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Joined 1 year ago
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Cake day: March 31st, 2025

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  • now you have it straight from source:

    e/acc, distinct from EA, is a rival ideology about technology.

    (somewhere in this mix someone called me e/acc. i am not. if you’re going to classify me in this space, i am something like a Kurzweilian h+

    e/acc is a troll ideology for upsetting EA people and scamming pmarca.)

    then he complains about sneerclub for some reason, damn i can’t guess why

    if anyone has Rat Explainer For Normal People 101, not written by weirdos (derogatory) that would be useful i think now that what is known here for decade broke into mainstream

    LLMs doing Great Things Worth Ruining The World Over in medical research

    there are entire wet labs whose software stack predates openai. go and ask anyone who works in a moderately long operating lab if there’s any load bearing Thing that runs under windows xp control or older (there will be). there are some extremely limited applications of pre-llm ml in drug design, but it’s trained on entirely different type of data and it does entirely different thing and i’d say it’s not load bearing. these things are expected to be fed with new data from testing new things provided in previous iterations and if you hit something you’ll get there on your own. all of that data is noisy





  • openhamprep explanation is wrong

    When you consider a segment of wire, it has some inductance and capacitance in that small segment, and the wider it is, the lower inductance and higher capacitance are. In other words, both X_L and X_C go down as diameter increases. Electric field lines within antenna are mostly perpendicular to wire everywhere except on ends, where they spread in all directions, which means that there’s some residual capacitance there that needs to be charged each cycle. This is called end effect and the wider wire is, the more of it you get. In fact, the same aspect ratio (length/diameter) gets you the same end effect ratio each time, and it’s usually in range of 0.98-0.95. If there’s insulation, then insulation has lower velocity of propagation as it has higher permittivity than air, and it is in place with highest electric field intensity, and this can also shorten necessary wire length a couple %. The more insulation there is, the more shortened antenna becomes. have a calculator: https://www.translatorscafe.com/unit-converter/en-US/calculator/dipole-antenna/

    But wait, there’s more. We can think of antenna as a lossy RLC resonator (sort of), where R is Rrad which for halfwave dipole would be 72 ohms, + loss resistance which is smaller, and neither are changing fast with frequency. What is changing faster is X_L and X_C, and the wider wire is, the smaller both of them are (X_L = -X_C at resonance), and this means that you can go further off frequency and still have acceptable SWR, i.e. antenna made with wider wire has more bandwidth, or if we look at it as resonator, lower Q. For HF this means using masts or wire cages instead of single wire, but for VHF this gets more practical

    Resistive part of antenna impedance near resonance depends on physical antenna length, and if antenna is shortened, then how it was done, but for the range we’re here it won’t change much. But also it will depend on height above ground, type of soil, antenna geometry and many other things. 72 ohm is in freespace only

    you can consider antenna wire as a transmission line, but it will need to include ground as the other side of transmission line, and then impedance is dependent on wire diameter to height over ground ratio. it’s not very useful except when considering very large and currently uncommon types of antennas (beverage antenna and rhombic antenna, both of which are traveling wave antennas)









  • “there is a global far right conspiracy that attempts to reinvent alchemy, colonize space and build a machine god, which they intend to use to enslave everyone else. it’s informed by misreading of old scifi and racism, but it only took off after certain hp fanfic was written. currently it’s commanded by a californian polycule with a drug problem, but also counts in their ranks white house officials, and possibly some from russian government”

    unfortunately this does not make a great conversation starter. whaat? a cult took over an entire government of south korea? this could never happen here