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A Story About ‘Magic' (1994)

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Re: A Story About ‘Magic' (1994)

#51

Post by andars »

snissn wrote: post #49
semi-extrinsic wrote: post #25

Earlier quoted context omitted.

A friend of mine, working on his PhD in a European university which shall not be named, is using a really old 15 watt ruby laser for some experiments. One day last year it would not turn on, and he and his labmates spent hours trying to diagnose the problem. Finally one of them, exasperated, put his elbow on top of the laser cabinet with a deep sigh, whereupon the laser promptly started working. Excited, they found a…

Out of curiosity, why does someone studying European history need a 15 watt laser?

European universities teach things other than European history.

Re: A Story About ‘Magic' (1994)

#52

Post by tlear »

beachstartup wrote: post #20
sthreet wrote: post #18

Earlier quoted context omitted.

What does "trust the map over the terrain" mean?

when the map tells you one thing, and your eyes tell you another thing, go with what your eyes tell you, because the map is full of shit. you would be surprised how often people trust "the map" more than reality. "the map" can be anything, i.e. an instruction manual, an authority figure, folklore, a rumor, whatever.

My dad's friend destroyed film he took of his wedding like that. He developed it himself, water felt hot to his finger but thermometer showed it right. He cooked it.. thermometer was broken. His wife was not amused!

Re: A Story About ‘Magic' (1994)

#54

Post by freyr »

parfe wrote: post #50
mcphage wrote: post #34

Earlier quoted context omitted.

Is it common for one of the switch terminals to be electrically connected to the switch's container? That seems like a dangerous idea?

Common? Hell no! Obvious? Yes. For a switch to work a circuit must be present. Either a neutral line or a ground it is the only way to send information. If a functioning switch has only a single wire feeding into it then it must be reaching ground through other means.

> If a functioning switch has only a single wire feeding into it then it must be reaching ground

False dichotomy. You omitted a third option: magic.

Re: A Story About ‘Magic' (1994)

#56

Post by ProAm »

agumonkey wrote: post #44
semi-extrinsic wrote: post #25

Earlier quoted context omitted.

A friend of mine, working on his PhD in a European university which shall not be named, is using a really old 15 watt ruby laser for some experiments. One day last year it would not turn on, and he and his labmates spent hours trying to diagnose the problem. Finally one of them, exasperated, put his elbow on top of the laser cabinet with a deep sigh, whereupon the laser promptly started working. Excited, they found a…

Pragmatic but sad, I expected some nice collective eureka moment after a mental struggle.

Don't look a gift horse in the mouth. (and never invest money in something that eats while you sleep)

Re: A Story About ‘Magic' (1994)

#57

Post by kbart »

parfe wrote: post #30
peterwwillis wrote: post #9

Uh... How was this not obvious from looking at it? Every geek who's put together or taken apart a computer knows the metal frame is grounded, and most geeks have enough basic understanding of electricity to understand you only need one wire for a ground. The switch enables or disables grounding. Since that is literally the only thing it can do, that is what it does.

Haha HN, how did this post get downvotes? The second I read about "a switch needing two wires" I thought "Unless it's grounded." Interesting story, but hardly "magic"

I suspected ground potential differences halfway through the article too, but I guess for web "hackers" out there it's equal to magic.

Re: A Story About ‘Magic' (1994)

#58

Post by robin_reala »

infamousblah wrote: post #47
jimminy wrote: post #33

Earlier quoted context omitted.

The original Playstation had a similar switch on the lid mechanism. I think it was a safety feature to prevent the discs from spinning up, without the enclosure. When I was about 8-9, I found the mechanism, and ended up dismantling the system. I then wedged a little Wolverine action-figure's foot into the space to keep his foot down on the switch and ran the system without the cover, because it looked pretty badass t…

This could also be used to run out-of-region discs on the US market version of the Playstation. It refused to start with a out-of-region disc, but you could start with a US disc and then swap in the out-of-region disc while running, provided it never detected the lid opening.

I had a little spring for mine that clipped over the prong in the lid at one end, and pressed the switch down at the other. You could still open/close the lid, but the Playstation wouldn’t recognise it.

Re: A Story About ‘Magic' (1994)

#59

Post by loopbit »

Intermernet wrote: post #45
beachstartup wrote: post #20

Earlier quoted context omitted.

when the map tells you one thing, and your eyes tell you another thing, go with what your eyes tell you, because the map is full of shit. you would be surprised how often people trust "the map" more than reality. "the map" can be anything, i.e. an instruction manual, an authority figure, folklore, a rumor, whatever.

Except if you're a pilot flying in low visibility. Then you trust the map, not the terrain (mainly as the terrain is invisible). VFR vs. IFR and all that.

SO your point is that you trust the map only when there's no other option.

Re: A Story About ‘Magic' (1994)

#60

Post by T-hawk »

jimminy wrote: post #33
devindotcom wrote: post #8

I love things like this. In my old Dreamcast, I found after I'd packed it up and moved it a few too many times that it wouldn't start, but would show signs of life when the lid would open and close. I found that there was a position you could put the lid in at which it would boot, and that position could be reliably reached if a SweeTart was placed in the tray near the edge of the disc. I licked the flat side of the…

The original Playstation had a similar switch on the lid mechanism. I think it was a safety feature to prevent the discs from spinning up, without the enclosure. When I was about 8-9, I found the mechanism, and ended up dismantling the system. I then wedged a little Wolverine action-figure's foot into the space to keep his foot down on the switch and ran the system without the cover, because it looked pretty badass t…

You were fine. The Playstation 1's CD drive spins at only 2x regular audio speed which is no more than 16 Hz rotational speed. It's nothing like the 48x fighter jet turbines of desktop computers. It's only 2x as much as a handheld Discman that has no safety interlocks at all.

All consoles from the PS2 onwards have an enclosed (tray or slot) drive mechanism because they do spin the disc fast enough for safety to be an issue, but the early disc media systems up to the Dreamcast didn't need to worry about it.

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