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  •  Are you an engineer? (2+ / 0-)
    Recommended by:
    JesseCW, TexasTom

    Or a professional who works with electricity or electromagnetism?

    If so, I would be interested to have the rationale for your retrospective preference for DC or AC.

    I believe the mass of professional opinion is against you.

    The hungry judges soon the sentence sign, And wretches hang, that jurymen may dine.

    by magnetics on Sun Oct 09, 2011 at 05:47:08 PM PDT

    [ Parent ]

    •  No, I'm not an engineer. (1+ / 0-)
      Recommended by:
      magnetics

      Thankfully I'm "just" a guy who's worked with and on electrically powered products.  And who likes to read a lot  :)

      We live in a DC world; from my iPhone to the current flowing through the CPU on the computer I'm typing this on.  

      AC was far superior for long distance transmission 100 years ago, one of the reasons it was adopted.  

      These days there are other solutions, one can (and many do) argue solutions that save power and materials currently used for the ever-present-need to convert the AC that runs to our houses to the DC used by all our "stuff".  

      Well, most of our stuff.  :)

      "I believe in a government which acts, which exercises its full powers and full responsibilities. Government is an art and a precious obligation..." JFK

      by Rick Aucoin on Sun Oct 09, 2011 at 05:59:07 PM PDT

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      •  Wouldn't we then need DC to DC converters (1+ / 0-)
        Recommended by:
        JesseCW

        to account for the different voltage and current needs of different appliances? Not to mention that the voltage and current needed for long-distance transmission would be much different from what appliances use. I don't see the advantage.

        "Soylent Green is a corporation!"--Mitt Romney. Eat the rich.

        by ubertar on Sun Oct 09, 2011 at 06:03:52 PM PDT

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        •  From my understanding... (0+ / 0-)

          ... simple voltage stepdowns or stepups are a far simpler process than the hoops we have to jump through every time we hook one of our many DC powered items (or DC suppliers, like solar panels) into the AC system that's delivered to our residences.

          We live in a DC world; when Westinghouse got behind AC as the standard here there were no effective DC electrical motors, but even that's no longer the case (and then some).

          Hybrid cars, all electric cars, hell, damn near everything I can think of as far as household electrical or electronic products is DC powered, other than some of the motors in the appliances around my house.  But even those could be DC, I've not gotten into my washing machine to really check.  Probably AC.  

          "I believe in a government which acts, which exercises its full powers and full responsibilities. Government is an art and a precious obligation..." JFK

          by Rick Aucoin on Sun Oct 09, 2011 at 07:18:06 PM PDT

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          •  converting AC to DC is fairly simple. (0+ / 0-)

            You just need to rectify the wave to flip the phase of the negative half of the wave. This can be done passively. Converting DC to AC is tricky, and requires additional energy.

            "Soylent Green is a corporation!"--Mitt Romney. Eat the rich.

            by ubertar on Mon Oct 10, 2011 at 05:23:08 AM PDT

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          •  I think your second paragraph is off... (0+ / 0-)

            IIRC, DC motors were around longer than AC motors. When Tesla made the first AC motor, people thought it couldn't be done... they thought the motor would keep stopping and reversing itself every 60 cycles.

            "Soylent Green is a corporation!"--Mitt Romney. Eat the rich.

            by ubertar on Mon Oct 10, 2011 at 05:25:58 AM PDT

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            •  You're quite right. (0+ / 0-)

              That's what I get for posting on so little sleep.  :)  Thanks.

              "I believe in a government which acts, which exercises its full powers and full responsibilities. Government is an art and a precious obligation..." JFK

              by Rick Aucoin on Mon Oct 10, 2011 at 01:30:02 PM PDT

              [ Parent ]

      •  For someone who works a great deal in radio (3+ / 0-)
        Recommended by:
        Rick Aucoin, JC from IA, ubertar

        I would dispute the claim that we work in a DC world.

        Signal transmission (and God knows the world uses that enough) runs exclusively in AC -- even when control lines are switched slowly, between flat levels, it is essentially AC.

        That said, I agree with you that every damn power supply I ever saw or had my hands on took AC from a socket and turned it into DC.  So no argument with you there.

        I am nonetheless highly skeptical that DC can be effectively transmitted over long distances.

        Also, for what it's worth, voltage transformation is rather more easily accomplished in AC than in DC -- particularly as it's done in AC with passive devices -- transformers.  Direct conversion between DC levels cannot obviously be done with passive components, unless you are willing to accept a lot of waste and dissipation, and even then, you only get to go downhill.  Maybe you have a counter example; if so I'd be interested.

        Curious topic, I admit.  Thanks for your response.

        The hungry judges soon the sentence sign, And wretches hang, that jurymen may dine.

        by magnetics on Sun Oct 09, 2011 at 08:47:03 PM PDT

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        •  Signal transmission, good item. (2+ / 0-)
          Recommended by:
          magnetics, ubertar

          Even with the reduction of the older television and radio in favor of more direct connect forms of data reception there's a lot of new transmission, mainly cellular.

          I must admit, that is outside of even my layman's knowledge.  

          I'll have to do a bit more reading on the voltage change issue.  I know they just avoided it, generally, way back when.  Send everything out at 110 and make the products connecting to the grid run on 100 and it worked.

          Stepping down to the more common low voltage items we use commonly... well, like I said, something for me to go read up on.  :)  Thanks.

          "I believe in a government which acts, which exercises its full powers and full responsibilities. Government is an art and a precious obligation..." JFK

          by Rick Aucoin on Sun Oct 09, 2011 at 08:52:42 PM PDT

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          •  I've been in this game a good long time (2+ / 0-)
            Recommended by:
            Rick Aucoin, ubertar

            (35 years) and find there is no end to reading, and no end to stuff I don't know about.

            The hungry judges soon the sentence sign, And wretches hang, that jurymen may dine.

            by magnetics on Sun Oct 09, 2011 at 10:24:30 PM PDT

            [ Parent ]

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