xkcd #3109: Dehumidifier

Title text:

It’s important for devices to have internet connectivity so the manufacturer can patch remote exploits.

Transcript:

[A store salesman, Hairy, is showing Cueball a dehumidifier, with a “SALE” label on it. Several other unidentified devices, possibly other dehumidifier models, are shown in the store as well.]

Salesman: This dehumidifier model features built-in WiFi for remote updates.
Cueball: Great! That will be really useful if they discover a new kind of water.

Source: https://xkcd.com/3109/

explainxkcd for #3109

  • AnyOldName3@lemmy.world
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    9 hours ago

    The cheapest hygrometers these days only have a digital output, and a wire and a potentiometer aren’t going to be able to query an i2c bus to ask the hygrometer what it’s measured without the help of a microcontroller (and the microcontroller might be cheaper than the potentiometer anyway depending on the specific model of each - have you actually looked at the 2025 prices of things before making assertions about what they cost?). The analogue component of a hygrometer that actually does the measurement gives fairly small changes to the resistance/capacitance (depending on the kind of hygrometer), so the results need amplifying. If you’re measuring on the same chip, you can get away with a simpler amplifier and digitally compensate for any nonlinearity, whereas to get a strong enough signal to make it to the rest of an analogue circuit without much degradation, you’d need an amplifier that ends up being more complicated than doing everything digitally.

    • Cocodapuf@lemmy.world
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      4 hours ago

      Look, I’ll be honest with you, I’ve never built a dehumidifier (I’m sure you’re shocked). I don’t know what exact components tend to be used. What I do know is that I have a fairly new dehumidifier and we have another one from probably the early 80s. Somehow they both work. Again, I’m not sure what components were used in the older model, but given the age I’d be very surprised if the electronics it uses would be more expensive to manufacture than the newer one.

      Really, I think the idea I’m trying to get across is just that you can always aim lower. Sometimes the goal isn’t achieving perfect precision, but rather achieving something good enough. Take toasters for example, most toasters don’t have a timer at all. They have a little piece of metal almost touching a contact. When you turn the toaster on, that metal heats up and it bends until it touches that contact, ding toast is done. And when you turn the little dial from light to dark it just moves that piece of metal slightly further from the contact. My point is, it’s not exact, it won’t be the same on every toaster, and it will probably shift over time. It’s a low tech solution for something that could absolutely be done in a more modern, more precise, and still inexpensive way (a simple timer). But it’s cheaper and simpler to just do it the old way, and for many applications, that’s fine.

      Hell, I’m certain there are dehumidifiers on the market that don’t have any kind of humidity sensor at all. Even simpler…