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Joined 11 months ago
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Cake day: March 31st, 2025

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  • there was chrome (and firefox probably?) extension that went through your all fb liked pages and unsubscribed from them so that when it’s done timeline is gone entirely. fb went after its dev, removed that extension and banned him forever because it kept people off fb https://www.businessinsider.com/facebook-bans-unfollow-everything-developer-delete-news-feed-2021-10 doing this all manually still worked back then, not sure about today

    Facebook’s letter took him by surprise, he said, adding that Unfollow Everything had only 2,500 weekly active users and 10,000 downloads.

    “It was definitely growing, but it wasn’t huge,” he said.

    “Apart from that I just very much saw it as something that improves the Facebook experience for Facebook users,” he added, saying he got “amazing feedback” from people saying they “were using Facebook in a way that was much healthier for them.”

    slightly healthier relationship with attention devouring parasite in your pocket? not on zucc’s watch, ALL contents of your skull are to be sourced from and licensed to meta platforms inc exclusively






  • i was thinking more like, thin external plastic shell and empty cells inside, perhaps with another thin plastic shell on inside, and internal metal shell (on plastic support?) fitting in snugly, for mechanical stability, idk 3dprinting

    keeping leads short and nonmagnetic (dramatic reduction in skin layer depth) would be a good thing because of losses, but the longest object in capacitor would be just capacitor plates, and either way in wavelength terms it’s rather small. more precisely you can model it as open transmission line stub with some weird and low impedance, but it’s so small that you don’t have to. you can also make capacitor shorter and wider, or even add more layers like how vacuum variables are made. in nesting design you can get taper effect just by making inner layers longer



  • The dielectric between the plates in this case is 0.4mm of ABS plastics (+ a bit of air in the 3d print layer lines).

    in terms of losses, PP or PE is a bit better than ABS, teflon or FEP is a bit better than PP, but air is superior to either (this is part of the reason why foam coax is a thing). not sure which ones are printable, or whether it’s practical at this size, but try to introduce as many voids as possible (perhaps requires larger thickness of dielectric). it doesn’t matter much in your case, because of low power (warping of plastic because of excessive heat is probably not a problem). if your coax has solid dielectric, then by introducing enough air in 3d-print your variable might become less lossy than that

    The Capacitors allows my 80cm diameter loop to tune from 20Mhz to 37Mhz. Sweeping the whole range is a bit slow due to the low RPM of the motor and takes about 6min. But that is kinda nice when fine adjusting to a frequency.

    you have probably noticed that position vs resonant frequency relationship is rather nonlinear. you can get higher sweep speeds at lower end without losing much accuracy at higher end by tapering end of side plates into a triangle shape (it will get longer overall). it doesn’t matter much in your case, because it’s all approx monoband, but if you want to go multiband with this, then it’ll be a nice enhancement. similar effect happens when air variable capacitors have moving plates shaped in such a way that one end is longer than the other, and external edge has shape roughly like a section of logarithmic spiral. precise movement of variables like this is done by use of worm drive with large wheel

    I am not sure what is causing this, but i assume it could be due to increase of dielectric losses in the capacitor getting bigger when more of the plates overlap because then the electric field has to flow thru a bigger area of dielectric, increasing the potential for losses.

    loss tangent of dielectric is material property, that is ratio of equivalent loss resistance to capacitance should remain constant at given frequency. so i guess that losses should remain roughly the same, if dielectric is to blame, but at any rate lossy capacitor should make bandwidth broader and SWR lower. my guess would be that it’s a matter of coupling loop becoming wrong-sized or wrong-positioned at some point with change in frequency (try moving it up or down? there’s gotta be some optimum position for your entire range of interest)







  • i’ve collided with an article* https://harshanu.space/en/tech/ccc-vs-gcc/

    you might be wondering why it doesn’t highlight that it fails to compile linux kernel, or why it states that using pieces of gcc where vibecc fails is “fair”, or why it neglects to say that failing linker means it’s not useful in any way, or why just relying on “no errors” isn’t enough when it’s already known that vibecc will happily eat invalid c. it’s explained by:

    Disclaimer

    Part of this work was assisted by AI. The Python scripts used to generate benchmark results and graphs were written with AI assistance. The benchmark design, test execution, analysis and writing were done by a human with AI helping where needed.

    even with all this slant, by their own vibecoded benchmark, vibecc is still complete dogshit with sqlite compiled with it being slower up to 150000x times in some cases


  • yawn, i diagnose that LWer with weeb. this is something happening across entire industrialized world, causes being high performance mechanization of agriculture, old people being stubborn in regards to moving, lack of specialized work in countryside and couple of other factors. germany has patched their hospice staff shortage (not sure how effectively) with migrants, but japanese are way too racist for that. same thing happens in moldova, but you never hear sob stories about retired moldovans because they’re broke and nobody cares, while moldovan govt can’t really do much about it (because broke) to degree that it has not just economic and demographic, but even strategic effects. whole lotta drs strangelove in there