I am owned by several dogs and cats. I have been playing non-computer roleplaying games for almost five decades. I am interested in all kinds of gadgets, particularly multitools, knives, flashlights, and pens.

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Joined 1 year ago
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Cake day: July 2nd, 2023

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  • GPS was life-changing. (Yes, I am that old.) It used to be necessary to find printed maps of wherever you were going, which wasn’t always easy. Then you had to figure out a route. The hardest part was often the last bit of the trip, since you weren’t likely to have a detailed map of your destination city. An if you got lost, figuring out where you were was sometimes quite difficult.

    People tend to think of it as mostly affecting longer trips, but finding new addresses in a city was at least as much of an issue. When I lived in the bay area I had a Thomas guide that was 3/4" of an inch thick, just for finding my way around town.




  • To determine how long the signal took to arrive you would need to know the exact distance it traveled and its propagation speed.

    To calculate the shortest distance the signal could travel you would need to know the exact locations of the transmitter and the receiver. That, plus some trigonometry, would get you a minimum distance. That seems to be a good enough correction for things like GPS to work.

    If you really want to know the exact distance the signal traveled, it gets a lot trickier. Radio waves do not follow the curvature of the earth. To receive a signal that is beyond the range of sight, it needs to bounce off the ionosphere and back down to the surface. It may need to do that multiple times. That doesn’t always work, and when it does, it happens at various altitudes that vary based on a multiple factors. Without access to a lot more information, you will never know exactly how far the signal traveled.

    Then you need to know how fast the signal was moving over the course of its journey. Radio waves only move at the speed of light in a perfect vacuum. The chemical composition, and even the temperature, of the atmosphere affect how fast it moves. And, of course, those factors will not remain constant from the transmitter to the receiver. So you would need to know the exact route the signal took, as above, and then know the details of the atmosphere at each point over that route. That would require access to even more extremely detailed information. And a lot of computer power to make use of it.

    I don’t think there is currently any way you could get data about the signal bounce path. I am even more doubtful about getting detailed information about the composition and temperature of the atmosphere along the entire path.

    There are probably other considerations that a physicist would bring into this, but I’m just a layman.

    What is a sufficiently accurate estimate? That depends on what you need to do with it. There is no universal answer. The uncorrected time signal itself is good enough for nearly all purposes.

    Having said all that, I’m actually with you on this. It would make me happy to have the delay-corrected time, even though the difference could not possibly matter to me. I don’t need it. But it would be cool.


  • Just bear in mind that nothing involved in “refurbishing” a drive removes the wear it has already experienced. That may or may not matter to you. The mean time between failures for a particular model is a meaningful statistic, but it doesn’t tell you too much about any individual drive. You may get lucky or unlucky with the lifespan.

    If you check and monitor your drives, as various people have recommended here, you are less likely to be surprised by a failure. If you keep them backed up you won’t be out anything more than the replacement cost of the drive when it does happen.














  • I would be happy to see it replaced by something better, but I don’t want it to disappear. Having any kind of reference for source reliability, even just as a reminder to think about it, helps provide perspective on political posts.

    We live in an era where it has become normal to dump masses of bullshit online in the hope that sheer volume will convince people it’s true. Pointing out the credibility gap between NPR and Fox News is important.


  • Getting a university degree is essential for a lot of professions, but it should not be your only purpose in attending. It’s an opportunity expand yourself as a person while training for a job. Take some classes in non-technical areas that you know very little about. A few of them may lead to lifelong interests. Even if they don’t, they will give you a broader view of the world and the people in it.

    Even if you end up loving your job, there is more to life than work.

    I have a computer science degree and work as a developer and consultant. The most important things I learned in college were from some anthropology classes I took out of curiosity. Technical knowledge is not that hard to acquire. Gaining new perspectives on the world is a lot harder to come by. Take advantage of the opportunities.