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Comment: Re:3L per square meter per hour @ 75 percent humid (Score 3, Informative) 173

by Formalin (#42072171) Attached to: Water Bottle Fills Itself From the Air

Your math is off. I don't have a 710ml bottle handy, so I did a 12oz can.

Assuming 6.5cm * 12cm, ignoring the bottom and top surfaces, just the sides of the cylinder, I get 490 cm2, which is .049 m2.

3l * .049 = 0.147; 147ml/h. The can will be a 40% full in an hour, in 75% RH.

I assume the performance in drier conditions is much worse, though.

Although, once the liquid is in the container, it loses surface area? I didnt bother reading to find out whether the inside or outside or both count. math was assuming one side.. If it is the inside surface that does the work, the increasingly covered surface will give reduced efficiency as it approaches full...

Comment: Re:Shocking. (Score 1) 363

by Formalin (#42061851) Attached to: High-Voltage Fences For Zapping Would-Be Copper Thieves

Not sure what you're on about. Maybe you should look it up in oxford first.

Definition of electrocute
        injure or kill someone by electric shock: a man was electrocuted when he switched on the Christmas tree lights
        execute (a convicted criminal) by means of the electric chair.


late 19th century: from electro-, on the pattern of execute

Comment: Re:OMFG Reagan was right? (Score 1) 861

by Formalin (#42039753) Attached to: Israel's Iron Dome Missile Defense Shield Actually Works

Something tells me the Palestinians aren't using bleeding edge Russian or US ICBMs.
If the system was effective against that, you might have a point, however I doubt it would be.

I think there's only one way things end up if MAD is disturbed too much, maybe not right away, but sooner or later.

Comment: Re:828 flashing Dekatron valves (Score 1) 65

Tube logic was inefficient, and had reliability issues due to short life, but they were capable of high (MHz) switching speeds. Of course the size of things raises problems, and you have to run it a lot slower than any given gate could run, I suppose. Line driving issues, stray capacitance in the miles of wiring and whatnot, will kill your sharp edges and miss pulses.

Cold cathode, however, was slow as fuck. A couple kHz, maybe, for neon; somewhat faster for argon. Hydrogen was the fastest IIRC ( the small size must (de)ionize faster - must why they used it in high speed thyratrons for pulsed radar and whatnot also?), but still in the kHz range.

Comment: Re:Not a digital computer (Score 2) 65

However the Dekatron valves could be made in effective binary mode (9 anodes to 1 pin) so it could still be a binary computer.

That wasn't for binary, it was for allowing less complicated tubes if they were only going to be used as divide-by-10. Instead of drawing out all 10 cathodes, cathode 0 has it's own pin, and 1-9 are on a common pin... as you only need to measure / know when cathode 0 goes high again (signifying 10 pulses have occurred).

If they only needed binary it would be a flip flop instead (either tube, for 'high' speed, sometimes glow lamps in slower things)

but yeah, absolutely digital.

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