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flaviu2on New Model M Is an American-Made Keyboard That Puts a Spring Back in Your Typing

It does, a bit. If I wanted to make a rubber some keyboard, I'd have startup costs in the thousands of dollars range for molds and such. But I can make PCBs for a mechanical keyboard for only $30.

The cost of mechanical keyboard is far lower in low quantities.

flaviu2on Show HN: AnyLeaf – PH Sensor for Microcontrollers

That's a capacitive moisture sensor. It is incapable of measuring pH.

flaviu2on Simultaneous AP and Client Mode Wi-Fi on Raspberry Pi Zero W

I'd guess the hardware is the problem. Most antennas I've seen on access points are larger than the entire Pi Zero W. While I'm no radio expert, I'd expect APs to use the smaller antennas if they were capable of being as good as bigger antennas.

flaviu2on Compressed Sensing (2016)

> Compressed sensing in this context is made possible by the fact that the signal’s frequency content is highly sparse.

The fact that the signal is so regular is what makes this possible. You're sampling the same signal many times, far more than twice the frequency of the highest frequency.

If the signal's frequencies changed over time or if there were more frequencies in the signal, this wouldn't work or would require far more data.

flaviu2on Health Concerns Mount as More Old Sewer Pipes Are Lined with Plastic

ah, I see.

> Emissions from a nearby CIPP job got indoors through cracks in the building’s foundation and irritated workers to the point that they evacuated

This is fascinating. I've always thought of dirt and concrete as being basically impenetrable to things like this, but apparently they're not!

flaviu2on Health Concerns Mount as More Old Sewer Pipes Are Lined with Plastic

I'm familiar with vents, but indoor vents are basically one-way air valves. I don't know if this is required by code, but it's definitely common practice (you don't want poop smell coming out of your vents)

flaviu2on Health Concerns Mount as More Old Sewer Pipes Are Lined with Plastic

I haven't read 100% of the article, but from skimming over it, I see no mention of p-traps [1]. How exactly are these fumes getting into places when there's essentially an airlock in every drain connection?

[1]: https://en.wikipedia.org/wiki/Trap_(plumbing)

flaviu2on Cue – A language for defining, generating, and validating data

Seems like an interesting language, but I'm very disappointed that my first attempt to view example code took 5 clicks.

The most important part of any programming language website is a short example snippet: put it above the fold on the front page!

flaviu2on Ceramic-bearing bicycle drive shaft (2018)

https://www.ceramicspeed.com/media/3505/velonews-friction-fa...

See page 63 for efficiency and 64 for longevity.

The graph on page 64 is confusingly labeled, but the numbers indicate "watts expended before wet dirty run" - "watts expended after".

flaviu2on Universal SSL

Sure, but that is only helpful if you remember that the site had previously worked before. Otherwise, it's just like your first time visiting it.