Menu ⇓

Barnaby Walters

Arranging atoms and pressurising air in a variety of manners, such as:

Pronouns: they/he

  1. ↪ Aaron Parecki: I sold a washer/dryer on Facebook Marketplace, and now it's showing me new listings for washer/dryers. Glad to see the algorithm hard at work here.

    Apparently FB learned nothing from the classic “I bought a toilet seat on amazon and now amazon’s trying as hard as it can to fuel the toilet-seat-collecting hobby I’m apparently hooked on” problem

  2. A little-appreciated benefit of (British) English speakers learning a european language: you can look up recipes in that language and be guaranteed that they’ll use metric units

  3. This amazing comic from @Gingerhazing proves yet again that the best thing to come out of Star Wars is the lovingly crafted fan works which go places and tell stories the originals never would have dared.

    Parts 1-2 https://twitter.com/Gingerhazing/status/1489747577541070850
    Parts 3-8 https://twitter.com/Gingerhazing/status/1491149997676822530
    Epilogue https://twitter.com/Gingerhazing/status/1494087642081742849

    (Really hoping that they compile these into a nice readable format somewhere, it is just too good to be lost in the depths of twitter)

    Edit: there’s a full version up on substack!

  6. Annoyed by websites hijacking your favourite browser keyboard shortcuts? Here’s how to disable it in firefox (tested in ff 95, probably works in other versions).

    On a site-by-site basis: Go Tools → Page Info (cmd/ctrl + I also works, if it’s not hijacked), and block keyboard shortcuts:

    Or you can disable it browser-wide so that it never bothers you again, in about:config, by setting permissions.default.shortcuts to 2.

    In theory, 3 should prompt you on a site-by-site basis, but it doesn’t seem to work, sadly.

  9. I thought I was the only person who celebrated the spider of the year, but I heard that NASA just sent a big web into space?? Cool of them to get in the festive spirit like that

  11. Is there an institution or organisation somewhere whose explicit goal is to constantly run unit tests on basic physical phenomena, just in case, say, the gravitational constant suddenly changes or something?

  13. It appears that the popular Riden/Ruideng/RD Tech DP/DPS/DPH series power supplies use low-side current sensing, which can lead to some unexpected (and potentially destructive) behaviour in a situation where you have multiple unisolated power rails.

    For example, I put together a little box with a DP30V5A providing a variable, current-limited rail, and three LM2595 modules providing fixed 12v, 5v and 3.3v rails. As none of these supplies are isolated, and can therefore not be used to provide negative rails, I tied all their 0V outputs together. This led to the DP30V5A reporting a completely false current consumption of about 33% of the measured value.

    In the test setup, the DP30V5A is set to source 10V at a maximum of 5A. It’s connected (via a multimeter in 10A current measurement mode) to an electronic load set to consume 1A. Both the multimeter and load report a current consumption of 1A, but the DP30V5A reports only 0.29A.

    After sketching everything out, it became obvious that this was due to the low-side current sense resistor only seeing some of the current flow, and the rest flowing through the unused LM2596 modules (the switch A represents the internal connection between the DP30V5A 0V and the fixed rail 0V)

    Disconnecting the 0V rails and providing a separate 0V binding point for the fixed rails fixed this issue, and I’ll just have to keep in mind that if I want to use multiple rails from this mini PSU in the same circuit, I can’t trust the DP30V5A current reading and have to set its maximum current to about 33% of the desired value. Otherwise, the software overcurrent protection can’t function correctly, and there’s a risk of damaging both the module and the circut under test.

    An amusing side effect of this setup is that the DP30V5A low side current sensing can be used for the fixed rails! I doubt I’ll ever encounter a situation where this is useful though.

    More about high and low side current sensing in this AAC article

  15. ↪ Barnaby Walters: You’ve heard of biblically accurate angels, now get ready for bowl-accurate demons (cc @apocrypals)

    That first one was definitely the funniest, but the some of the other bowl-demons are pretty great too.

    A ceramic bowl with text around the rim, and a line drawing of two figures in the middle, one raising their arms up, the other upside-down and with a funny smile

    A ceramic bowl with text around the rim, and a line drawing of a figure in the middle with a large curved sword and a mischevious grin

    There’s a bit more detail about exactly what’s going on in this article.

    I’m surprised how timeless and appealing these little drawings are. They avoid a lot of the foibles which make a lot of late antique/medieval art look dated, and the exaggerated proportions, noodly limbs and googly eyes wouldn’t be out of place in a webcomic or cartoon.

    I also love that these bowls refer to themselves as “amulets”. Next time someone describes something as an “amulet” in a novel or TTRPG I’m definitely going to imagine it as an inverted bowl with a googly-eyed stick figure demon on.

  18. I’ve wanted to see an Alpine Rosalia (Rosalia alpina) ever since I first heard about them, and finally managed to spot two today! Very impressive beetles, lots of fun to watch them move, and they make a cute little scratching sound when disturbed.

    Photo of an Alpine Rosalia longhorn beetle at the base of a tree. Long, thick blue and black striped antennae, each as long as the beetle itself. A long rectangular body, blue with black markings