Finding service provider switching ON This topic has 0 replies, 1 voice, and was last updated 11 years, 6 months ago by Dan. Viewing 1 post (of 1 total) Author Posts 21st July 2013 at 08:45 #69160 DanGuest Hi Experts How do a mobile recognize the correct optr(amidst a lot of them),are the ferquencies stored in SIM?Pls explain Thanks Dan Author Posts Viewing 1 post (of 1 total) The forum ‘Telecom Design’ is closed to new topics and replies.