On Sat, 26 Jun 2004, Major Variola (ret) wrote:
I'm fully aware the pigs track you unless the battery is removed or you have a TEMPEST case. I'm suggesting that regular citizens will have access to that, if (in my cluelessness) they don't already.
If the phone is shielded, it can't transmit/receive, which makes it rather useless. :( There is one potential landmine as well; the inherent ability of any device containing resonators to behave like a crude RFID tag. I heard somewhere, and my memory may be failing, that it is possible to irradiate the phone with the frequency of the cellular band, and it faintly resonates and returns back its own echo, which has minute variations given by type, manufacturing tolerances, and possibly age of the phone, giving it a kind of unique signature. (This could potentially apply also to radios and transceivers. Does anybody have any idea if it is possible to do such kind of "active fingerprinting" of rf devices? This way it should be possible to detect even powered-off devices like hidden transceivers or body wires; take a transmitter, sweep the spectrum, and watch echoes on the receiver - there could be peaks on the frequencies of the tuned circuits inside the examined device.) Question to RF heads here: could it work?