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Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

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Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#541
post #462

Earlier quoted context omitted.

If that's sarcasm, you aren't providing enough context for me to pick up what you are putting down. If not, then the honest answer is "I don't know for sure, I'm still researching it." From what I can tell, PM2.5 isn't the end-all be-all metric and sensors can give false readings. That's why I'm building multiple devices with different types of sensors and monitoring multiple metrics. PM10 and PM1.0 are also concerns…

Are you looking at BME680 vs CCS811 vs SGP30 or something else? https://www.jaredwolff.com/finding-the-best-tvoc-sensor-ccs8...

I am using the PMSA003 for the PMx sensor, the DS-CO2-20 for the CO2 sensor, and was about to order this sensor breakout for CO and other gasses though currently it looks out of stock: https://www.seeedstudio.com/Grove-Multichannel-Gas-Sensor-v2...

I might play around with the BME680 but it’s VOC detection is very rudimentary and it does eCO2 which is basically a guess. There is also the MICS-6814 breakout for relatively cheap on AliExpress but reviews on it are mixed, saying it uses the wrong values for its resistors and capacitors and it’s not as accurate as the Grove one. The Grove board is the only one that measures separate gasses separately instead of measuring total gasses and then using a formula to try to divide the number down to expected parts.

In practice, who knows. I need to lay my hands on all of them. If I could get all this into a controlled environment to test it all that would really be ideal.

Thanks for that link, it was a great read and the comments were helpful as well.

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#543
post #506

Earlier quoted context omitted.

strcpy() has entered the chat.

malloc, free and their little pointers snicker from behind a curtain.

I haven’t had as much trouble with those as they mostly do what it says on the tin. strcpy(), sprintf(), etc. all have slightly different semantics and even their “n” versions will do funky things if you don’t very carefully account for null termination. I find it way harder to use those because I have to keep remembering which of them does what regarding \0 at the end. And I guess now we have strlcpy() which is supposed to fix those issues but isn’t available on all platforms I use.

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#544
post #74
post #4

I still cannot get over this product. They whole selling point of a dyson fan is the 'air multiplier' tech, which creates a low pressure zone that propels air through the ring. According to dyson, this tech can move 15x more air than the fan in the base of the unit. Why in the world would you build an air filter around a system that does not directly interact with 93% of the air it moves? https://www.jameco.com/Jamec…

Fan intakes on non-purifying Dyson do get plugged with dust over time, so it makes sense to add filters. Aside from whether it makes sense to advertise them as air purifiers.

True, but that's only a secondary effect from the user's point of view.

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#545
post #511

Earlier quoted context omitted.

too many things have been lost or gimped. Chemistry sets, m-80s, model rockets, playgrounds, coaster brakes, whatever kids did before "play dates" and anything intricate with small parts.

There were probably too many things lost from "our" (n-1th generation) childhood too. Things like marveling at the first TVs, playing with unspent WW2 ammunition, etc. I'm sure each generation has its own things that they miss and think are detrimental to have lost, however I'm not sure that overall it's worse for the current generation. Hard to say. Growing up, I certainly would have loved having near infinite amoun…

>Growing up, I certainly would have loved having near infinite amounts of programming help available for free, instead of trying to decipher something from a 50-times photocopied manual.

Would you be as good of a programmer today if that was true? I remember spending an entire week trying to figure out how strings worked in QBASIC, when I was in 5th grade. There was no internet and I only had the Apple IIGS Basic manual to work with. I tried and tried and tried and eventually figured out that it had something to do with those $ symbols. Eventually I got the hang of it. I guess the point is, that challenge and struggle with simple things helped me develop the attitude to overcome truly difficult things later. Maybe this is more just memories of childhood than anything..

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#546

Earlier quoted context omitted.

The fan also sucks compared to something like a Vornado. "Buffeting" of air is not a practical issue when using a fan - you want a fan that can create a lot of air flow. The Dyson fan comes across form first then making up reasons to explain the form retroactively. It feels like an interesting look is the goal rather than something that's actually better. Am I wrong about this? Do people that have the fan like it? Is…

I had the dyson fan with the heater and filter for a short time, as well as a medify. I was disappointed with both, and returned them. The dyson looked cool, but the heat function was kinda useless unless you sat right next to it. i might get another one without the heat. The medify seemed to work well, but it felt like it was poorly made. I kept thinking I could probably diy something just as good. Though the main r…

I consider the heating as warm the air in winter before blowing it on me (while filtering) not warm the room

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#547
post #473

Earlier quoted context omitted.

The fan also sucks compared to something like a Vornado. "Buffeting" of air is not a practical issue when using a fan - you want a fan that can create a lot of air flow. The Dyson fan comes across form first then making up reasons to explain the form retroactively. It feels like an interesting look is the goal rather than something that's actually better. Am I wrong about this? Do people that have the fan like it? Is…

I bought one of the U.S. made Vornado models last year and couldn’t be happier. Great unit, fair price for a quality product.

It should be sold with ear plug. Loud so loud

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#548

Earlier quoted context omitted.

That makes me wonder if that was how the product originated. Dyson realizes its fans have a problem. Engineers suggest an air filter. Marketing see an opportunity.

The Dyson marketing person's angle is a sleight of hand: "Dyson has developed its own testing methodology, the POLAR test method, which, unlike the CADR, Hill said, "measures the intelligence of the purifier, the ability for it to know when that room is clean or dirty and automatically react, and its ability to mix that pure air around the room." The detection function seems of spurious value if the device is operati…

The latter. It works harder proportionally to the pollution detected

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#549
I'm in Australia and have a few air filters around the house. They're good when you live in semi-rural and have neighbours who like open fires, not to mention occasional bushfire.

A couple of different sized Philips which I like for the big colour led circle; two have PM2.5 count displays. But the air filters I have that really work are two Inovaair beasts. Solid all-metal construction and big drum filters that move a huge amount of air.

Had an oven mishap recently which filled the house with burnt oil smoke. One of the older Philips (a 6000 series) was soon showing well over 250ppm but was struggling to bring the numbers down. The big Inovaair had the whole downstairs clear and the Philips happily reporting single digits in about 20min.

Re: Dyson air purifier outperformed by cheap DIY box fan filter in Marketplace test

#550
post #423
post #422

Earlier quoted context omitted.

Haha I deserve the downvotes, it’s okay. I was being dumb because I thought it was funny.

It's a shame, I realised you were joking and I liked it. I think the idiomatic HN way to indicate this unambiguously but subtly is ending with "/s" for "sarcasm"

HN doesn't appreciate funny.
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