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Video on planned obsolescence.
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james_s:

--- Quote from: tooki on April 10, 2021, 12:25:45 pm ---But it’s a big difference compared to the ~0.7 bar of the gas fill that we actually used in general illumination light bulbs, which is the point. Making a bulb that can temporarily withstand a vacuum during manufacturing is different from making one that can withstand a vacuum and household abuse at the same  time without breaking. Think about how fragile light bulbs already were, and then imagine if they were prestressed by a vacuum. No, they wouldn’t shatter if you touched them, but it certainly would reduce their maximum drop distance, for example.

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I have a lot of light bulbs, including examples of gas filled and vacuum filled lamps of various sizes. The glass envelope is not really any different between them to my eye. It's possible that there are differences but if so I don't think it's significant. Just surviving the bumps from normal handling probably requires more strength than a small vacuum filled bulb holding off the ambient pressure. Something else to consider, the pressure inside a gas filled bulb changes considerably depending on the temperature of the bulb. Putting a burned out bulb in a microwave oven makes a pretty spectacular show from the fill gas ionizing, but don't leave it in there very long or it will explode due to the pressure created inside the bulb by the hot gas.
David Hess:

--- Quote from: amyk on April 11, 2021, 05:39:17 am ---I suspect power surges may be killing them. There's a video about those you might like:
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That could be.  As I mentioned earlier, LED bulbs have an appallingly short operating life here.
SilverSolder:

--- Quote from: james_s on April 11, 2021, 07:18:41 am ---[...] Carburetors still have their uses, as do incandescent lamps, but they are no longer mainstream and it is not due to conspiracy but because other technologies offer compelling advantages in mainstream applications.

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That is a good point, and obviously not an example of conspiracy (or, in modern parlance, "antitrust").   I was more thinking, if the cartel hadn't blocked progress at the stage where they thought "good enough to make money, let's shut down competition now", what could the humble light bulb have become before the advent of the LED?
Zero999:

--- Quote from: JohnnyMalaria on April 10, 2021, 08:41:47 pm ---
--- Quote from: Zero999 on April 10, 2021, 04:52:56 pm ---
--- Quote from: David Hess on April 10, 2021, 04:31:19 pm ---
--- Quote from: Zero999 on April 10, 2021, 11:05:15 am ---There is no fan in my refrigerator. The evaporator is in the top of the enclosure and cools by convection. It's much more reliable than a fan. I have seen refrigerators with a fan, but I doubt they're more efficient, because the extra energy used to circulate the air, will probably outweigh the tiny saving in improved evaporator efficiency.
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Frost free freezers use forced air convection so require a motor for the evaporator.

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I don't have a problem with frost in my fanless refrigerator.

My freezer does frost up, but every couple of years, I take all the food out, cover it in bubble wrap and switch it off for an hour or so, with a bucket near the door. The ice quickly melts and can easily be removed using a butter knife. I don't see why anyone would bother with a frost free freezer. Doing this every year or two, is of little inconvenience.

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Ambient humidity plays a role. In spite of the complaints, it never gets that humid in the UK.

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I can see how it would be an issue for a freezer, but a refrigerator? The evaporator on my fridge doesn't stay below freezing for long enough to ice over. When the compressor turns off, it thaws, the water drains off through a sump, going to a small tray on top of the compressor, at the back, where it evaporates. If the fridge is icing up, then it will be because the thermostat is set too low.
madires:
No-frost fridges with fan have also a defrost heater in the evaporator unit plus a defrost sensor (NTC). And if you're lucky your no-frost fridge has a design fault causing the drain to clog up with ice (can be fixed with a piece of aluminum sheet).
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