At 08:08 PM 9/16/2003 -0500, you wrote:
>>Does anyone have any idea how much power you could tap from
>>the line without causing it to go off hook?

>very little.
>
>this page will help you a lot.
>http://www.ce-mag.com/99ARG/Gubish233.html

There was a book published, I think, by DEC, on telecom theory.  In it was
explained the development of the modern (in the US since way back... around
1900??? someone correct the date if you know it) phone system using
automated connection equipment.

Paraphrasing from my poor memory, the story went like this.  In the United
States midwest area - Missouri? - there was a small town with two
undertakers.  One of them always seemed to get more business than the
other.  The smaller one was owned by a person named Strowger.  Strowger
looked into the situation and found that the wife of the other undertaker
happened to be the town telephone operator.  When someone would call the
operator and ask for the undertaker, she would invariably put the call
through to her husbands business.  Strowger thought about this and realized
that his business was being cut short due to this method.

Strowger thought a little bit further and realized that the phone was here
to stay and that the ramifications were plentiful.  He decided to put the
"operator" out of business.  He came up with a design for an automated
dialing system with a motor-relay-switch gizmo that would automatically
connect you to the phone number you wanted and the operator would not be
needed.  He patented his design successfully.  The rest is history.  Of
course, someone else would have done it if he had not but he *is* the one
who did it.  Ok, I'll stop now.

Tom

ps the company I worked for when I read this book (to learn about modems
and such) made flowmeters that were used in sewers to measure wastewater
flow rates.  They put a modem in one and connected phone lines to it and
could then get the data out of it by dialing it directly.  One problem
remained - how to deal with batteries that run down.  They got the 'bright'
idea to call it all night long and have it not answer, thereby using the
100+ volt ring signal to charge the batteries.  The charge circuit had to
take no more power than the usual telephone ringer of the time.  It's all
history now from over 20 years ago but fun to look back on.

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