Post B2HeAXjFz8SdyDG3I8 by argv_minus_one@mastodon.sdf.org
 (DIR) More posts by argv_minus_one@mastodon.sdf.org
 (DIR) Post #B2HeATeV8sHRKJ0CK8 by argv_minus_one@mastodon.sdf.org
       2026-01-14T17:54:43Z
       
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       Saw some people complaining that mercury switches were banned and replaced with newer switch designs that are less reliable and therefore make more money for the manufacturer.…I'm sorry, what??? We replaced mercury switches with transistors, and some of the transistors in service today are older than I am!Also, mercury switches aren't banned. You can buy them on Amazon right now. They just aren't popular any more because, y'know, toxic and mostly obsolete.#electronics
       
 (DIR) Post #B2HeAUTu3lOftj3FRY by publius@mastodon.sdf.org
       2026-01-14T18:17:02Z
       
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       @argv_minus_one I mean, household light switches based on mercury may well have been banned. That one is a trade-off. On the one hand, they are arc-free and therefore will probably never cause a fire. On the other, if a fire occurs anyway, mercury gets everywhere ; and there is the problem of final disposal to consider. Can you be certain that the switch will be pulled out intact for re-use, and not landfilled, or crushed during demolition?
       
 (DIR) Post #B2HeAXjFz8SdyDG3I8 by argv_minus_one@mastodon.sdf.org
       2026-01-14T18:06:58Z
       
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       Only mostly obsolete, though! If you really do need to switch based on the device's orientation relative to gravity, then a mercury switch is still one of the ways to get the job done.There are other options, like accelerometers and solid-metal-ball switches, but these tend to have some other trade-off. Accelerometers are expensive and require a computer, for instance. But they won't give you any horrible diseases if they get broken, so there's that.
       
 (DIR) Post #B2Hf8ovBC3SSfMZqCW by argv_minus_one@mastodon.sdf.org
       2026-01-14T18:28:16Z
       
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       @publius I wasn't under the impression that our modern light switches were starting many fires either.Not-fun thing about that: I just read that a light switch might be dangerously failing if there's a delay before the light comes on…but some LED lightbulbs have a delay even when everything is working normally!
       
 (DIR) Post #B2Hg7YnFlqoEJLpghM by publius@mastodon.sdf.org
       2026-01-14T18:39:10Z
       
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       @argv_minus_one I have occasionally noticed an arc "pop" when I flick a light switch, sometimes with a spark visible through the switch body if the room is quite dark. This may not translate to much of a real-world risk of ignition unless the atmosphere contains flammable gasses (in which case you typically have bigger problems), but I could certainly understand if it caused someone concern. It doesn't exactly make me feel good.