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From: larry@kitty.UUCP (Larry Lippman)
Newsgroups: sci.electronics
Subject: Re: Phone Harassment
Summary: More nonsense...
Message-ID: <3669@kitty.UUCP>
Date: 18 Mar 90 16:28:52 GMT
References: <21849@watdragon.waterloo.edu> <13746@watcgl.waterloo.edu> <1990Mar17.145353.2911@ddsw1.MCS.COM>
Distribution: na
Organization: Recognition Research Corp., Clarence, NY
Lines: 31

In article <1990Mar17.145353.2911@ddsw1.MCS.COM>, benfeen@ddsw1.MCS.COM (Ben Feen) writes:
> >>I saw an interesting method of getting back at phone harrassers - It
> >>involves a car battery, a large capacitor, and some wiring thru your phone.
> >
> >Ben, you have a lot to learn about Fiber Optics.
> >
> Yes, I know... This was an old old old trick - Before the ESS and fiber
> optics.  Besides, it was actually for modems - They often aren't surge
> protected, and it wouldn't take much of a jolt.

	It was a trick alright - because such a method could never damage
modems or anything else, for that matter.

	Even in an older SxS CO with a metallic path between each subscriber
line and the SxS "connector", the calling and called parties were connected
using two 2 uF capacitors - allowing no direct DC path.  Furthermore, both
calling and called parties were connected to ground and -48 V CO battery
using 200 ohm windings on their respective supervisory relays, with such
metallic connection providing a substantial "clamp" for any attempt to
impose excessive voltages across a subscriber line.

	Also, I have news for you - there is >>MUCH<< more electrical energy
available across a subscriber telephone line during normal CO ringing 
than could be intentially transmitted through any other means.  Surge
protectors are intended to clamp voltages FAR in excess of normal CO
ringing.

<> Larry Lippman @ Recognition Research Corp. - Uniquex Corp. - Viatran Corp.
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