Telephone handset can be used for calls via mobile cell network or as cordless phone for use with nearby landline connection point

摘要

The handset (1) is identical in appearance to a conventional GSM mobile phone, except that it has an additional button (32). Inside the handset are additional integrated circuits (8, 12, 28) which provide the facility to use the handset in three ways: (A) only as a conventional mobile phone, (B) only as a conventional cordless phone or (C) either mobile or cordless.