ComPhys @comphys@qoto.org

Small update to the TEM mode analysis with #FEniCS example.

I've added in a calculation for the mutual capacitance and self-inductance per unit length of the transmission line.

https://comphysblog.wordpress.com/2018/09/06/tem-mode-analysis-with-fenics/

#opensource #physics #python #ham

@QuantumHemp I don't personally use it, but I recently installed Ubuntu on somebody's laptop and was pretty impressed with gnome. The thing that I liked the most was how easy it was to customise the UI via little toggle switches on a website. Within a few minutes we'd installed a traditional start menu & taskbar and a weather indicator.

@freemo oh yeah =] nice, could actually convince me to use emojis.

The full code from the example, results etc are all on gitlab too https://gitlab.com/comphysblog/coax_tem the notebook has all of the steps and plots etc.

I've just finished my new post: TEM mode analysis with #FEniCS an #opensource finite element differential equation solver. https://comphysblog.wordpress.com/2018/09/06/tem-mode-analysis-with-fenics/

In this post I calculate the electric and magnetic fields on a coaxial cable, characteristic impedance of the line, the Poynting vector, the conductor and dielectric loss, an estimated loss coefficient, Q-factor and s-parameter for a given length of cable.

Coax has been a useful example for comparisons with analytical results but the methods are very general. TEM modes of systems with different geometries can also be analysed with the exact same techniques!

Very happy to hear any comments, corrections or suggestions.

#physics #ham #python

@Miredly@mastodon.technology @rey some of these concepts might be useful for you, for example in answering questions of whether gold coated cables are actually worth it etc.

@freemo I think it would be better if there was some kind of reference to mastodon generally as well as the unique personality of the instance? Perhaps a mastodon with a mortarboard, or a lightbulb over its head? Anybody that recognised the mastodon logo would be able to guess what the instance was about.

@mycroft@mastodon.social Not sure I'd personally self host a matrix or email server without good reason.
With email paying only a small amount every month gets me a service which is much more reliable than what I'd get with a raspberry pi on a home connection.
While I don't mind things being a bit unreliable for my own projects I can't expect others to deal with that when there are so many perfectly reliable options out there.

@HerraBRE all glory to the hypnotoad.

@HerraBRE not to mention the hypnotoad feature.

@mycroft@mastodon.social as in self-hosting?

@mycroft@mastodon.social that's cool :) matrix works really well in my experience; although it would be nice to see some more clients being made.

Starting my next post which will be about the TEM mode on a two-conductor transmission line. Specifically I'll be looking at a coaxial geometry and using #FEniCS to calculate the field distributions, the characteristic impedance and the Poynting vector. Just had a go and it all seems to be working.

While I'll focus on a coaxial geometry the method can be extended to more complicated geometries just by changing the mesh & boundaries. I've just had a go at an odd mode impedance and it came out just right!

The best thing about this post will be how easy it is.

#physics #electromagnetism #HAM #radio #Maxwell #opensource #python

@spinflip Hi, I don't have a direct answer to your question; I've never tried to do this before. However the problem makes me think of mosh ( https://mosh.org/ ) which is an ssh alternative specifically developed for intermittent connections and shoop which is an scp alternative. Perhaps these could be of use if the normal http method turns out to be difficult.

@jory Great stuff, thank you =]

\(\alpha\)

\(\LaTeX\)

Does the \LaTeX support work?

@hashtaggrammar @freemo @Surasanji @arteteco While this may be a good description of the problem, what's the solution? And is it even really a problem or will that tribalism just motivate both sides?