

NSA growth fueled by need to target terrorists - raganwald
http://www.washingtonpost.com/world/national-security/nsa-growth-fueled-by-need-to-target-terrorists/2013/07/21/24c93cf4-f0b1-11e2-bed3-b9b6fe264871_print.html

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raganwald
I'm curious: How do they detect the location of a cell phone that is turned
off?

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happypatrik
"Some handsets can't be fully powered down without removing the battery; for
instance, some Nokia models will wake up when turned off if an alarm is set."
([http://news.cnet.com/2100-1029-6140191.html](http://news.cnet.com/2100-1029-6140191.html))
I'm guessing that there even might be models with built in battery backup for
this kind of functionality.

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cinquemb
And with that: Cellular devices are designed to transmit some kind of pilot
signal even when turned off but with operational battery

[http://www.endoacustica.com/gsm_interceptor_en.htm](http://www.endoacustica.com/gsm_interceptor_en.htm)

