![James Nagel](/img/default-banner.jpg)
- Видео 84
- Просмотров 168 449
James Nagel
США
Добавлен 6 ноя 2013
PhD electrical engineer with a specialty in applied electromagnetics and numerical methods.
Видео
How to Measure Transmission Line Parameters with a NanoVNA
Просмотров 15 тыс.3 года назад
Measure characteristic capacitance, inductance, impedance, and phase velocity of a coaxial cable transmission line using nothing but a NanoVNA and some math.
Lecture 33---Step Discontinuities and Mode Matching
Просмотров 1,4 тыс.3 года назад
Lecture 33 Step Discontinuities and Mode Matching
Lecture 32---Multiconductor Transmission Lines (x3)
Просмотров 9463 года назад
Lecture 32 Multiconductor Transmission Lines (x3)
Lecture30---Quadrature Hybrid Coupler
Просмотров 4,7 тыс.3 года назад
Lecture30 Quadrature Hybrid Coupler
Lecture 29---Wilkinson Power Divider
Просмотров 10 тыс.3 года назад
Lecture 29 Wilkinson Power Divider
Lecture 28c---Directional Couplers
Просмотров 1,3 тыс.3 года назад
Apologies for the little mistakes. This derivation was weirdly tough to get straight for some reason.
Lecture 28a---Properties of Three Port Networks
Просмотров 1,4 тыс.3 года назад
Apologies for the gross sound quality. My mic wasn't registering, apparently.
Lecture 27---Binomial Matching Network
Просмотров 2 тыс.3 года назад
Lecture 27 Binomial Matching Network
Lecture26b---Multisection Transformer
Просмотров 1,9 тыс.3 года назад
Lecture26b Multisection Transformer
Lecture26a---Theory of Small Reflections
Просмотров 1,7 тыс.3 года назад
Lecture26a Theory of Small Reflections
Lecture 25d---Analytic Solutions for Series/Stub Matching
Просмотров 3443 года назад
Lecture 25d Analytic Solutions for Series/Stub Matching
Lecture25a---Series/Stub Matching Networks
Просмотров 1,7 тыс.3 года назад
Lecture25a Series/Stub Matching Networks
Lecture 24a---Lumped Element Matching (Intro)
Просмотров 1,2 тыс.3 года назад
Lecture 24a Lumped Element Matching (Intro)
Lecture22b---Impedance to ABCD Transformation
Просмотров 1,3 тыс.3 года назад
Lecture22b Impedance to ABCD Transformation
Lecture22a---Transmission (ABCD) Matrix
Просмотров 6 тыс.3 года назад
Lecture22a Transmission (ABCD) Matrix
Lecture21b---Scattering to Impedance Transformation
Просмотров 5833 года назад
Lecture21b Scattering to Impedance Transformation
Hello, you sure about ISOLN, what is the logic behind that? Because oficial tutorial says that "If there is only one load, connect the LOAD standard to port1( CH0 ) , the port2( CH1 ) can be left unconnected."
I doubt it matters much. The whole point is to just ensure that no signal from CH0 makes its way to CH1. If you can give a compelling use-case where the distinction makes a difference, I'd like to see it.
Can you please share what that book is ? it does not seem the book you mentioned by Clayton Paul
www.amazon.com/Analysis-Multiconductor-Transmission-Lines-Clayton/dp/0470131543
This is the best NanoVNA tutorial on RUclips. Thanks and bravo!
Thank you from Canada!🇨🇦
Wow, thanks to the RUclips algorithm and thank you very much for this amazing explanation.
Great work 👏👍👏 thank you
You're welcome!
life saver <3
Thanks for all the videos!
What book was that?
I cannot thank you enough. You explain so perfectly, that there is never a moment that i cannot follow. Everything makes sense
Should you be doing this with your coax coiled in a tight loop?
Hey mister James Nagel I wanted to thank you for your courses it helped me very much. Is there a Microwave engineering II course available ?
Thank you. This is very helpful.
Awesome! Just had a chance watching this 3 year old video. Could someone explain why Vp=0.67c?
@ 2:16 This substitution is done to get rid of the quantity dI and obtain a relation between V's only; the same for the I's, of course.
@ 8:49 What is so steady about the SSS?
@ 3:51 Unfortunately, this is NOT what's happening physically: because only negative charges (= free electrons) are moved by the potential difference. But the result is the same.
thanks!
thank you
Helpful ❤
Great video. Thank you!
Hello!
Great explanation! Thanks a lot
This is great and helpful
Very nice explanation, thak you sir. The Kernal in Fredholms equation is actually the Green's function if im not mistaken. This shows somehow the power of this method. If i know the Green's function i can apply this method to solve many different type of Problems.
Congratulations 👏
Greatly Imspired. Finding Helpful.
What is comformal mapping?
Page 85 Mapping by itself is a very elementary geometric technique.
Page 81 13. S. B. Cohn, "Problems in Strip Transmission Lines," IRE Trans. Microwave Theory Tech., Vol. MTT-2, pp. 52-55, July 1954.
Such a wonderful explanation, you're the best!
Thank you so much for making this video. Excellent explanation 😃.
What was the logic for performing the derivative of the equations with respect to Z? I know it generated the Helmholtz equation but I’m trying to conceptually understand why it was performed.
It is with respect to Z because in lecture 2b the transmission line was split up in little pieces (dZ).
Great explanation! Thank you so much!
In the simulation can you define the axis please ?? Thanks for the video series explaining wave modes from the beginning !!!
The best explanation I've seen how to understand why it is used 50 Ohm impedance cable. Thank you very much.
Hello Sir, For E(x,y,z) = E0*e^-j(ky*y + kz*z) in x axis, travel direction in z direction. Is it true that, if ky is not 0, then it is TE mode, if ky is 0, then it is TEM mode?
Can you get the transmission coefficient without using the matrix, such as voltage division?
Love you. Marry me please. You explain things so clearly 😩😭
very engaging coment
Tnx !
You are one great instructor!!!👌👏 I understand everything you teach!!!
Thank you
This video was helpful to tie the phasor math back to real signals in the time domain. Around 6:51 in the video you write ...- j*sin(...). Where did the negative sign on the j*sin term come from?
It came from his brain, but it is a small error. It should be +, like in Euler's formula.
Intersting to see that reflection cause current and voltage lag, so the source sees a reactive load, and VSWR is also well visualized
very good!!!!!
Thank you for this vedio this vedio was very helpful for me.From Egypt
So... in coaxial cable TEM is just "normal" electric circuit behavior and that's why it has no cutoff frequency? Despite coax's (or parallel plate's) gap size being centimeters it can pass 100 meter wavelength RF signals because the waves don't actually have to fit in the gap. They're from charges moving in conductors. And the TE/TM modes are very different mechanisms entirely where the space between the conductive cavities has to be big enough to support the electrical length of the frequency's TE or TM mode electromagnetic wave propagation? So tiny diameter coax in TEM mode can pass DC to some high GHz, it's actual size doesn't matter because it's just wires being wires (even if impedance is defined by the ratio of radii). But with a the TE_11 mode in a too big for the frequency coaxial cable, the absolute size *does* matter. And no centimeter size coaxial cable can pass a 100 meter size TE_11 mode wave (efficiently). But a giant 50 meter coaxial cable of the same impedance could.
in u another video u said V0 is a complex number..