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Old 11th Mar 2014, 14:51
  #1798 (permalink)  
The Ancient Geek
 
Join Date: May 2010
Location: UK
Age: 79
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Mobile phones ringing

Please can we put this recurrent theory to bed.

Short version - the ringing tone returned to the caller is bogus.

Why it happens -
Cellular phone systems first try to route a call to the last cell which was in contact with the phone. If this fails the system tries to locate the phone to other cells and then tries to divert to voicemail.
All of this searching takes time, during which a caller hearing silence would probably hang up before the call can be connected so the system returns a ringing tone to the caller. In most cases this is a successful strategy but it does mean that if the phone is not eventually found the caller is misled into believing that it is working OK but not being answered.
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