NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Cell phone time, dip at beach!
From: Jared Sherman
Date: 2005 Apr 10, 13:51 -0400
From: Jared Sherman
Date: 2005 Apr 10, 13:51 -0400
Mike-A US-centric answer: If you are using a CDMA cell phone, the exact time is required in order for the CDMA system to do the internal work of chopping the calls up and reassembling them at the cell tower. So, that system broadcasts time to all the phones, which are simply showing "system time" that comes from various sources like GPS receivers at the towers. IOW, you're getting GPS time or something similar. Users of TDMA and analog phones do *not* get anything similar. With a GSM or GSM/GPRS phone, I'm not sure what you get because there are different implementations. But I think most of them also are displaying "system time" even though some of the new phones have built-in clocks and alarms to use when they are off the system.
