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The light works. The gravity works. Anything else we have to take our chances with.

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``Lost forgotten technologies,'' Donovan said. He sighed and tossed the cassettes to his bed. ``Our remote ancestors poked reeds into mud and baked mud into brick. We can still read those ancient thoughts, millennia later. But it seems that the greater the technology, the more ephemeral it becomes.''

This is the kind of alien bunny you can get from an ordinary half-wave dipole with the wrong mesh.
The difficulty is to understand which mesh is correct:) I honestly followed all the recommendations (cell size, no nodes exactly on the metal-air boundary, location of the feeding port), but it's not enough. I will keep trying.

``warning: findstr is obsolete; use strfind instead''

Does someone have it in their ass, or do they have nothing better to do than change the words in the function names?

YRabbit boosted

Hmm... the hairdresser called and canceled the haircut due to illness. Well, I'm going into town anyway: I need to get some boards:)

For practical purposes, we can assume that one antenna is precisely positioned relative to the reflector (not even a day of calculations🙂 ), now the funniest thing: check that the other antenna is also in the acceptable range of Zreal and Zimg🤣

``should allow the Raspberry Pi Foundation to unlock this functionality for free'' 🤣

For the third year in a row I have inquired about the free codec from RPi and each time there is some lost tribe on the shores of the Amazon where the patent is still valid.😜

I can add reflective edges, but it will make it difficult to clean the antenna, which can be solved by building a fully enclosed case, as a result of which the antenna will lose its charm🤣

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There is still a lot to calculate. Each simulation takes an hour and a half with six threads on Ryzen3 3100. Increasing the number of threads will only worsen the situation: if you are familiar with the methods of numerical simulation, you know that the processor processes a huge array of data from memory sequentially, and the bottleneck here will be the speed of exchange with RAM, speed and multi-core are secondary here.
In theory I can replace my memory 2666 to 3200, but it's too much:)

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In principle, I am happy with the picture that is emerging. I knew that I had to compromise on the parameters for appearance reasons: I cannot spread the antennas too far apart, I cannot make a reflector of the recommended width because I will make a half-meter monster, which does not look like a room antenna at all, and the modem will not withstand the conditions outside.

This time I'm purposely making the shape of the antenna ``broken'' in order to get several S11 peaks and thus expand the effective bandwidth.

Gee! I learned how to combine two different scales on one chart!

This is what you can get after a few hours of simulation if you did not write the command quite correctly🤪
Well, I can still say that the peak efficiency is probably at the frequency I need, 1800MHz😉
The slowdown happens when the swap is engaged, it's raining outside, but maybe I'll go for some DIMMs after all.

Well, all the geometry is parameterized, I can turn off the visualization and start experimenting:)
Although the insulation of the antennas is too good, I probably made a mistake somewhere.

``The transformations are applied in the order as given inside the {} brackets.''
It didn't immediately dawn on me that this isn't a list at all, but rather the order in which the unique slots of operations are applied: I can't do { 'Rotate_X', pi/3, 'Transform', [2, 3, 0], 'Rotate_X', pi/10 } --- only the last Rotate_X will work.
Thank goodness there is another rotation slot 'Rotate_Origin', and 'Matrix' as the last resort.

The command line auto-complete the filenames!
🙂 I just didn't notice that it wasn't a shell. Unexpectedly.

YRabbit boosted

This DuckDuckGo audit by @purism is a sobering read:

Remember that DuckDuckGo is venture capital-funded which means that they must exit—either become a publicly-traded multi-billion-dollar company (sell to the public) or sell to one of the incumbents.

(What we need is a publicly-funded but independently run search engine. The EU could create such a thing… if they didn’t have they heads firmly entrenched up Silicon Valley’s bumhole.)

HT @koherecoWatchdog

Time to listen to a couple of lectures on : I could describe one radiator without going into it too much, but experiments with the mutual arrangement of two require a parametric description of their geometry.

You will no longer find the x11-wm/goomwwm port --- I use it at this second as I have for decades, ports-mgmt/portmaster is a very useful thing for me --- it is no longer in the ports etc

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I couldn't resist bringing up the science/paraview port from the dead: it's more convenient to view the results right there without copying them to a remote machine.
It wasn't difficult. This is not the first time programs have disappeared from the repositories, not because they are not working at all, but because... I don't even know why, maybe to encourage migration to new and shiny things.

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Mastodon @ SDF

"I appreciate SDF but it's a general-purpose server and the name doesn't make it obvious that it's about art." - Eugen Rochko