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Cake day: June 14th, 2023

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  • Chargers for RC model vehicles (car, airplane, helicopter) can do most if not all of that stuff, but you will have to be comfortable with soldering connectors as there is no universal standard connector system for any of the battery types you mentioned, and even standard size 18650/21700 cells are rarely used for RC purposes. The RC hobby has mainly settled on XT60 and its smaller cousin XT30 as the closest you’ll find to a standard, but even within the hobby many batteries use other connectors. Snipping leads and soldering connectors is not an optional skill, the currents involved can be very large and will easily melt a poor connection made with poor skills or some hacky clip-on connector.

    For charging, this is the sort of thing I use, no promises. RC chargers also include a balancing system to allow it to balance different cells across an entire battery pack but you will have to have individual wires junctioned in between each of those cells so it can sense their voltage and top them up as needed.

    Also most RC chargers don’t bother having anything to do with lead acid (automotive style 12V or otherwise), as they are much too high amperage and heavy for any sort of RC use and they use a wildly different charging design and have much more complex health monitoring and maintenance needs. Not recommended for that, use an automotive, marine or off-grid style battery maintainer and repairer for those. The one I linked says it does handle SLA (sealed lead acid) but I wouldn’t trust it to do a good job. Compromises have likely been made. You’d be better off with a dedicated unit for those if you are going to be dealing with them.


  • That’s false. You can literally not only feel heat from, but you can in fact set things on fire with, a completely monochromatic green laser with a wavelength exactly in the middle of the visible spectrum. No infrared, no ultraviolet. Lots of heat transfer. You could do it with an ultraviolet laser too if you were careful enough and could get around ultraviolet’s tendency to destroy molecular bonds completely before they even have a chance to burn chemically. It’s not just lasers either, any light source is going to deposit energy in the form of heat on anything that light touches. Any light contains a large amount of energy and some of it will get absorbed by anything it interacts with, and that’s still true whether it’s infrared, ultraviolet, somewhere in between, or all the above.

    Infrared has a special relationship with heat, yes, because of the distribution of blackbody radiation, but “No” is absolutely the wrong answer here. The right answer is “Yes, but… it’s complicated”.



  • Oh absolutely. Smart TVs are completely under the control of the technology and media companies with very little hope for freeing them, except that you can still plug a computer into them to bypass all the “smart” features and just use it as a dumb screen with a smart computer instead. But they always seem to put a few new stumbling blocks in the way of both those options every year. That loophole will eventually get closed, it won’t happen overnight, but they will keep eroding the functionalities and convenience of doing so until few if anyone wants to do that anymore.

    Cars are nearly a lost cause too, except where regulations say they must use some standard like OBD2 for “emissions reasons”, although that is obviously a limited scope and manufacturers try to find any ways they can to sabotage it or otherwise avoid it. Appliances and “smart homes”, all the way down to the light bulbs and LEDs, have plenty of proprietary, locked down, unrepairable technology in them too despite reliable open standards being available. The war for total control over our digital devices is in full swing and there’s no area of our lives from large to small that isn’t a battleground. People need to keep prioritizing the freedom of their devices because once they get these technologies and features entrenched it’s going to be very hard to work around them.


  • I mean, they did it with phones too. Android is just Linux. That was one of the main attractions, for me at least.

    At first, many people and groups supplied their own phone OSes. There was a whole thriving community ecosystem. Then they started to make it really hard, locking bootloaders and including critical pieces of hardware that didn’t or couldn’t have open source drivers (look up WinModems for a very early example of this technique, it remains really effective) or otherwise required extremely convoluted methods to access and the phone might function marginally without some of these fully functional, but at least you could still install a custom ROM on it if you were stubborn enough.

    But even that wouldn’t last. Nowadays they’ve made it literally impossible to defeat the security on most phones, in the name of keeping hackers and criminals out, but really a big part of their motivation is blocking these pirate OSes that let you actually control the hardware and software in your phone, doing criminally nefarious things like stopping them from downloading ads (the horror!) and preventing them from funneling all your data and activities back to Big Brother (how rude!) and worst of all updating it with modern functionality after they’ve declared it “obsolete”. The goal going forward is to sell you things that you don’t and can’t control, so they can shut them down or make them gradually more and more useless and make you buy new ones forever. They want you to have a subscription for everything including physical objects without realizing that you’ve been forced to subscribe to their regularly-scheduled-disposable-device-replacement-plan for no actual reason.

    They’re coming for computers too, or at least they’ll try. They want control of everything we interact with. For profit, mostly, but I wouldn’t rule out other motives. It’s a powerful thing when you have control of everything people see and do.




  • Most cheap non-dimmable LEDs have drivers that use resistors to determine the current to drive through the LEDs. As a rule, these are always set too high to overdrive the LEDs (sometimes as much as twice their rated current) for marginal brightness gains and to burn out the bulb prematurely. I’m obviously unable to actually see directly into the operation of the great minds that design LED lightbulbs but logic leaves me with only those two plausible conclusions, I’ll let you decide which motivation you think is a bigger factor for most manufacturers.

    Conveniently, most manufacturers carefully fine-tune this value to prematurely destroy the LEDs at just the right time, which requires careful balancing of resistors, and even MORE conveniently (for us) the cheapest way for them to do this is typically to use two resistors. And MOST conveniently (for us), if you were to carelessly break one of the pair of resistors they use, and leave the other one intact, the current would immediately drop to a very reasonable and appropriate level, generating much less heat, drawing much less power, making LED death extremely unlikely, and only modestly reducing brightness in many cases, because LEDs have non-linear brightness and the heavily overdriven ones are typically FAR beyond the point of diminishing returns. In some cases the reduction in power results in basically no visible difference in light output. In some cases it can be argued they’re literally stealing extra power from your electricity bill and using it as an electric heater for no purpose other than to burn out your own light bulbs prematurely so you have to replace them.

    The good news is, like I said, removing one of the responsible resistors instantly solves the design flaw and is usually quite easy even without any special tools or electronics knowledge. BigCliveDotCom calls this “Doobying” the bulbs after the Dubai bulbs that were mentioned in other comments. If you watch some of his videos about LED bulbs you should be able to see the pattern of which resistors to remove, if they are on the board they will basically always be right next to each other and relatively small values (typically in the 20 ohms to 200 ohms range). The only modification I make to his procedure is that I prefer to remove the HIGHER value of the two resistors instead of the lower one, which results in perhaps somewhat less lifetime preservation (still much more than the original setting) and less power savings, but more brightness, and is usually adequately good for my purposes. I also use sturdy tweezers to remove the resistor instead of a screwdriver which seems to me that it would have a higher risk of collateral damage.

    Is it a lot of work for a single light bulb? Kind of, yes. But once you get it done a bunch of times, you’ll probably rarely have to do it again, as these bulbs last almost forever. In fact, I have yet to have one actually fail, I am mostly just replacing the occasional old unmodified LED bulb from time to time.

    This will not work with dimmable bulbs or certain fancy high end bulbs. Also some are much, much easier to modify than others. Clive calls the ones that are relatively easy “hackable” and it’s really a crapshoot to find them. Some have covers/bulbs/diffusers that are nearly impossible to remove without catastrophic damage to the bulb and/or your hands. Others simply use a different circuit design that doesn’t have resistors. Some only have a single resistor, meaning to change the value you need to solder a new one in its place. In my experience, the bargain-basement, junkiest, least reliable bulbs tend to be the easiest to hack this way and often skimp on things like “gluing the lens on” so it’s easy to get off. But you’ll have to experiment to find a brand and style that works well for this.





  • Keep the gray plastic. Remove black clip around the vertical wheel post in the gray plastic. Remove wheel and wheel post. Buy new wheel. Installl new wheel. It will be easier to find a new wheel once you have the old wheel out so you can take measurements. but it’s likely something pretty standard, off-the-shelf. Wheels are something that companies buy, they rarely build them themselves. They typically come as a castoring assembly with wheel, axle, spindle, and attachment post in a variety of common sizes and with a dizzying variety of actual wheels.


  • a) Forecasts are very resource-intensive, they are performed on a specific schedule using a computational forecast model. Updating the predictions would require inputting new data and running the model again, and by the time they do that, the next forecast will already be out.

    b) Do they know it’s wrong? Where did you get the temperature? From an official weather station? If not, there is no reason to imagine that someone is noticing that this one particular model run was wrong in one particular spot across the whole country and trying to fix it in real time.

    c) If you did get the current temperature from an official weather station, that IS your update for it. Real time data from official weather stations is always going to trump the forecast model. What would be the point of updating the forecast when the current measured data from the weather station is now available? That’s like driving down the highway and saying “I was predicting my speed would be close to 65mph, but due to the heavy traffic I’m seeing today, I’m going to re-estimate my speed to be 45mph” when you have a perfectly accurate speedometer right in front of you telling you exactly what speed you are going at all times. Forecasts are only useful for the future, and they can be wrong.


  • It is. The web was eventually corporatized and the corporations sucked all the air out of the room suffocating anything too small to compete. The fediverse is, if not taking it back, at least opening a space for those who don’t want to consume from a fully corporatized web. These include many of the people who used to make “websites” instead of “apps” or “platforms”. When people complain that it doesn’t have as much content as say, Reddit, I look at that as a benefit, it’s helping solve the (massive) discovery problem by self-curating thoughtful people who can curate content intelligently and provide real opinions and meaningful thoughts. The signal to noise ratio is much higher, and it’s refreshing.


  • They’re only lying as long as people can continue to over and over find their way around the obstacles they place in the way, and it gets harder all the time. They have more money and more resources and more organization than the hackers trying to defeat them, they’re winning the war of attrition. We may be able to make small breakthroughs here and there, but overall we continue to lose more and more territory, because the amount of effort is disproportionate to the goals. Most of what’s left of the custom ROM community has given up on the losing battle with manufacturers and providers and changed focus to the various freephones but even they have their own troubles and are fragmented and short-lived. Between carriers, manufacturers, and content providers the whole mobile ecosystem is designed to be impenetrable. It is intentionally a fortress full of deadly traps and open source supporters have no hope to breach it anytime soon.



  • It’s possible but not likely or common. Glass is stronger than most people give it credit for. Most “hollywood” glass is actually panes of sugar. You could certainly arrange things so that the gun’s pressure wave has a good chance of stressing and breaking glass, but it would take special preparations and effort and the gun would probably have to be very close to the glass. It’s almost unheard of for it to happen normally unless you specifically shoot at the glass.

    Someone like mythbusters could probably test this pretty effectively, but based on my experience around guns and glass, I suspect they’d come to the same conclusion.

    A not directly related but still interesting video was done by the slowmo guys on youtube


  • It’s veeeeery not standard in Canada. I use it on my phone and most people who see it on the lockscreen treat me like I’m an alien, and it’s about a 50/50 mix of people who simply think 24 hour time is weird (but at least recognize it) vs. people who seem genuinely baffled by the digits they see appearing on my phone and don’t even seem to recognize it as a time at all.


  • No good reason, just historical inertia and resistance to change. People stick to what they’re familiar with, either the imperial system or to common metric units. Making a “metric ton” similar in size to an “imperial ton” arguably helped make it easier for some people to transition to metric.

    Megagram is a perfectly cromulent unit, just like “cromulent” is a perfectly cromulent word, but people still don’t use it very often. That’s just how language works. People use the words they prefer, and those words become common. Maybe if you start describing things in megagrams other people will also start doing it and it will become a common part of the language. Language is organic like that, there isn’t anyone making decisions on its behalf, although some people and organizations try.