🚀 go-pugleaf

In article <45.260081ad@spcvxa.spc.edu> terry@spcvxa.spc.edu (Terry Kennedy) writes:
>In article <1990Mar16.001210.27602@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.
>> I'm not gonna go into it, but if you go through a certain sequence, you can
>> send a surge through Ma Bell's wires, straight into the offender's
>> handset..........
>
>  Uh-huh. Right. First, if you indeed send a high-current "surge through Ma
>Bell's wires" the first and _only_ thing you're going to take out are the
>fuses for _your_ phone line. Even supposing you got past that, _and_ that
>it was a local call _and_ it was on a mechanical switch (which is getting
>less and less likely), the phone on the far end is transformer-coupled, so 
>all they would hear is a brief "click". Since any calls outside the local
>mechanical switch are transformer- or electonically- converted to 4-wire,
>it wouldn't get out of your local switch. Likewise, when you feed the A/D
>converter in an electronic switch, it won't see it either.
>
>  By the way, current local loop cable is something like #24 or #26 cable
>(down from #18 tin-over-copper in the old cotton-wrapped pressurized lead-
>jacketed cables). You can't put a lot of current through #26. If you did,
>you'd melt the cable (that's why they have the fuses at their end). If you
>did melt the cable, you'd have some _very_ irate telephone security folks
>visiting you - or at least you would have when I was working for the phone
>company...
>
>	Terry Kennedy		Operations Manager, Academic Computing
>	terry@spcvxa.bitnet	St. Peter's College, US
>	terry@spcvxa.spc.edu	(201) 915-9381

There is one more interesting fact, which I have not yet seen mention
of here: Telephone handsets are made of PLASTIC. You could probably
put a good solid thousand volts on the stupid thing, and the person
talking into it would never be the wiser, unless they stuck their
tongue through the itty bitty holes. Fat chance!

Even if you _could_ put a high-voltage pulse through it (doesn't
matter how small the wires are - remember, if the pulse is short, you
aren't going to push enough coulombs down the wire to blow any fuses),
and even if the phone _weren't_ transformer-coupled, the worst you
could do is offend the person's ear with a fairly obnoxious "BANG!"
sound.

I suspect that this technique might have worked...about a hundred
years ago. I think that the handsets were still metal then, and the
switching was all definitely capable of handling DC.

Cheers from Your Little Electronic Friend (or is that Fiend?),
jon singer (Former Hardware Hack, current technical writer. When I'm
not at work or in bed, sometimes I design and build pulsed lasers. I
typically operate them at 20,000 volts or so. I have at least _some_
understanding of this issue.)

-- 
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	When I think back on all the		|
	crap I learned in highschool /		|	Jon Singer
	It's a wonder I can think at all!	|	is jon@Apple.COM, or
	   - Paul Simon, Kodachrome		|	(AppleLink) SINGER2
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