- Tue Sep 05, 2006 7:09 am
#18386
for CDMA/TDMA it's mostly useless and that's why you get those things telling you you were in another city while making a call sometimes on your bill, I had one of those with GSM once, my phone company was very confused, ended up it was a really bad calculation in their system, kinda caught them with their pants down.
The clipper chip didn't officially make it into phones, you're right. But it doesn't have to be in the phone, the phone has to send a single analog signal for audio in theory, but your phone doesn't, it sends several digitally encoded analog channels for audio, and one of those channels passes through a clipper system in the US, which listens for keywords and phrases, if it catches enough words to reach a priority # it starts recorded, as the number raises flags are set which may bring the recording to the attention of 'someone', if not enough points are accrued in the given time from the first priority word it's reset. Very simple, and works with basic voice recognition techniques when filtered properly. not a perfect system and not something that can be used in court because it violates your right to privacy, but it is there. It's also used on most new telephone land lines too.
Officially there's no clipper chip in a cell phone, but the audio encoder gives off an excess digital signal which is not used during a call. Maybe it's a conspiracy theory either way, I don't like the idea.
Back to the actual topic, there are ways to import it but you'd have to be a company working in the proper field, and do a lot of paperwork and not be selling it...best of luck!
maokh wrote:Customs will always be hit and miss. Thats why you get it insured. I need an actual, steady, legitimate supply of the newer GM86x series modules...so sneaking them into the states really doesnt sound interesting to me.You're right triangulation is difficult, in fact on the broad scale nearly impossible, however generalized location information is simple with a cellular system, in fact just like the name implies a cellular network is divided into cells or grids in areas between towers, and they can tell what general area you're in, otherwise they couldn't charge you for roaming. And nowadays with the more advanced GSM and GPRS services it's frightening how much locational information a phone can give, if you don't believe me, go hack your GPRS enabled phone, you'll see what I mean if you look closely and are able to process the right information in a way similar to how the network does. I've worked for 4 cell phone companies
Are you talking about the clipper chip?! That never actually made it into production, the project was defunct in 1996. LBS also was not intergated until well after 2000. Before, triangulation was very difficult. Anyone who has ever had to do any law enforcement triangulation with AMPS/TDMA systems would know what i mean. Even GSM systems...
The GPS LBS systems also suck. When GPS signal is degrated or unavailable (more often than not), location data is extremely skewed. An LBS event on my CDMA E911/AGPS phones tell me i am 20 miles away from my home. Yikes.
for CDMA/TDMA it's mostly useless and that's why you get those things telling you you were in another city while making a call sometimes on your bill, I had one of those with GSM once, my phone company was very confused, ended up it was a really bad calculation in their system, kinda caught them with their pants down.
The clipper chip didn't officially make it into phones, you're right. But it doesn't have to be in the phone, the phone has to send a single analog signal for audio in theory, but your phone doesn't, it sends several digitally encoded analog channels for audio, and one of those channels passes through a clipper system in the US, which listens for keywords and phrases, if it catches enough words to reach a priority # it starts recorded, as the number raises flags are set which may bring the recording to the attention of 'someone', if not enough points are accrued in the given time from the first priority word it's reset. Very simple, and works with basic voice recognition techniques when filtered properly. not a perfect system and not something that can be used in court because it violates your right to privacy, but it is there. It's also used on most new telephone land lines too.
Officially there's no clipper chip in a cell phone, but the audio encoder gives off an excess digital signal which is not used during a call. Maybe it's a conspiracy theory either way, I don't like the idea.
Back to the actual topic, there are ways to import it but you'd have to be a company working in the proper field, and do a lot of paperwork and not be selling it...best of luck!