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$1400 a year in electricity at a high rate of $0.15/kWhr for all 8,760 hours in a year is about 1 kW in power savings. Reality check:

A typical 3-phase 2hp industrial motor [1] is over 85% efficient and typical 10:1 reduction gearbox [2] is 94% efficient, which results in about 3kW power usage and 20% power lost to heat, or approx 0.6 kW. If their motor is 100% efficient, used in a 100%-duty-cycle application, in an area with high electrical costs, and with similar reliability to the standard AC motor, this gives $800 or so in savings per year.

In a more typical application with a 50% operating duty cycle and $0.10/kWhr, and guessing at 96% efficiency for their motor, we're down to maybe $200 per year in savings. Larger (>=5hp) motors can be 91% or higher efficiency bringing savings down even more. I can't imagine how C-Motive will equal the reliability, so any extra maintenance could quickly wipe out the savings.

I would guess that a variable-frequency drive (VFD) on the above AC motor, used to control speed and improve the power factor, would have the same efficiency as their motor controller. So I only looked at the AC motor + gearbox versus the C-motive motor + fluid pump.

[1] - https://www.baldor.com/catalog/CEM3558T-5#tab=%22performance... [2] - https://www.bostongear.com/ecatalog?page=product&cid=worm_ge...


I often ponder what the generator algorithm might be when I am solving "insane" 13x17 Kakuro puzzles [1], because there always seems to be just enough logical paths to solve each puzzle. Well done!

[1] - https://krazydad.com/kakuro/index.php?sv=13x17I_v1


All the underlying claims by the author really need the sources referenced.


I would suggest the same hardware solution, where the USB powers a device-side presentation of the raw data into a more universal mass storage device. This also allows file transfer to any device without requiring special software. I did something like this in 2008 or so (using a FTDI chip and PIC mcu, and boy was it ever slow).


As usual it's complicated, and it depends on which study you pick, and which model and parameters the researchers used. This study suggests that more anthropogenic sulfate aerosols in the air (usually from burning coal and other fossil fuels) could cool Artic summers from low clouds but warm Artic winters due to high clouds:

https://www.frontiersin.org/articles/10.3389/fenvs.2021.7665...


Absolutely essential. Fumes from lead-free solder fluxes are nasty [1]. I find that bench-top "fume extractors", consisting of a fan and thin dust filter, are extremely noisy and essentially useless. I love my Hakko FA430-16. It's relatively quiet such that a regular conversation can be had in its presence, and it really works with the right hose & hood setup.

1: https://www.hse.gov.uk/lung-disease/electronics-soldering.ht...


I wouldn't call the simple fans useless - just the fact that the fumes are being blown away from your face is a huge improvement over not even having that.

Of course there needs to be somewhere for them to go, but if you can have an open window close to your bench, that solves that problem quite nicely.


As someone who owns a FA430 and has a sensitivity to flux fumes causing headaches and drowsiness, I agree with everything in this comment. Keep in mind you can become sensitized to flux fumes after repeated exposure (happened to me) so IMO it's better to go overkill on fume extraction before it becomes a problem.


> I find that bench-top "fume extractors", consisting of a fan and thin dust filter, are extremely noisy and essentially useless.

Compared to no fan/filter, they're A LOT better, I'd say. And a relatively small price to pay for such an improvement.

But yeah, they're not nearly as good as a real fume extractor.


The F-22 service ceiling is 60,000 ft so it can get up there too. The U2, however, flies relatively slow (< 400 kn) at that altitude so is ideal for an up-close inspection.

I would think that the U2 internal cameras were designed for a long focal length and for objects below the aircraft. I wonder if they made modifications for balloon photos.


The U2 contains a far more advanced sensor suite than just cameras. With something like this balloon I suspect the signals intelligence is at least as interesting as any visual reconnaissance.


And here's Dick Proenneke's way of doing it, pre-Internet:

https://www.youtube.com/watch?v=iYJKd0rkKss

[edit: originally stated he was an Army engineer, but turns out he had various hands-on jobs, one being a Navy carpenter during the second World War.

https://en.wikipedia.org/wiki/Richard_Proenneke]


I much prefer Dick Proenneke's dream of living in the wilderness.

And I'm sure Dick Proenneke, if he were doing it today, would have a bank of solar panels and satellite Internet.


In a similar vein, I quite dislike Microsoft's personification of Windows in the messages such as "We couldn't log in ...", "Let's finish setting up ..." or "We are adding new features ..."


To me it shows Microsoft's attitude that Windows is a little tunnel into your house through which they can act.

The computer isn't doing a thing. The user isn't doing a thing. The vendor is doing the thing, using the equipment they've got in your home.


Hmm. An engineered tree introduced to the ecosystem. What could possibly go wrong?


VC funded no less.


So even if it ‘works’ we’re fucked because they have a monopoly on creating our air supply.


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