? Average or characteristic impedance for a coax or any?

John, you gave good details on my scheme.? Perhaps I should have been more explicit but apparently I had it right, basically. Bob

Bob, I don't think you are remembering quite right. For the first method: Set the frequency range for Start 50kHz, Stop 500MHz. Calibrate (open, short, load) the VNA at the point where the unknown

Yeah works fine ! Mine was around 6€ Op za 18 apr. 2020 12:43 schreef hwalker <herbwalker2476@...>:

Use Smith chart display.? Sweep the frequency to find the place where the curve passes the first quarter of the circle, which is one eighth wave.? Move the marker to that spot and read the

How can I use a NanoVNA to measure the characteristic impedance of an unmarked length of coaxial cable? I have a NanoVNA-H4. I saw another thread here titled "characteristic impedance," but the

Yes. Thanks Fred KB4QZH

Well, I've sent this out twice yesterday, but I'll attach the tabulated data again. I probably need to take pictures and write this up to make it more useful to those who don't have all the test

Once again, he demonstrates that transformers do not make baluns as he measures only -3 to -4 dB of CMR of the typical current balun. And......the function of the balun is not necessarily to transform

Happy New Year Dave! Do you have a link to one your attachments or presentations that can guide those of us (who can¡¯t find the HP 8753C in the shack under all the other stuff!) using our nanovnas

As a wide hand wave, yes. Looking at my measured data for those CMC I measured both attenuation and resistance, there is a correlation between loss and resistance. However, it is not linear. Bottom

Download ZPLOTS from Dan, AC6LA. You run an S21, save the touchstone files. Then open the zplots spreadsheet, import the touchstone file and it will tell you all you want to know. --Shane

I too wanted to measure the resistance of my CMCs with my nano. And came to exactly the same point: LOGMAG via CH0 and CH1 giving me plots of -db vs freq. So to get resistance we need some extra math,

Kevin, I make Tx chokes out of Rg-400 as per K9YC cookbook. And for Rx antennas 75 ohm RG-179. http://k9yc.com/2018Cookbook.pdf I would post photos but no way to upload. Also have a look at these

I did some Velocity Factor (VF) measurements today on 9.4M of Belden RG-58A/U. The Belden specs give the VF as .66 or 66% of the speed of light in free space for this cable type. The first step was to