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Yes, you could do it with a 50 ohm analyzer and mathematically convert. I'm not sure a 75 ohm OSL kit would be super difficult. You'd have to choose a 75 ohm connector family (i.e. BNC, TNC, F, I

This is a long thread so this might have been mentioned already. I bet I am way out of line. Sorry. Why can't the measurement be made with a 50 ohm network analyzer? We're just looking at impedance so

This is the most recent video on my presentation: Nano VNA Part I The Basics (not much math) Nano VNA Part II The Under the Hood Approach (Advanced topics) I'll also include the latest PDF of the

I test ojisankoubou Z normalization code, adaptate it to NanoVNA Calibrate NanoVNA by 50 Om load Measure 25 Om (SWR = 2 and dot at left smith) After add DUT impedance as 25 Om and calculate how it

And quite a number of special applications use something entirely different than either 50 or 75-ohms, not to mention 30-Ohms. Take the 'flash' lasers at Los Alamos and Phillips lab, to name a couple

A resistive pad does NOT transform from a reference impedance of 75 ohms to a reference impedance of 50 ohms.? A transformer would (over some frequency range). All a resistive pad (of whatever loss)

Here is a good explanation https://youtu.be/I-OnQZJv35I wrote: Kenneth Hansen Owner

Actually, there is a good reason for 75 ohm coax. If you plot cable loss versus impedance, you will find that minimum loss occurs at 75 ohms. When you've got miles and miles of coax strung everywhere,

There are two issues: First the one from OP: he built at 50/75ohm pad and calibrated the NanoVNA with a 75ohm load. The pad transforms every impedance on its 75ohms side into the 50ohms world of the

I'd tend to agree with you that 50ohms is fine as a standard, who needs 75? However, as a reader of this thread I'd have to say that far from belly aching the active particpants in the thread are

All you need to do is make a measurement, reverse the DUT and make a 2nd measurement. What you proposed is fraught with trouble and would not work without a lot of effort. The DUT would see 25 ohms

All of the RF world standardizes on 50-Ohms as a system impedance (with very few special applications)................EXCEPT the television industries. Personally, I'm perfectly happy with a 50-ohm

last update for today: I found another spot in the calibration part that had 50ohm hard-coded. The diff attached to this post also corrects for that. for those who want to play along at home (with

Hi Larry, Thanks, I already saw your previous comment and finally checked out the wiki. Since I use the NanoVNAs almost exclusively together with a computer because of the larger screen a 75ohm

I quickly made a female 75ohm SOL cal set from 3 female SMA PCB edge connectors, the 75ohm load is two 0805 150ohm resistors in parallel which measures 75.36ohm with a multimeter. I then used my

ok that's ugly.. I attach the xls But t

Bear in mind that a resistive pad might provide "minimum loss" but is not an "impedance transformer" for making measurements. That is, it's not the same as changing the reference impedance on your

https://www.maximintegrated.com/en/design/technical-documents/tutorials/9/972.html Simple 75 to 50 and 50 to 75 Ohm minimum loss matching pads. These are lossy by nature, about 5.7dB. Best! Steve

Gentlemen - if you look in the forum's file section, you will find NanoVNA & H (not H4) firmware for 75 ohm by forum member Xenomorph.

It will not be perfect since as you pointed out the hardware (bridge, ...) is 50ohm but at least if you calibrate with a 75ohm reference all values displayed will be shown as referenced to 75ohm at