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Where you can measure the input impedance of a cable pair, a good way to determine Zo is: Zo = SQRT(Zoc * Zsc) where Zoc is measured with the distant end open circuited and Zsc is measured with the

Hi guys, just happened upon this thread. Not sure if its applicable, but if you're measuring a scope probe it maybe more complex than you think (10x probe). See the attached patent on the scope probe.

We had discussed at length the measurement of characteristic impedance. See this production /g/nanovna-users/message/32568 Which shows how, with a nanoVNA, to calculate the

Zo = SQRT(L/C) is exact when R and G (primary constants) are zero. An exact expression when they cannot be ignored is: Zo = SQRT[(R + jWL) / (G + jWC)] = SQRT(L/C) * SQRT[(1 - j(R/WL)) / (1 - (G/WC)]

1) Be sure your coax is less than 1/4-wavelength long in the coax (considering Vp). Conversely, be sure your measurement frequency of measurement is less than the electrical length of the cable. 2)

Display, scale... Set to 0.2 (to multiply resolution by 5)... Dg9bfc sigi Am 07.11.2023 21:58 schrieb "Russell C. Nixon" <rcnixon@...>:

Can someone point me to a reference in the Wiki for screen scaling? I’m trying w1aew’s method for determining the characteristic impedance of an unknown piece of coax as an exercise. I’m getting

Tom, let me ping my friend in Woodland Park, Co., who retired from the scope division of HP about probe design. You've got my curiosity go'n. I'll report back. Dave - W?LEV

Hello Fran?ois, Yes, I've just tried an off-on power cycle with a fresh OSL calibration and all of the chart is now inside the perimeter circle.When I cycle the power on my nanoVNA it resets

I forgot that the group website inhibits direct downloading of EXE files, probably to protect the user against viruses. You can download check.exe here: http://ham-radio.com/k6sti/mu.htm Before

Use this Windows utility to check for reflection coefficient magnitudes > 1. It may provide insight when results are odd. http://ham-radio.com/k6sti/check.exe Brian

Gee, Dave . . . -632 ohms?? If you parallel it with a reaonator, does it oscillate?? ;-) I don't remember the 10430A exactly, and I'm too lazy to look it up, but typically the cable is rather high

Hello I use: - NanoVNA-F - nanovna-saver I often had this type of problem with traces on the Smtith coming out of the circle. I realized that if I RESET the nanaoVNA (directly on the box), before

Well spotted Mike! Cheers...Bob VK2ZRE

In the top left of the screen, it says "CH0 SMITH 0.5FS" - that means that the scale is set to half of full-scale, ie: it's zoomed in so that the outer ring of the smith chart is showing a magnitude

Not sure I follow you there Dave. I did an OSL before the measurement. How can any plot be beyond the perimeter given the right hand side perimeter represents infinity? Yes, the right hand side of the

Ah, but the VNA doesn't measure real and reactive impedance independently. It measures reflection coefficient, which, in this case has magnitude extremely close to 1.0. The VNA has only a finite

Not sure I follow you there Dave. I did an OSL before the measurement. How can any plot be beyond the perimeter given the right hand side perimeter represents infinity? Yes, but it isn't, it's outside

QUOTE: I attempted to generate a Smith chart using my NanoVNA and got the plots below. Port 0 is connected to an oscilloscope probe (x10) using a BNC adapter. Other end of the probe is connected to an

Hi, I attempted to generate a Smith chart using my NanoVNA and got the plots below. Port 0 is connected to an oscilloscope probe (x10) using a BNC adapter. Other end of the probe is connected to an