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Joined 1 year ago
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Cake day: February 1st, 2024

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  • That’s…not really a cogent argument.

    Satellites connect to ground using radio/microwave (or even laser), all of which are electromagnetic radiation and travel at the speed of light (in vacuum).

    Light in a fiber travels much more slowly than in vacuum — light in fiber travels at around 67% the speed of light in vacuum (depends on the fiber). In contrast, signals through cat7 twisted pair (Ethernet) can be north of 75%, and coaxial cable can be north of 80% (even higher for air dielectric). Note that these are all carrying electromagnetic waves, they’re just a) not in free space and b) generally not optical frequency, so we don’t call them light, but they are still governed by the same equations and limitations.

    If you want to get signals from point A to point B fastest (lowest latency), you don’t use fiber, you probably use microwaves: https://arstechnica.com/information-technology/2016/11/private-microwave-networks-financial-hft/

    Finally, the reason fiber is so good is complicated, but has to do with the fact that “physics bandwidth” tends to care about fractional bandwidth (“delta frequency divided by frequency”), whereas “information bandwidth” cares about absolute bandwidth (“delta frequency”), all else being equal (looking at you, SNR). Fiber uses optical frequencies, which can be hundreds of THz — so a tiny fractional bandwidth is a huge absolute bandwidth.








  • I just wish we’d have neither inflation nor deflation.

    Some tech has followed this pattern. For example: entry level Mac laptop in ~2000 was the iBook, priced at $1599 ($3k+ in today’s dollars). The current entry level Mac laptop (M4 Air) starts at $999 — cheaper in absolute dollars, and way cheaper in relative dollars.

    (Macs are just an example since Apple doesn’t have a very extensive product list, so there’s only one “entry level” laptop to choose from. And yes it’s fair to ask if the relative specs have just gotten worse, but I think this is also the opposite — the iBook was iirc criticized as being underpowered, whereas the M4 Air is afaik well regarded.)



  • You mentioned ham radio — definitely fun! It’s a process to get into it though, as you need to study/pass an exam, and then you need a radio. Radios range from cheap ($25 or so) in the VHF/UHF (“walkie talkie”-style) to more expensive for an HF rig ($1000 range for 100W HF). If you want to get into low power (“QRP”) it can be much cheaper. You also need a fair amount of space for a good antenna setup…

    There are tons of different communication modes, some without a computer and, like you mentioned, some that use computers. wsjtx and fldigi are popular programs.

    Good luck!






  • We’re expecting a baby. Do people travel with a baby? Is it safe? Is it insane? I think we’re just gonna have to stay put for 3 years or so.

    If your baby isn’t super fussy, the transportation difficulty (in our experience) is more in the logistics getting to/from airport, and dealing with other ground transportation. We just flew 5+hrs (coast to coast, US) with a 2mo and a ~3yo, and it was a piece of cake (typing that, I’ve jinxed the return flight…).

    We haven’t done international travel with our kids yet, but we will eventually. When I was 2 my family went to Europe — some countries were meh with respect to kids, but Italy (from my folks’ retelling) was fantastic, as there is (or was) a big cultural love for young kids.

    YMMV of course, but it’s absolutely doable! Kids — even starting as babies — have personalities, and you’ll get a sense of what’s appropriate with yours. Good luck!





  • Lemmy is not encrypted, my comments are public, your comments are public, we both know that. Anyone with a raspberry pi or an old netbook can scrape them.

    If I use an encrypted service and all of a sudden everything that I thought was encrypted was decrypted by the service provider without my consent? That’s breaking encryption.

    If on the other hand I use an encrypted service and they tell me that they can no longer offer the service, my data will be destroyed after X days, and I need to find another way of storing my encrypted data because of privacy invading government policies? That is not breaking encryption.