From: Duncan Frissell <frissell@panix.com>
Date: Fri, 24 Jan 1997 07:55:37 -0800 (PST)
To: Alan Bostick <abostick@netcom.com>
Subject: Re: THE NEW YORKER on the V-Chip
Message-ID: <199701241555.HAA27671@toad.com>
MIME-Version: 1.0
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At 08:23 AM 1/24/97 -0500, Alan Bostick wrote:
>Gladwell makes an analogy between V-Chipped TV content and
>air-conditioned cars in the New York City subway system in summertime:
>" . . . we need air-conditioners on subway cars because air-conditioners
>on subway cars have made stations so hot that subway cars need to be
>air-conditioned."  

Great analogy except that it's wrong.  Subway tunnels were hot before the cars ever had air conditioning.  The traditional method of controlling the amount of power delivered to an electric traction motor was to run the juice through a resistor array.  As the motorman moved the controller up and down, the current would pass through fewer and more banks on the grid of resistors and the amount delivered to the motors would change.  Well you might guess that at 600 V DC and I don't know how many Watts, those resistor grids had to dump a lot of heat.  They were/are located on the tops or bottoms of cars and are quite apparent when the cars pass you on a winter morning.

DCF
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