The FIREWALL CHIP. U're phone always offhook?
Robert Rothenburg Walking-Owl
rrothenb at ic.sunysb.edu
Fri Feb 3 14:00:10 PST 1995
>From a couple of folx....
> > Actually, there is a germ of truth in this. On older phones (don't know if
> > this works on newer electronic phones) when the handset is 'on-hook' a
> > switch opens and breaks the voice circuit. This of course only works for
> > DC circuits. If you drive that same circuit with an AC signal . . .
>
> There's another angle I may have mentioned before. Many
> electronic phones come with a ``feature'' that allows you to
> call home, produce an electronic tone and eavesdrop on your own
> house. When the tone is sounded, the ringing stops (or never
> starts) and the phone goes into ``off hook'' mode (i.e., the
> microphone in the mouthpiece is turned on).
>
[ Snip! ]
A simpler solution is to keep the phone in another room used mainly for
phonecalls, or even in a small office if you don't make an sounds there
worth evesdropping on. (The really paranoid can soundproof/tempest-proof
the room....)
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