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World Tesla Day

Posted 2012.07.10 8.00 in Computers/Internet/Technology by Stephanie

July 10th is Nicola Tesla’s birthday. Tesla was under-appreciated during his lifetime, and for a long time after he died. Lately he’s getting more press, which is good, but late.

Nikola Tesla (1856 – 1943)

You can read some factual stuff about Tesla here, and some fun and factual stuff about Tesla here.

One thing about Tesla that stood out to me in his biography, was that he invented the alternating-current electric motor. That is, a motor which spins around and around in one direction, while powered by A/C electricity, which moves back and forth in both directions. According to his biography, he invented it after overhearing a couple university professors saying that such a thing was simply impossible and could not be done.

Incase you don’t realize how big this is, here’s a very short list of things you plug into an electrical outlet, that exist because Tesla invented his motor: Air Conditioner; Washing Machine; Dryer; Dishwasher; Blender; Food Processor; Electric Pumps; Vacuum Cleaner; Sewing Machine; Power Tools (drills, saws, milling machines, lathes, routers); Elevators; Escalators.

So in other words, basically every modern convenience in our homes and factories, exists thanks to Tesla setting out to proove a couple university professors wrong.

Not only did he invent the A/C electric motor, but from what I have read, Tesla didn’t actually make any money from this invention – he gave it away, because he thought it would benefit mankind.

So next time you turn up the air conditioner, blow-dry  your hair, or mix up a daquiry in the blender, stop a moment and think about the man who made it possible. Despite his brilliance and all his gifts to the modern world, he died broke and alone, unappreciated in his own time.

Thank you Mr. Tesla. Thank you for everything.

I’ll make some sparks and raise a glass.

Why they call it a Hot Shoe

Posted 2009.08.13 10.18 in Photography, Pointless Blather by Stephanie

I never really thought about it before – but the bit where a flash attaches to the top of a camera? They call that the Hot Shoe. It’s one of those things that you just sort of accept. Like apertures and diopters and f-stops – they’re just words and you learn the words and that’s that.

Camera's Hot Shoe

The Hot Shoe

But in fact there’s a reason that they call it a “hot shoe” – as opposed to just “shoe”, for example.

I discovered this while playing with an external flash. The bottom (“foot”) of the flash has little metal contacts that connect to the contacts on the camera’s hot shoe. When you push the shutter release, a connection is made internally that tells the flash to fire. So far, so good.

What makes it “hot” is that on some / many flashes, the entire electrical charge goes through there! Honestly, I never would have guessed that. I just figured there’d be a small, low-voltage signal that triggered the flash to fire. Nope! When the flash is charged, there could be 250 volts or more, waiting around the big pin in the foot of the flash.

Remember when I said I was playing with a flash? The flash had been charged up but then I opened it and took the batteries out. And at one point, the way I was holding it, my hand happened to be touching the “foot” when a finger brushed against one of the battery contacts (the ground contact of course).


It bit me! Before that moment, I simply never would have imagined that a flash would run the full charge down and out the foot, into the camera, then back up into the flash.

That’s why they call it a “hot shoe”!

Flash Foot

WTF is with these Utility Cons?

Posted 2009.07.23 11.05 in Pointless Blather, Work by Stephanie

We’ve all encountered situations like this. Someone shows up at your door, at home or at work, with an official-looking clipboard, an official-looking photo-id badge, and a rehearsed spiel that they are here from an official-sounding company, on behalf of a legitimate company or utility, and they are going to save you some money.

As you know, long distance has been deregulated, and now you can save a lot of money by signing this contract so that your long distance is covered by this new low-cost business. Maybe you’ve heard that natural gas prices are going up and up, and they can save you hundreds of dollars over the next 5 years if you sign a contract to pay a fixed rate? Perhaps you’ve heard that the price of electricity is on the rise, and they can save you a lot of money if you’ll sign a contract to pay a fixed rate over the next few years? And the latest one: We can save you a lot of money over the next few years, because you know the United Nations is pushing to have every country start charging a carbon tax, and if you just sign this contract we can take care of that for you…

No, I’m not talking about the poor shlep who’s been walking around for 8 hours a day – he’s already been victimized, and sadly he probably even believes the bullshit that he’s telling you. I’ll explain momentarily.

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